Datasheet LM1575, LM2575-N, LM2575HV Specification

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LM1575/LM2575/LM2575HV SIMPLE SWITCHER®1A Step-Down Voltage Regulator
Check for Samples: LM1575, LM2575-N, LM2575HV
1
23
3.3V, 5V, 12V, 15V, and Adjustable Output Versions
Adjustable Version Output Voltage Range, – 1.23V to 37V (57V for HV Version) ±4%
Max Over
Line and Load Conditions
Specified 1A Output Current
Wide Input Voltage Range, 40V up to 60V for HV Version
Requires Only 4 External Components
52 kHz Fixed Frequency Internal Oscillator
TTL Shutdown Capability, Low Power Standby Mode heat sink, and in many cases no heat sink is
High Efficiency
Uses Readily Available Standard Inductors
Thermal Shutdown and Current Limit Protection
P+Product Enhancement Tested

APPLICATIONS

Simple High-Efficiency Step-Down (Buck) Regulator
Efficient Pre-Regulator for Linear Regulators
On-Card Switching Regulators
Positive to Negative Converter (Buck-Boost)

DESCRIPTION

The LM2575 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 1A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V, and an adjustable output version.
Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed­frequency oscillator.
The LM2575 series offers a high-efficiency replacement for popular three-terminal linear regulators. It substantially reduces the size of the
required. A standard series of inductors optimized for use with
the LM2575 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies.
Other features include a specified ±4% tolerance on output voltage within specified input voltages and output load conditions, and ±10% on the oscillator frequency. External shutdown is included, featuring 50 μA (typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions.

Typical Application

(Fixed Output Voltage Versions)
Pin numbers are for the TO-220 package.
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2SIMPLE SWITCHER is a registered trademark of Texas Instruments. 3All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
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Block Diagram and Typical Application

3.3V, R2 = 1.7k 5V, R2 = 3.1k 12V, R2 = 8.84k 15V, R2 = 11.3k For ADJ. Version R1 = Open, R2 = 0Ω Pin numbers are for the TO-220 package.
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Figure 1.
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Connection Diagrams

(XX indicates output voltage option.)
Top View Top View Side View
Figure 2. Straight Leads Figure 3. Bent, Staggered Leads Figure 4. LM2575T-XX Flow LB03
5-Lead TO-220 Package 5-Lead TO-220 Package LM2575T-XX or LM2575HVT-XX See Package Number NDH0005D See Package Number KC0005A
Top View Top View
LM2575HVT-XX Flow LB03
See Package Number NDH0005D
or
*No Internal Connection
*No Internal Connection
Figure 5. 16-Lead CDIP and PDIP Packages Figure 6. 24-Lead Surface Mount SOIC Package
LM2575N-XX or LM2575HVN-XX LM2575M-XX or LM2575HVM-XX
LM1575J-XX-QML See Package Number DW0024B
See Package Numbers NFE0016A and NBG
Top View
Figure 7. DDPAK/TO-263 Package
5-Lead Surface-Mount Package
See Package Number KTT0005B
Side View
Figure 8. LM2575S-XX or LM2575HVS-XX
See Package Number KTT0005B
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These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.

ABSOLUTE MAXIMUM RATINGS

(1)(2)(3)
Maximum Supply Voltage LM1575/LM2575 45V
LM2575HV 63V ON /OFF Pin Input Voltage 0.3V V +V Output Voltage to Ground (Steady State) 1V Power Dissipation Internally Limited Storage Temperature Range 65°C to +150°C Maximum Junction Temperature 150°C Minimum ESD Rating (C = 100 pF, R = 1.5 kΩ) 2 kV Lead Temperature (Soldering, 10 sec.) 260°C
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but do not ensure specific performance limits. For specified specifications and test
conditions, see Electrical Characteristics. (2) If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications. (3) Refer to RETS LM1575J for current revision of military RETS/SMD.

OPERATING RATINGS

Temperature Range LM1575 55°C TJ≤ +150°C
LM2575/LM2575HV 40°C TJ≤ +125°C
Supply Voltage LM1575/LM2575 40V
LM2575HV 60V
IN

ELECTRICAL CHARACTERISTICS LM1575-3.3, LM2575-3.3, LM2575HV-3.3

Specifications with standard type face are for TJ= 25°C, and those with boldface type apply over full Operating Temperature Range .
Symbol Parameter Conditions Typ
SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26
V
OUT
Output Voltage VIN= 12V, I
Circuit Figure 25 and Figure 26
LOAD
(3)
= 0.2A 3.3 V
LM1575-3.3
(1)
Limit
3.267 3.234 V(Min)
3.333 3.366 V(Max)
V
OUT
Output Voltage 4.75V VIN≤ 40V, 0.2A ≤ I LM1575/LM2575 Circuit Figure 25 and Figure 26
LOAD
1A 3.3 V
3.200/3.168 3.168/3.135 V(Min)
3.400/3.432 3.432/3.465 V(Max)
V
OUT
Output Voltage 4.75V VIN≤ 60V, 0.2A ≤ I LM2575HV Circuit Figure 25 and Figure 26
LOAD
1A 3.3 V
3.200/3.168 3.168/3.135 V(Min)
3.416/3.450 3.450/3.482 V(Max)
η Efficiency VIN= 12V, I
= 1A 75 %
LOAD
(1) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to
calculate Average Outgoing Quality Level, and all are 100% production tested. (2) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. (3) External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance.
When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system
parameters of Electrical Characteristics.
LM2575-3.3
LM2575HV-3.3
(2)
Limit
Units
(Limits)
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ELECTRICAL CHARACTERISTICS LM1575-5.0, LM2575-5.0, LM2575HV-5.0

Specifications with standard type face are for TJ= 25°C, and those with boldface type apply over full Operating Temperature Range.
Symbol Parameter Conditions Typ
SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26
V
OUT
Output Voltage VIN= 12V, I
Circuit Figure 25 and Figure 26
LOAD
(3)
= 0.2A 5.0 V
LM1575-5.0
(1)
Limit
4.950 4.900 V(Min)
5.050 5.100 V(Max)
V
OUT
Output Voltage 0.2A I LM1575/LM2575 8V VIN≤ 40V
LOAD
Circuit Figure 25 and Figure 26
1A, 5.0 V
4.850/4.800 4.800/4.750 V(Min)
5.150/5.200 5.200/5.250 V(Max)
V
OUT
Output Voltage 0.2A I LM2575HV 8V VIN≤ 60V
LOAD
Circuit Figure 25 and Figure 26
1A, 5.0 V
4.850/4.800 4.800/4.750 V(Min)
5.175/5.225 5.225/5.275 V(Max)
η Efficiency VIN= 12V, I
= 1A 77 %
LOAD
(1) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to
calculate Average Outgoing Quality Level, and all are 100% production tested. (2) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. (3) External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance.
When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system
parameters of Electrical Characteristics.
LM2575-5.0
LM2575HV-5.0
(2)
Limit
Units
(Limits)

ELECTRICAL CHARACTERISTICS LM1575-12, LM2575-12, LM2575HV-12

Specifications with standard type face are for TJ= 25°C, and those with boldface type apply over full Operating Temperature Range .
Symbol Parameter Conditions Typ
SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26
V
OUT
Output Voltage VIN= 25V, I
Circuit Figure 25 and Figure 26
LOAD
(3)
= 0.2A 12 V
LM1575-12
(1)
Limit
11.88 11.76 V(Min)
12.12 12.24 V(Max)
V
OUT
Output Voltage 0.2A I LM1575/LM2575 15V VIN≤ 40V
1A, 12 V
LOAD
Circuit Figure 25 and Figure 26
11.64/11.52 11.52/11.40 V(Min)
12.36/12.48 12.48/12.60 V(Max)
V
OUT
Output Voltage 0.2A I LM2575HV 15V VIN≤ 60V
1A, 12 V
LOAD
Circuit Figure 25 and Figure 26
11.64/11.52 11.52/11.40 V(Min)
12.42/12.54 12.54/12.66 V(Max)
η Efficiency VIN= 15V, I
= 1A 88 %
LOAD
(1) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to
calculate Average Outgoing Quality Level, and all are 100% production tested. (2) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. (3) External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance.
When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system
parameters of Electrical Characteristics.
LM2575-12
LM2575HV-12
(2)
Limit
Units
(Limits)
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ELECTRICAL CHARACTERISTICS LM1575-15, LM2575-15, LM2575HV-15

Specifications with standard type face are for TJ= 25°C, and those with boldface type apply over full Operating Temperature Range .
Parameter Conditions Typ
Symbol Limit
SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26
V
OUT
Output Voltage VIN= 30V, I
Circuit Figure 25 and Figure 26
LOAD
(3)
= 0.2A 15 V
LM1575-15
(1)
14.85 14.70 V(Min)
15.15 15.30 V(Max)
V
OUT
Output Voltage 0.2A I LM1575/LM2575 18V VIN≤ 40V
1A, 15 V
LOAD
Circuit Figure 25 and Figure 26
14.55/14.40 14.40/14.25 V(Min)
15.45/15.60 15.60/15.75 V(Max)
V
OUT
Output Voltage 0.2A I LM2575HV 18V VIN≤ 60V
1A, 15 V
LOAD
Circuit Figure 25 and Figure 26
14.55/14.40 14.40/14.25 V(Min)
15.525/15.675 15.68/15.83 V(Max)
η Efficiency VIN= 18V, I
= 1A 88 %
LOAD
(1) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to
calculate Average Outgoing Quality Level, and all are 100% production tested. (2) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. (3) External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance.
When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system
parameters of Electrical Characteristics.
LM2575-15
LM2575HV-15
(2)
Limit
Units
(Limits)

ELECTRICAL CHARACTERISTICS LM1575-ADJ, LM2575-ADJ, LM2575HV-ADJ

Specifications with standard type face are for TJ= 25°C, and those with boldface type apply over full Operating Temperature Range.
Symbol Parameter Conditions Typ
SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26
V
OUT
Feedback Voltage VIN= 12V, I
V
= 5V
OUT
Circuit Figure 25 and Figure 26
LOAD
(3)
= 0.2A 1.230 V
LM1575-ADJ
(1)
Limit
1.217 1.217 V(Min)
1.243 1.243 V(Max)
V
OUT
V
OUT
η Efficiency VIN= 12V, I
Feedback Voltage 0.2A I LM1575/LM2575 8V VIN≤ 40V
Feedback Voltage 0.2A I LM2575HV 8V VIN≤ 60V
LOAD
V
= 5V, Circuit Figure 25 and
OUT
Figure 26 1.255/1.267 1.267/1.280 V(Max)
LOAD
V
= 5V, Circuit Figure 25 and
OUT
Figure 26 1.261/1.273 1.273/1.286 V(Max)
LOAD
1A, 1.230 V
1.205/1.193 1.193/1.180 V(Min)
1A, 1.230 V
1.205/1.193 1.193/1.180 V(Min)
= 1A, V
= 5V 77 %
OUT
(1) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to
calculate Average Outgoing Quality Level, and all are 100% production tested. (2) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. (3) External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance.
When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system
parameters of Electrical Characteristics.
LM2575-ADJ
LM2575HV-ADJ
(2)
Limit
Units
(Limits)
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ELECTRICAL CHARACTERISTICS ALL OUTPUT VOLTAGE VERSIONS

Specifications with standard type face are for TJ= 25°C, and those with boldface type apply over full Operating Temperature Range. Unless otherwise specified, VIN= 12V for the 3.3V, 5V, and Adjustable version, VIN= 25V for the 12V
version, and VIN= 30V for the 15V version. I
Symbol Parameter Conditions Typ
DEVICE PARAMETERS
I
b
f
O
V
SAT
DC Max Duty Cycle (ON) See
I
CL
I
L
I
Q
I
STBY
θ
JA
θ
JA
θ
JC
θ
JA
θ
JA
θ
JA
Feedback Bias Current V Oscillator Frequency See
Saturation Voltage I
= 5V (Adjustable Version Only) 50 100/500 100/500 nA
OUT
(3)
= 1A
OUT
(5)
Current Limit Peak Current
Output Leakage Output = 0V 2 2 mA(Max) Current Output = 1V
Output = 1V
Quiescent Current See
(6)
Standby Quiescent ON /OFF Pin = 5V (OFF) 50 μA Current
Thermal Resistance TO-220 Package, Junction to Ambient
TO-220 Package, Junction to Ambient TO-220 Package, Junction to Case 2 CDIP Package, Junction to Ambient SOIC Package, Junction to Ambient DDPAK/TO-263 Package, Junction to Ambient 37
(11)
LOAD
(4)
(4)(3)
= 200 mA.
(6)(7)
(10) (10)
LM1575-XX
(1)
Limit
LM2575-XX
LM2575HV-XX
(2)
Limit
Units
(Limits)
52 kHz
47/43 47/42 kHz(Min) 58/62 58/63 kHz(Max)
0.9 V
1.2/1.4 1.2/1.4 V(Max)
98 %
93 93 %(Min)
2.2 A
1.7/1.3 1.7/1.3 A(Min)
3.0/3.2 3.0/3.2 A(Max)
7.5 mA 30 30 mA(Max)
5 mA
10/12 10 mA(Max)
200/500 200 μA(Max)
(8) (9)
65 45
85 °C/W
100
(1) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to
calculate Average Outgoing Quality Level, and all are 100% production tested.
(2) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control (SQC) methods.
(3) The oscillator frequency reduces to approximately 18 kHz in the event of an output short or an overload which causes the regulated
output voltage to drop approximately 40% from the nominal output voltage. This self protection feature lowers the average power
dissipation of the IC by lowering the minimum duty cycle from 5% down to approximately 2%. (4) Output (pin 2) sourcing current. No diode, inductor or capacitor connected to output pin. (5) Feedback (pin 4) removed from output and connected to 0V. (6) Feedback (pin 4) removed from output and connected to +12V for the Adjustable, 3.3V, and 5V versions, and +25V for the 12V and 15V
versions, to force the output transistor OFF. (7) VIN= 40V (60V for the high voltage version). (8) Junction to ambient thermal resistance (no external heat sink) for the 5 lead TO-220 package mounted vertically, with ½ inch leads in a
socket, or on a PC board with minimum copper area. (9) Junction to ambient thermal resistance (no external heat sink) for the 5 lead TO-220 package mounted vertically, with ½ inch leads
soldered to a PC board containing approximately 4 square inches of copper area surrounding the leads. (10) Junction to ambient thermal resistance with approximately 1 square inch of pc board copper surrounding the leads. Additional copper
area will lower thermal resistance further. See thermal model in Switchers made Simple software. (11) If the DDPAK/TO-263 package is used, the thermal resistance can be reduced by increasing the PC board copper area thermally
connected to the package: Using 0.5 square inches of copper area, θJAis 50°C/W; with 1 square inch of copper area, θJAis 37°C/W;
and with 1.6 or more square inches of copper area, θJAis 32°C/W.
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ELECTRICAL CHARACTERISTICS ALL OUTPUT VOLTAGE VERSIONS (continued)
Specifications with standard type face are for TJ= 25°C, and those with boldface type apply over full Operating Temperature Range. Unless otherwise specified, VIN= 12V for the 3.3V, 5V, and Adjustable version, VIN= 25V for the 12V
version, and VIN= 30V for the 15V version. I
Symbol Parameter Conditions Typ
ON /OFF CONTROL Test Circuit Figure 25 and Figure 26
V
IH
V
IL
I
IH
I
IL
ON /OFF Pin Logic V Input Level
= 0V 1.4 2.2/2.4 2.2/2.4 V(Min)
OUT
V
= Nominal Output Voltage 1.2 1.0/0.8 1.0/0.8 V(Max)
OUT
ON /OFF Pin Input ON /OFF Pin = 5V (OFF) 12 μA Current
ON /OFF Pin = 0V (ON) 0 μA
LOAD
= 200 mA.
LM1575-XX
(1)
Limit
LM2575-XX
LM2575HV-XX
(2)
Limit
30 30 μA(Max)
10 10 μA(Max)
Units
(Limits)
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TYPICAL PERFORMANCE CHARACTERISTICS

(Circuit Figure 25 and Figure 26)
Normalized Output Voltage Line Regulation
Figure 9. Figure 10.
Dropout Voltage Current Limit
Figure 11. Figure 12.
Quiescent Current Quiescent Current
Figure 13. Figure 14.
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TYPICAL PERFORMANCE CHARACTERISTICS (continued)
(Circuit Figure 25 and Figure 26)
Oscillator Frequency Voltage
Figure 15. Figure 16.
Efficiency Minimum Operating Voltage
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Switch Saturation
Figure 17. Figure 18.
Quiescent Current Feedback Voltage
vs Duty Cycle vs Duty Cycle
Figure 19. Figure 20.
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TYPICAL PERFORMANCE CHARACTERISTICS (continued)
(Circuit Figure 25 and Figure 26)
Feedback Pin Current (TO-263) (See
Figure 21. Figure 22.
Switching Waveforms Load Transient Response
SNVS106E –MAY 1999–REVISED APRIL 2013
Maximum Power Dissipation
(1)
)
V
= 5V
OUT
A: Output Pin Voltage, 10V/div B: Output Pin Current, 1A/div C: Inductor Current, 0.5A/div D: Output Ripple Voltage, 20 mV/div, AC-Coupled
Horizontal Time Base: 5 μs/div
(1) If the DDPAK/TO-263 package is used, the thermal resistance can be reduced by increasing the PC board copper area thermally
connected to the package: Using 0.5 square inches of copper area, θJAis 50°C/W; with 1 square inch of copper area, θJAis 37°C/W;
and with 1.6 or more square inches of copper area, θJAis 32°C/W.
Figure 23. Figure 24.
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TEST CIRCUIT AND LAYOUT GUIDELINES

As in any switching regulator, layout is very important. Rapidly switching currents associated with wiring inductance generate voltage transients which can cause problems. For minimal inductance and ground loops, the length of the leads indicated by heavy lines should be kept as short as possible. Single-point grounding (as indicated) or ground plane construction should be used for best results. When using the Adjustable version, physically locate the programming resistors near the regulator, to keep the sensitive feedback wiring short.
CIN— 100 μF, 75V, Aluminum Electrolytic C
— 330 μF, 25V, Aluminum Electrolytic
OUT
D1 — Schottky, 11DQ06 L1 — 330 μH, PE-52627 (for 5V in, 3.3V out, use 100 μH, PE-92108)
Figure 25. Fixed Output Voltage Versions
where V
= 1.23V, R1 between 1k and 5k.
REF
R1 — 2k, 0.1% R2 — 6.12k, 0.1% Pin numbers are for the TO-220 package.
Figure 26. Adjustable Output Voltage Version
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LM2575 Series Buck Regulator Design Procedure

PROCEDURE (Fixed Output Voltage Versions) EXAMPLE (Fixed Output Voltage Versions)
Given: Given:
VIN(Max) = Maximum Input Voltage V
V
= Regulated Output Voltage (3.3V, 5V, 12V, or 15V)
OUT
I
(Max) = Maximum Load Current
LOAD
1. Inductor Selection (L1) 1. Inductor Selection (L1) A. Select the correct Inductor value selection guide from Figure 27, A. Use the selection guide shown in Figure 28.
Figure 28, Figure 29 and Figure 30 (Output voltages of 3.3V, 5V,
12V or 15V respectively). For other output voltages, see the design procedure of Figure 26 .
B. From the inductor value selection guide, identify the inductance region intersected by VIN(Max) and I inductor code for that region.
(Max), and note the
LOAD
C. Identify the inductor value from the inductor code, and select an appropriate inductor from the table shown in Table 2. Part numbers are listed for three inductor manufacturers. The inductor chosen must be rated for operation at the LM2575 switching frequency (52 kHz) and for a current rating of 1.15 × I information, see INDUCTOR SELECTION.
2. Output Capacitor Selection (C
OUT
. For additional inductor
LOAD
) 2. Output Capacitor Selection (C
A. The value of the output capacitor together with the inductor A. C
defines the dominate pole-pair of the switching regulator loop. For stable operation and an acceptable output ripple voltage, (approximately 1% of the output voltage) a value between 100 μF and 470 μF is recommended.
B. The capacitor's voltage rating should be at least 1.5 times greater than the output voltage. For a 5V regulator, a rating of at least 8V is appropriate, and a 10V or 15V rating is recommended.
Higher voltage electrolytic capacitors generally have lower ESR numbers, and for this reason it may be necessary to select a capacitor rated for a higher voltage than would normally be needed.
3. Catch Diode Selection (D1) 3. Catch Diode Selection (D1) A. The catch-diode current rating must be at least 1.2 times greater A. For this example, a 1A current rating is adequate.
than the maximum load current. Also, if the power supply design must withstand a continuous output short, the diode should have a current rating equal to the maximum current limit of the LM2575. The most stressful condition for this diode is an overload or shorted output condition.
B. The reverse voltage rating of the diode should be at least 1.25 times the maximum input voltage.
4. Input Capacitor (CIN) 4. Input Capacitor (CIN)
An aluminum or tantalum electrolytic bypass capacitor located close A 47 μF, 25V aluminum electrolytic capacitor located near the input to the regulator is needed for stable operation. and ground pins provides sufficient bypassing.
= 5V
OUT
VIN(Max) = 20V I
(Max) = 0.8A
LOAD
B. From the selection guide, the inductance area intersected by the 20V line and 0.8A line is L330.
C. Inductor value required is 330 μH. From the table in Table 2, choose AIE 415-0926, Pulse Engineering PE-52627, or RL1952.
)
OUT
= 100 μF to 470 μF standard aluminum electrolytic.
OUT
B. Capacitor voltage rating = 20V.
B. Use a 30V 1N5818 or SR103 Schottky diode, or any of the
suggested fast-recovery diodes shown in Table 1.
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Inductor Value Selection Guides

(For Continuous Mode Operation)
Figure 27. LM2575(HV)-3.3 Figure 28. LM2575(HV)-5.0
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Figure 29. LM2575(HV)-12 Figure 30. LM2575(HV)-15
Figure 31. LM2575(HV)-ADJ
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PROCEDURE (Adjustable Output Voltage Versions) EXAMPLE (Adjustable Output Voltage Versions)
Given: Given:
V
= Regulated Output Voltage V
OUT
OUT
= 10V VIN(Max) = Maximum Input Voltage VIN(Max) = 25V I
(Max) = Maximum Load Current I
LOAD
LOAD
(Max) = 1A
F = Switching Frequency (Fixed at 52 kHz) F = 52 kHz
1. Programming Output Voltage (Selecting R1 and R2, as shown 1. Programming Output Voltage (Selecting R1 and R2) in Figure 25 and Figure 26)
Use the following formula to select the appropriate resistor values.
(1)
R1can be between 1k and 5k. (For best temperature coefficient and
stability with time, use 1% metal film resistors)
R2 = 1k (8.13 1) = 7.13k, closest 1% value is 7.15k
(2)
2. Inductor Selection (L1) 2. Inductor Selection (L1) A. Calculate the inductor Volt • microsecond constant, A. Calculate E • T (V • μs)
E • T (V • μs), from the following formula:
(4)
B. Use the E • T value from the previous formula and match it with the E • T number on the vertical axis of the Inductor Value
Selection Guide shown in Figure 31. C. On the horizontal axis, select the maximum load current. D. Identify the inductance region intersected by the E • T value and
the maximum load current value, and note the inductor code for that region.
E. Identify the inductor value from the inductor code, and select an appropriate inductor from the table shown in Table 2. Part numbers are listed for three inductor manufacturers. The inductor chosen must be rated for operation at the LM2575 switching frequency (52 kHz) and for a current rating of 1.15 × I information, see INDUCTOR SELECTION.
3. Output Capacitor Selection (C
OUT
. For additional inductor
LOAD
) 3. Output Capacitor Selection (C
A. The value of the output capacitor together with the inductor A.
defines the dominate pole-pair of the switching regulator loop. For stable operation, the capacitor must satisfy the following requirement:
The above formula yields capacitor values between 10 μF and 2000 μF that will satisfy the loop requirements for stable operation. But to achieve an acceptable output ripple voltage, (approximately 1% of the output voltage) and transient response, the output capacitor may need to be several times larger than the above formula yields.
B. The capacitor's voltage rating should be at last 1.5 times greater than the output voltage. For a 10V regulator, a rating of at least 15V or more is recommended.
Higher voltage electrolytic capacitors generally have lower ESR numbers, and for this reason it may be necessary to select a capacitor rate for a higher voltage than would normally be needed.
(Continued) (Continued)
B. E • T = 115 V • μs C. I
(Max) = 1A
LOAD
D. Inductance Region = H470 E. Inductor Value = 470 μH Choose from AIE part #430-0634, Pulse
Engineering part #PE-53118, or Renco part #RL-1961.
)
OUT
However, for acceptable output ripple voltage select C
220 μF
OUT
(6)
C
= 220 μF electrolytic capacitor
OUT
(3)
(5)
(7)
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PROCEDURE (Adjustable Output Voltage Versions) EXAMPLE (Adjustable Output Voltage Versions)
4. Catch Diode Selection (D1) 4. Catch Diode Selection (D1) A. The catch-diode current rating must be at least 1.2 times greater A. For this example, a 3A current rating is adequate.
than the maximum load current. Also, if the power supply design must withstand a continuous output short, the diode should have a current rating equal to the maximum current limit of the LM2575. The most stressful condition for this diode is an overload or shorted output. See Table 1.
B. The reverse voltage rating of the diode should be at least 1.25 times the maximum input voltage.
5. Input Capacitor (CIN) 5. Input Capacitor (CIN)
An aluminum or tantalum electrolytic bypass capacitor located close A 100 μF aluminum electrolytic capacitor located near the input and to the regulator is needed for stable operation. ground pins provides sufficient bypassing.
B. Use a 40V MBR340 or 31DQ04 Schottky diode, or any of the suggested fast-recovery diodes in Table 1.
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To further simplify the buck regulator design procedure, TI is making available computer design software to be used with the Simple Switcher line of switching regulators. Switchers Made Simple (version 3.3) is available on a (3½) diskette for IBM compatible computers from a TI sales office in your area.
Table 1. Diode Selection Guide
V
R
20V 1N5817 1N5820
MBR120P MBR320 SR102 SR302
30V 1N5818 1N5821
MBR130P MBR330 11DQ03 31DQ03 SR103 SR303
40V 1N5819 IN5822
MBR140P MBR340 11DQ04 31DQ04 SR104 SR304
50V MBR150 MBR350
11DQ05 31DQ05 SR105 SR305
60V MBR160 MBR360
11DQ06 31DQ06 SR106 SR306
1A 3A 1A 3A
Schottky Fast Recovery
The following The following diodes are all diodes are all
rated to 100V: rated to 100V:
11DF1 31DF1 MUR110 MURD310 HER102 HER302
Table 2. Inductor Selection by Manufacturer's Part Number
Inductor Code Inductor Value Schott
L100 100 μH 67127000 PE-92108 RL2444 L150 150 μH 67127010 PE-53113 RL1954 L220 220 μH 67127020 PE-52626 RL1953 L330 330 μH 67127030 PE-52627 RL1952 L470 470 μH 67127040 PE-53114 RL1951
L680 680 μH 67127050 PE-52629 RL1950 H150 150 μH 67127060 PE-53115 RL2445 H220 220 μH 67127070 PE-53116 RL2446 H330 330 μH 67127080 PE-53117 RL2447 H470 470 μH 67127090 PE-53118 RL1961 H680 680 μH 67127100 PE-53119 RL1960
H1000 1000 μH 67127110 PE-53120 RL1959
(1) Schott Corp., (612) 475-1173, 1000 Parkers Lake Rd., Wayzata, MN 55391. (2) Pulse Engineering, (619) 674-8100, P.O. Box 12236, San Diego, CA 92112. (3) Renco Electronics Inc., (516) 586-5566, 60 Jeffryn Blvd. East, Deer Park, NY 11729.
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(1)
Pulse Eng.
(2)
Renco
(3)
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Table 2. Inductor Selection by Manufacturer's Part Number (continued)
Inductor Code Inductor Value Schott
H1500 1500 μH 67127120 PE-53121 RL1958 H2200 2200 μH 67127130 PE-53122 RL2448
(1)
Pulse Eng.
(2)
Renco
(3)

APPLICATION HINTS

INPUT CAPACITOR (CIN)

To maintain stability, the regulator input pin must be bypassed with at least a 47 μF electrolytic capacitor. The capacitor's leads must be kept short, and located near the regulator.
If the operating temperature range includes temperatures below 25°C, the input capacitor value may need to be larger. With most electrolytic capacitors, the capacitance value decreases and the ESR increases with lower temperatures and age. Paralleling a ceramic or solid tantalum capacitor will increase the regulator stability at cold temperatures. For maximum capacitor operating lifetime, the capacitor's RMS ripple current rating should be greater than
(8)

INDUCTOR SELECTION

All switching regulators have two basic modes of operation: continuous and discontinuous. The difference between the two types relates to the inductor current, whether it is flowing continuously, or if it drops to zero for a period of time in the normal switching cycle. Each mode has distinctively different operating characteristics, which can affect the regulator performance and requirements.
The LM2575 (or any of the Simple Switcher family) can be used for both continuous and discontinuous modes of operation.
The inductor value selection guides in Figure 27 through Figure 31 were designed for buck regulator designs of the continuous inductor current type. When using inductor values shown in the inductor selection guide, the peak-to-peak inductor ripple current will be approximately 20% to 30% of the maximum DC current. With relatively heavy load currents, the circuit operates in the continuous mode (inductor current always flowing), but under light load conditions, the circuit will be forced to the discontinuous mode (inductor current falls to zero for a period of time). This discontinuous mode of operation is perfectly acceptable. For light loads (less than approximately 200 mA) it may be desirable to operate the regulator in the discontinuous mode, primarily because of the lower inductor values required for the discontinuous mode.
The selection guide chooses inductor values suitable for continuous mode operation, but if the inductor value chosen is prohibitively high, the designer should investigate the possibility of discontinuous operation. The computer design software Switchers Made Simple will provide all component values for discontinuous (as well as continuous) mode of operation.
Inductors are available in different styles such as pot core, toriod, E-frame, bobbin core, etc., as well as different core materials, such as ferrites and powdered iron. The least expensive, the bobbin core type, consists of wire wrapped on a ferrite rod core. This type of construction makes for an inexpensive inductor, but since the magnetic flux is not completely contained within the core, it generates more electromagnetic interference (EMI). This EMI can cause problems in sensitive circuits, or can give incorrect scope readings because of induced voltages in the scope probe.
The inductors listed in the selection chart include ferrite pot core construction for AIE, powdered iron toroid for Pulse Engineering, and ferrite bobbin core for Renco.
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An inductor should not be operated beyond its maximum rated current because it may saturate. When an inductor begins to saturate, the inductance decreases rapidly and the inductor begins to look mainly resistive (the DC resistance of the winding). This will cause the switch current to rise very rapidly. Different inductor types have different saturation characteristics, and this should be kept in mind when selecting an inductor.
The inductor manufacturer's data sheets include current and energy limits to avoid inductor saturation.

INDUCTOR RIPPLE CURRENT

When the switcher is operating in the continuous mode, the inductor current waveform ranges from a triangular to a sawtooth type of waveform (depending on the input voltage). For a given input voltage and output voltage, the peak-to-peak amplitude of this inductor current waveform remains constant. As the load current rises or falls, the entire sawtooth current waveform also rises or falls. The average DC value of this waveform is equal to the DC load current (in the buck regulator configuration).
If the load current drops to a low enough level, the bottom of the sawtooth current waveform will reach zero, and the switcher will change to a discontinuous mode of operation. This is a perfectly acceptable mode of operation. Any buck switching regulator (no matter how large the inductor value is) will be forced to run discontinuous if the load current is light enough.

OUTPUT CAPACITOR

An output capacitor is required to filter the output voltage and is needed for loop stability. The capacitor should be located near the LM2575 using short pc board traces. Standard aluminum electrolytics are usually adequate, but low ESR types are recommended for low output ripple voltage and good stability. The ESR of a capacitor depends on many factors, some which are: the value, the voltage rating, physical size and the type of construction. In general, low value or low voltage (less than 12V) electrolytic capacitors usually have higher ESR numbers.
The amount of output ripple voltage is primarily a function of the ESR (Equivalent Series Resistance) of the output capacitor and the amplitude of the inductor ripple current (ΔI
). (See INDUCTOR RIPPLE CURRENT).
IND
The lower capacitor values (220 μF–680 μF) will allow typically 50 mV to 150 mV of output ripple voltage, while larger-value capacitors will reduce the ripple to approximately 20 mV to 50 mV.
Output Ripple Voltage = (ΔI
) (ESR of C
IND
) (9)
OUT
To further reduce the output ripple voltage, several standard electrolytic capacitors may be paralleled, or a higher-grade capacitor may be used. Such capacitors are often called “high-frequency,” “low-inductance,” or “low-ESR.” These will reduce the output ripple to 10 mV or 20 mV. However, when operating in the continuous mode, reducing the ESR below 0.05Ω can cause instability in the regulator.
Tantalum capacitors can have a very low ESR, and should be carefully evaluated if it is the only output capacitor. Because of their good low temperature characteristics, a tantalum can be used in parallel with aluminum electrolytics, with the tantalum making up 10% or 20% of the total capacitance.
The capacitor's ripple current rating at 52 kHz should be at least 50% higher than the peak-to-peak inductor ripple current.

CATCH DIODE

Buck regulators require a diode to provide a return path for the inductor current when the switch is off. This diode should be located close to the LM2575 using short leads and short printed circuit traces.
Because of their fast switching speed and low forward voltage drop, Schottky diodes provide the best efficiency, especially in low output voltage switching regulators (less than 5V). Fast-Recovery, High-Efficiency, or Ultra-Fast Recovery diodes are also suitable, but some types with an abrupt turn-off characteristic may cause instability and EMI problems. A fast-recovery diode with soft recovery characteristics is a better choice. Standard 60 Hz diodes (example: 1N4001 or 1N5400, and so on.) are also not suitable. See Table 1 for Schottky and “soft” fast­recovery diode selection guide.
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OUTPUT VOLTAGE RIPPLE AND TRANSIENTS

The output voltage of a switching power supply will contain a sawtooth ripple voltage at the switcher frequency, typically about 1% of the output voltage, and may also contain short voltage spikes at the peaks of the sawtooth waveform.
The output ripple voltage is due mainly to the inductor sawtooth ripple current multiplied by the ESR of the output capacitor. (See INDUCTOR SELECTION)
The voltage spikes are present because of the fast switching action of the output switch, and the parasitic inductance of the output filter capacitor. To minimize these voltage spikes, special low inductance capacitors can be used, and their lead lengths must be kept short. Wiring inductance, stray capacitance, as well as the scope probe used to evaluate these transients, all contribute to the amplitude of these spikes.
An additional small LC filter (20 μH & 100 μF) can be added to the output (as shown in Figure 37) to further reduce the amount of output ripple and transients. A 10 × reduction in output ripple voltage and transients is possible with this filter.

FEEDBACK CONNECTION

The LM2575 (fixed voltage versions) feedback pin must be wired to the output voltage point of the switching power supply. When using the adjustable version, physically locate both output voltage programming resistors near the LM2575 to avoid picking up unwanted noise. Avoid using resistors greater than 100 kΩ because of the increased chance of noise pickup.

ON /OFF INPUT

For normal operation, the ON /OFF pin should be grounded or driven with a low-level TTL voltage (typically below 1.6V). To put the regulator into standby mode, drive this pin with a high-level TTL or CMOS signal. The ON /OFF pin can be safely pulled up to +VINwithout a resistor in series with it. The ON /OFF pin should not be left open.

GROUNDING

To maintain output voltage stability, the power ground connections must be low-impedance (see Figure 26). For the TO-3 style package, the case is ground. For the 5-lead TO-220 style package, both the tab and pin 3 are ground and either connection may be used, as they are both part of the same copper lead frame.
With the CDIP or SOIC packages, all the pins labeled ground, power ground, or signal ground should be soldered directly to wide printed circuit board copper traces. This assures both low inductance connections and good thermal properties.

HEAT SINK/THERMAL CONSIDERATIONS

In many cases, no heat sink is required to keep the LM2575 junction temperature within the allowed operating range. For each application, to determine whether or not a heat sink will be required, the following must be identified:
1. Maximum ambient temperature (in the application).
2. Maximum regulator power dissipation (in application).
3. Maximum allowed junction temperature (150°C for the LM1575 or 125°C for the LM2575). For a safe, conservative design, a temperature approximately 15°C cooler than the maximum temperature should be selected.
4. LM2575 package thermal resistances θJAand θJC.
Total power dissipated by the LM2575 can be estimated as follows:
PD= (VIN) (IQ) + (VO/VIN) (I
LOAD
) (V
SAT
)
where
IQ(quiescent current) and V
VINis the applied minimum input voltage,
VOis the regulated output voltage
and I
is the load current. (10)
LOAD
can be found in the Characteristic Curves shown previously,
SAT
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The dynamic losses during turn-on and turn-off are negligible if a Schottky type catch diode is used. When no heat sink is used, the junction temperature rise can be determined by the following:
ΔTJ= (PD) (θJA) (11)
To arrive at the actual operating junction temperature, add the junction temperature rise to the maximum ambient temperature.
TJ= ΔTJ+ T
A
(12)
If the actual operating junction temperature is greater than the selected safe operating junction temperature determined in step 3, then a heat sink is required.
When using a heat sink, the junction temperature rise can be determined by the following:
ΔTJ= (PD) (θJC+ θ
interface
+ θ
) (13)
Heat sink
The operating junction temperature will be:
TJ= TA+ ΔT
J
(14)
As shown in Equation 14, if the actual operating junction temperature is greater than the selected safe operating junction temperature, then a larger heat sink is required (one that has a lower thermal resistance).
When using the LM2575 in the plastic CDIP or surface mount SOIC packages, several items about the thermal properties of the packages should be understood. The majority of the heat is conducted out of the package through the leads, with a minor portion through the plastic parts of the package. Since the lead frame is solid copper, heat from the die is readily conducted through the leads to the printed circuit board copper, which is acting as a heat sink.
For best thermal performance, the ground pins and all the unconnected pins should be soldered to generous amounts of printed circuit board copper, such as a ground plane. Large areas of copper provide the best transfer of heat to the surrounding air. Copper on both sides of the board is also helpful in getting the heat away from the package, even if there is no direct copper contact between the two sides. Thermal resistance numbers as low as 40°C/W for the SOIC package, and 30°C/W for the CDIP package can be realized with a carefully engineered pc board.
Included on the Switchers Made Simple design software is a more precise (non-linear) thermal model that can be used to determine junction temperature with different input-output parameters or different component values. It can also calculate the heat sink thermal resistance required to maintain the regulators junction temperature below the maximum operating temperature.

ADDITIONAL APPLICATIONS

INVERTING REGULATOR

Figure 32 shows a LM2575-12 in a buck-boost configuration to generate a negative 12V output from a positive
input voltage. This circuit bootstraps the regulator's ground pin to the negative output voltage, then by grounding the feedback pin, the regulator senses the inverted output voltage and regulates it to 12V.
For an input voltage of 12V or more, the maximum available output current in this configuration is approximately
0.35A. At lighter loads, the minimum input voltage required drops to approximately 4.7V. The switch currents in this buck-boost configuration are higher than in the standard buck-mode design, thus
lowering the available output current. Also, the start-up input current of the buck-boost converter is higher than the standard buck-mode regulator, and this may overload an input power source with a current limit less than
1.5A. Using a delayed turn-on or an undervoltage lockout circuit (described in the NEGATIVE BOOST
REGULATOR section) would allow the input voltage to rise to a high enough level before the switcher would be
allowed to turn on. Because of the structural differences between the buck and the buck-boost regulator topologies, the buck
regulator design procedure section cannot be used to select the inductor or the output capacitor. The recommended range of inductor values for the buck-boost design is between 68 μH and 220 μH, and the output capacitor values must be larger than what is normally required for buck designs. Low input voltages or high output currents require a large value output capacitor (in the thousands of micro Farads).
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The peak inductor current, which is the same as the peak switch current, can be calculated from the following formula:
where
f
= 52 kHz. (15)
osc
Under normal continuous inductor current operating conditions, the minimum VINrepresents the worst case. Select an inductor that is rated for the peak current anticipated.
Also, the maximum voltage appearing across the regulator is the absolute sum of the input and output voltage. For a 12V output, the maximum input voltage for the LM2575 is +28V, or +48V for the LM2575HV.
The Switchers Made Simple (version 3.3) design software can be used to determine the feasibility of regulator designs using different topologies, different input-output parameters, different components, and so on.
Figure 32. Inverting Buck-Boost Develops 12V

NEGATIVE BOOST REGULATOR

Another variation on the buck-boost topology is the negative boost configuration. The circuit in Figure 33 accepts an input voltage ranging from 5V to 12V and provides a regulated 12V output. Input voltages greater than
12V will cause the output to rise above 12V, but will not damage the regulator. Because of the boosting function of this type of regulator, the switch current is relatively high, especially at low
input voltages. Output load current limitations are a result of the maximum current rating of the switch. Also, boost regulators can not provide current limiting load protection in the event of a shorted load, so some other means (such as a fuse) may be necessary.
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LM2575-12
2
4
1
3 5
+
1N5817
+
C
OUT
1000 PF
Feedback
Output
V
IN
C
IN
100 PF
GND
150 PH
V
OUT
= -12V
-V
IN
-5V to -12V
Low ESR
ON/OFF
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Typical Load Current 200 mA for VIN= 5.2V 500 mA for VIN= 7V Pin numbers are for TO-220 package.
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Figure 33. Negative Boost

UNDERVOLTAGE LOCKOUT

In some applications it is desirable to keep the regulator off until the input voltage reaches a certain threshold. An undervoltage lockout circuit which accomplishes this task is shown in Figure 34, while Figure 35 shows the same circuit applied to a buck-boost configuration. These circuits keep the regulator off until the input voltage reaches a predetermined level.
VTH≈ VZ1+ 2VBE(Q1) (16)

DELAYED STARTUP

The ON /OFF pin can be used to provide a delayed startup feature as shown in Figure 36. With an input voltage of 20V and for the part values shown, the circuit provides approximately 10 ms of delay time before the circuit begins switching. Increasing the RC time constant can provide longer delay times. But excessively large RC time constants can cause problems with input voltages that are high in 60 Hz or 120 Hz ripple, by coupling the ripple into the ON /OFF pin.

ADJUSTABLE OUTPUT, LOW-RIPPLE POWER SUPPLY

A 1A power supply that features an adjustable output voltage is shown in Figure 37. An additional L-C filter that reduces the output ripple by a factor of 10 or more is included in this circuit.
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Complete circuit not shown. Pin numbers are for the TO-220 package.
Figure 34. Undervoltage Lockout for Buck Circuit
Complete circuit not shown (see Figure 32). Pin numbers are for the TO-220 package.
Figure 35. Undervoltage Lockout
for Buck-Boost Circuit
Complete circuit not shown. Pin numbers are for the TO-220 package.
Figure 36. Delayed Startup
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Pin numbers are for the TO-220 package.
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Figure 37. 1.2V to 55V Adjustable 1A Power Supply with Low Output Ripple

Definition of Terms

BUCK REGULATORA switching regulator topology in which a higher voltage is converted to a lower voltage.
Also known as a step-down switching regulator.
BUCK-BOOST REGULATORA switching regulator topology in which a positive voltage is converted to a
negative voltage without a transformer.
DUTY CYCLE (D)Ratio of the output switch's on-time to the oscillator period.
CATCH DIODE OR CURRENT STEERING DIODEThe diode which provides a return path for the load current
when the LM2575 switch is OFF.
EFFICIENCY (η)The proportion of input power actually delivered to the load.
CAPACITOR EQUIVALENT SERIES RESISTANCE (ESR)The purely resistive component of a real capacitor's
impedance (see Figure 38). It causes power loss resulting in capacitor heating, which directly affects the capacitor's operating lifetime. When used as a switching regulator output filter, higher ESR values result in higher output ripple voltages.
Figure 38. Simple Model of a Real Capacitor
Most standard aluminum electrolytic capacitors in the 100 μF–1000 μF range have 0.5Ω to
0.1Ω ESR. Higher-grade capacitors (“low-ESR”, “high-frequency”, or “low-inductance”') in the 100 μF–1000 μF range generally have ESR of less than 0.15Ω.
EQUIVALENT SERIES INDUCTANCE (ESL)The pure inductance component of a capacitor (see Figure 38).
The amount of inductance is determined to a large extent on the capacitor's construction. In a buck regulator, this unwanted inductance causes voltage spikes to appear on the output.
OUTPUT RIPPLE VOLTAGEThe AC component of the switching regulator's output voltage. It is usually
dominated by the output capacitor's ESR multiplied by the inductor's ripple current (ΔI
). The peak-to-
IND
peak value of this sawtooth ripple current can be determined by reading INDUCTOR RIPPLE CURRENT.
(17)
(18)
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CAPACITOR RIPPLE CURRENTRMS value of the maximum allowable alternating current at which a capacitor
can be operated continuously at a specified temperature.
STANDBY QUIESCENT CURRENT (I
)Supply current required by the LM2575 when in the standby mode
STBY
(ON /OFF pin is driven to TTL-high voltage, thus turning the output switch OFF).
INDUCTOR RIPPLE CURRENT (ΔI
)The peak-to-peak value of the inductor current waveform, typically a
IND
sawtooth waveform when the regulator is operating in the continuous mode (vs. discontinuous mode).
CONTINUOUS/DISCONTINUOUS MODE OPERATIONRelates to the inductor current. In the continuous mode,
the inductor current is always flowing and never drops to zero, vs. the discontinuous mode, where the inductor current drops to zero for a period of time in the normal switching cycle.
INDUCTOR SATURATIONThe condition which exists when an inductor cannot hold any more magnetic flux.
When an inductor saturates, the inductor appears less inductive and the resistive component dominates. Inductor current is then limited only by the DC resistance of the wire and the available source current.
OPERATING VOLT MICROSECOND CONSTANT (E•Top)The product (in VoIt•μs) of the voltage applied to the
inductor and the time the voltage is applied. This E•Topconstant is a measure of the energy handling capability of an inductor and is dependent upon the type of core, the core area, the number of turns, and the duty cycle.
Copyright © 1999–2013, Texas Instruments Incorporated Submit Documentation Feedback 25
Product Folder Links: LM1575 LM2575-N LM2575HV
Page 26
LM1575, LM2575-N, LM2575HV
SNVS106E –MAY 1999–REVISED APRIL 2013
www.ti.com

REVISION HISTORY

Changes from Revision D (April 2013) to Revision E Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 25
26 Submit Documentation Feedback Copyright © 1999–2013, Texas Instruments Incorporated
Product Folder Links: LM1575 LM2575-N LM2575HV
Page 27
PACKAGE OPTION ADDENDUM
www.ti.com
PACKAGING INFORMATION
Orderable Device Status
LM2575HVMX-5.0 ACTIVE SOIC DW 24 1000 TBD Call TI Call TI -40 to 125 LM2575HVM
LM2575HVMX-5.0/NOPB ACTIVE SOIC DW 24 1000 Green (RoHS
LM2575HVN-5.0 ACTIVE PDIP NBG 16 20 TBD Call TI Call TI -40 to 125 LM2575HVN
LM2575HVN-5.0/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS
LM2575HVN-ADJ ACTIVE PDIP NBG 16 20 TBD Call TI Call TI -40 to 125 LM2575HVN
LM2575HVN-ADJ/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS
LM2575HVS-12 ACTIVE DDPAK/
LM2575HVS-12/NOPB ACTIVE DDPAK/
LM2575HVS-15 ACTIVE DDPAK/
LM2575HVS-15/NOPB ACTIVE DDPAK/
LM2575HVS-3.3 ACTIVE DDPAK/
LM2575HVS-3.3/NOPB ACTIVE DDPAK/
LM2575HVS-5.0 ACTIVE DDPAK/
LM2575HVS-5.0/NOPB ACTIVE DDPAK/
LM2575HVS-ADJ ACTIVE DDPAK/
LM2575HVS-ADJ/NOPB ACTIVE DDPAK/
LM2575HVSX-15 ACTIVE DDPAK/
Package Type Package
(1)
TO-263
TO-263
TO-263
TO-263
TO-263
TO-263
TO-263
TO-263
TO-263
TO-263
TO-263
Drawing
Pins Package
Qty
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS
KTT 5 45 Pb-Free (RoHS
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS
KTT 5 45 Pb-Free (RoHS
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS
KTT 5 45 Pb-Free (RoHS
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS
KTT 5 45 Pb-Free (RoHS
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS
KTT 5 45 Pb-Free (RoHS
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575HVS
Eco Plan
(2)
& no Sb/Br)
& no Sb/Br)
& no Sb/Br)
Exempt)
Exempt)
Exempt)
Exempt)
Exempt)
Lead/Ball Finish MSL Peak Temp
(3)
CU SN Level-3-260C-168 HR -40 to 125 LM2575HVM
CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVN
CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVN
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
Op Temp (°C) Top-Side Markings
11-Apr-2013
Samples
(4)
-5.0 P+
-5.0 P+
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-12 P+
-12 P+
-15 P+
-15 P+
-3.3 P+
-3.3 P+
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-15 P+
Addendum-Page 1
Page 28
PACKAGE OPTION ADDENDUM
www.ti.com
Orderable Device Status
LM2575HVSX-15/NOPB ACTIVE DDPAK/
LM2575HVSX-3.3 ACTIVE DDPAK/
Package Type Package
(1)
TO-263
Drawing
Qty
KTT 5 500 Pb-Free (RoHS
Pins Package
Eco Plan
(2)
Lead/Ball Finish MSL Peak Temp
(3)
Op Temp (°C) Top-Side Markings
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
Exempt)
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575HVS
TO-263
LM2575HVSX-3.3/NOPB ACTIVE DDPAK/
TO-263
LM2575HVSX-5.0 ACTIVE DDPAK/
KTT 5 500 Pb-Free (RoHS
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
Exempt)
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575HVS
TO-263
LM2575HVSX-5.0/NOPB ACTIVE DDPAK/
TO-263
LM2575HVSX-ADJ ACTIVE DDPAK/
KTT 5 500 Pb-Free (RoHS
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
Exempt)
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575HVS
TO-263
LM2575HVSX-ADJ/NOPB ACTIVE DDPAK/
TO-263
KTT 5 500 Pb-Free (RoHS
Exempt)
CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS
LM2575HVT-12 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT
LM2575HVT-12/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2575HVT
LM2575HVT-12/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575HVT
& no Sb/Br)
LM2575HVT-12/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT
& no Sb/Br)
LM2575HVT-15 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT
LM2575HVT-15/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2575HVT
LM2575HVT-15/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575HVT
& no Sb/Br)
LM2575HVT-15/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT
& no Sb/Br)
LM2575HVT-3.3 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT
LM2575HVT-3.3/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575HVT
& no Sb/Br)
LM2575HVT-3.3/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT
& no Sb/Br)
11-Apr-2013
Samples
(4)
-15 P+
-3.3 P+
-3.3 P+
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-12 P+
-12 P+
-12 P+
-12 P+
-15 P+
-15 P+
-15 P+
-15 P+
-3.3 P+
-3.3 P+
-3.3 P+
Addendum-Page 2
Page 29
PACKAGE OPTION ADDENDUM
www.ti.com
Orderable Device Status
Package Type Package
(1)
Drawing
Pins Package
Qty
Eco Plan
(2)
Lead/Ball Finish MSL Peak Temp
(3)
Op Temp (°C) Top-Side Markings
LM2575HVT-5.0 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT
LM2575HVT-5.0/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2575HVT
LM2575HVT-5.0/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575HVT
& no Sb/Br)
LM2575HVT-5.0/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT
& no Sb/Br)
LM2575HVT-ADJ ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT
LM2575HVT-ADJ/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2575HVT
LM2575HVT-ADJ/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575HVT
& no Sb/Br)
LM2575HVT-ADJ/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT
& no Sb/Br)
LM2575M-5.0 ACTIVE SOIC DW 24 30 TBD Call TI Call TI -40 to 125 LM2575M
LM2575M-5.0/NOPB ACTIVE SOIC DW 24 30 Green (RoHS
CU SN Level-3-260C-168 HR -40 to 125 LM2575M
& no Sb/Br)
LM2575M-ADJ ACTIVE SOIC DW 24 30 TBD Call TI Call TI -40 to 125 LM2575M
LM2575M-ADJ/NOPB ACTIVE SOIC DW 24 30 Green (RoHS
CU SN Level-3-260C-168 HR -40 to 125 LM2575M
& no Sb/Br)
LM2575MX-5.0 ACTIVE SOIC DW 24 1000 TBD Call TI Call TI -40 to 125 LM2575M
LM2575MX-5.0/NOPB ACTIVE SOIC DW 24 1000 Green (RoHS
CU SN Level-3-260C-168 HR -40 to 125 LM2575M
& no Sb/Br)
LM2575MX-ADJ ACTIVE SOIC DW 24 1000 TBD Call TI Call TI -40 to 125 LM2575M
LM2575MX-ADJ/NOPB ACTIVE SOIC DW 24 1000 Green (RoHS
CU SN Level-3-260C-168 HR -40 to 125 LM2575M
& no Sb/Br)
LM2575N-5.0 ACTIVE PDIP NBG 16 20 TBD Call TI Call TI -40 to 125 LM2575N
LM2575N-5.0/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575N
& no Sb/Br)
11-Apr-2013
Samples
(4)
-5.0 P+
-5.0 P+
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-ADJ P+
-ADJ P+
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-5.0 P+
-5.0 P+
Addendum-Page 3
Page 30
PACKAGE OPTION ADDENDUM
www.ti.com
Orderable Device Status
Package Type Package
(1)
Drawing
Pins Package
Qty
LM2575N-ADJ ACTIVE PDIP NBG 16 20 TBD Call TI Call TI -40 to 125 LM2575N
LM2575N-ADJ/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS
LM2575S-12 ACTIVE DDPAK/
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575S-12/NOPB ACTIVE DDPAK/
KTT 5 45 Pb-Free (RoHS
TO-263
LM2575S-15 ACTIVE DDPAK/
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575S-15/NOPB ACTIVE DDPAK/
KTT 5 45 Pb-Free (RoHS
TO-263
LM2575S-3.3 ACTIVE DDPAK/
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575S-3.3/NOPB ACTIVE DDPAK/
KTT 5 45 Pb-Free (RoHS
TO-263
LM2575S-5.0 ACTIVE DDPAK/
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575S-5.0/NOPB ACTIVE DDPAK/
KTT 5 45 Pb-Free (RoHS
TO-263
LM2575S-ADJ ACTIVE DDPAK/
KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575S-ADJ/NOPB ACTIVE DDPAK/
KTT 5 45 Pb-Free (RoHS
TO-263
LM2575SX-12 ACTIVE DDPAK/
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575SX-12/NOPB ACTIVE DDPAK/
KTT 5 500 Pb-Free (RoHS
TO-263
LM2575SX-15 ACTIVE DDPAK/
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575SX-15/NOPB ACTIVE DDPAK/
KTT 5 500 Pb-Free (RoHS
TO-263
LM2575SX-3.3 ACTIVE DDPAK/
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575SX-3.3/NOPB ACTIVE DDPAK/
KTT 5 500 Pb-Free (RoHS
TO-263
Eco Plan
(2)
& no Sb/Br)
Exempt)
Exempt)
Exempt)
Exempt)
Exempt)
Exempt)
Exempt)
Exempt)
Lead/Ball Finish MSL Peak Temp
(3)
Op Temp (°C) Top-Side Markings
CU SN Level-1-NA-UNLIM -40 to 125 LM2575N
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
11-Apr-2013
Samples
(4)
-ADJ P+
-ADJ P+
-12 P+
-12 P+
-15 P+
-15 P+
-3.3 P+
-3.3 P+
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-12 P+
-12 P+
-15 P+
-15 P+
-3.3 P+
-3.3 P+
Addendum-Page 4
Page 31
PACKAGE OPTION ADDENDUM
www.ti.com
Orderable Device Status
LM2575SX-5.0 ACTIVE DDPAK/
Package Type Package
(1)
Drawing
Pins Package
Qty
Eco Plan
(2)
Lead/Ball Finish MSL Peak Temp
(3)
Op Temp (°C) Top-Side Markings
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575SX-5.0/NOPB ACTIVE DDPAK/
TO-263
LM2575SX-ADJ ACTIVE DDPAK/
KTT 5 500 Pb-Free (RoHS
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
Exempt)
KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575S
TO-263
LM2575SX-ADJ/NOPB ACTIVE DDPAK/
TO-263
KTT 5 500 Pb-Free (RoHS
Exempt)
CU SN Level-3-245C-168 HR -40 to 125 LM2575S
LM2575T-12 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T
LM2575T-12/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2575T
LM2575T-12/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575T
& no Sb/Br)
LM2575T-12/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575T
& no Sb/Br)
LM2575T-15 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T
LM2575T-15/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575T
& no Sb/Br)
LM2575T-15/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575T
& no Sb/Br)
LM2575T-3.3 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T
LM2575T-3.3/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575T
& no Sb/Br)
LM2575T-3.3/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM -40 to 125 LM2575T
& no Sb/Br)
LM2575T-5.0 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T
LM2575T-5.0/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2575T
LM2575T-5.0/LF02 ACTIVE TO-220 NEB 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575T
& no Sb/Br)
LM2575T-5.0/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
CU SN Level-1-NA-UNLIM LM2575T
& no Sb/Br)
11-Apr-2013
Samples
(4)
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-12 P+
-12 P+
-12 P+
-12 P+
-15 P+
-15 P+
-15 P+
-3.3 P+
-3.3 P+
-3.3 P+
-5.0 P+
-5.0 P+
-5.0 P+
-5.0 P+
Addendum-Page 5
Page 32
PACKAGE OPTION ADDENDUM
www.ti.com
Orderable Device Status
LM2575T-5.0/LF04 ACTIVE TO-220 NEB 5 45 Green (RoHS
LM2575T-5.0/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
LM2575T-ADJ ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T
LM2575T-ADJ/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2575T
LM2575T-ADJ/LF02 ACTIVE TO-220 NEB 5 45 Green (RoHS
LM2575T-ADJ/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS
LM2575T-ADJ/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device.
Package Type Package
(1)
Drawing
Pins Package
Qty
Eco Plan
(2)
& no Sb/Br)
& no Sb/Br)
& no Sb/Br)
& no Sb/Br)
& no Sb/Br)
Lead/Ball Finish MSL Peak Temp
(3)
CU SN Level-1-NA-UNLIM LM2575T
CU SN Level-1-NA-UNLIM -40 to 125 LM2575T
CU SN Level-1-NA-UNLIM LM2575T
CU SN Level-1-NA-UNLIM LM2575T
CU SN Level-1-NA-UNLIM -40 to 125 LM2575T
Op Temp (°C) Top-Side Markings
(4)
-5.0 P+
-5.0 P+
-ADJ P+
-ADJ P+
-ADJ P+
-ADJ P+
-ADJ P+
11-Apr-2013
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a
continuation of the previous line and the two combined represent the entire Top-Side Marking for that device.
Samples
Addendum-Page 6
Page 33
PACKAGE OPTION ADDENDUM
www.ti.com
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
11-Apr-2013
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 7
Page 34
PACKAGE MATERIALS INFORMATION
www.ti.com 8-Apr-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
LM2575HVMX-5.0 SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1
LM2575HVMX-5.0/NOPB SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1
LM2575HVSX-15 DDPAK/
TO-263
LM2575HVSX-15/NOPB DDPAK/
TO-263
LM2575HVSX-3.3 DDPAK/
TO-263
LM2575HVSX-3.3/NOPB DDPAK/
TO-263
LM2575HVSX-5.0 DDPAK/
TO-263
LM2575HVSX-5.0/NOPB DDPAK/
TO-263
LM2575HVSX-ADJ DDPAK/
TO-263
LM2575HVSX-ADJ/NOPB DDPAK/
TO-263
LM2575MX-5.0 SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1
LM2575MX-5.0/NOPB SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1
Type
Package Drawing
Pins SPQ Reel
Diameter
(mm)
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
Reel
Width
W1 (mm)
A0
(mm)B0(mm)K0(mm)P1(mm)W(mm)
Pin1
Quadrant
Pack Materials-Page 1
Page 35
PACKAGE MATERIALS INFORMATION
www.ti.com 8-Apr-2013
Device Package
LM2575MX-ADJ SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1
LM2575MX-ADJ/NOPB SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1
LM2575SX-12 DDPAK/
TO-263
LM2575SX-12/NOPB DDPAK/
TO-263
LM2575SX-15 DDPAK/
TO-263
LM2575SX-15/NOPB DDPAK/
TO-263
LM2575SX-3.3 DDPAK/
TO-263
LM2575SX-3.3/NOPB DDPAK/
TO-263
LM2575SX-5.0 DDPAK/
TO-263
LM2575SX-5.0/NOPB DDPAK/
TO-263
LM2575SX-ADJ DDPAK/
TO-263
LM2575SX-ADJ/NOPB DDPAK/
TO-263
Type
Package Drawing
Pins SPQ Reel
Diameter
(mm)
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
Reel
Width
W1 (mm)
A0
(mm)B0(mm)K0(mm)P1(mm)W(mm)
Pin1
Quadrant
Pack Materials-Page 2
Page 36
PACKAGE MATERIALS INFORMATION
www.ti.com 8-Apr-2013
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LM2575HVMX-5.0 SOIC DW 24 1000 367.0 367.0 45.0
LM2575HVMX-5.0/NOPB SOIC DW 24 1000 367.0 367.0 45.0
LM2575HVSX-15 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575HVSX-15/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575HVSX-3.3 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575HVSX-3.3/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575HVSX-5.0 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575HVSX-5.0/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575HVSX-ADJ DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575HVSX-ADJ/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575MX-5.0 SOIC DW 24 1000 367.0 367.0 45.0
LM2575MX-5.0/NOPB SOIC DW 24 1000 367.0 367.0 45.0
LM2575MX-ADJ SOIC DW 24 1000 367.0 367.0 45.0
LM2575MX-ADJ/NOPB SOIC DW 24 1000 367.0 367.0 45.0
LM2575SX-12 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-12/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-15 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-15/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-3.3 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-3.3/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-5.0 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-5.0/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-ADJ DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LM2575SX-ADJ/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
Pack Materials-Page 3
Page 37
NDH0005D
MECHANICAL DATA
www.ti.com
Page 38
NBG0016G
MECHANICAL DATA
www.ti.com
Page 39
Page 40
KTT0005B
MECHANICAL DATA
BOTTOM SIDE OF PACKAGE
TS5B (Rev D)
www.ti.com
Page 41
NEB0005B
MECHANICAL DATA
www.ti.com
Page 42
NEB0005F
MECHANICAL DATA
www.ti.com
Page 43
Page 44
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