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MIC39300-2.5BT
Datasheet (MICREL)
12 pgs110.36 Kb0

Datasheet MIC39300-2.5BT, MIC39300-2.5BU, MIC39301-2.5BT, MIC39301-2.5BU Datasheet (MICREL)

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Page 1
MIC39300/39301 Micrel
MIC39301-2.5
IN OUT
GND
47µF
V
IN
3.3V
V
OUT
2.5V
EN FLG
ERROR FLAG OUTPUT
ENABLE
SHUTDOWN
100kΩ
MIC39300/39301
3A Low-Voltage Low-Dropout Regulator
General Description
The MIC39300 and MIC39301 are 3.0A low-dropout linear voltage regulators that provide a low voltage, high-current output with a minimum of external components. Utilizing Micrel’s proprietary Super βeta PNP™ pass element, the MIC39300/1 offers extremely low dropout (typically 400mV at
3.0A) and low ground current (typically 36mA at 3.0A). The MIC39300/1 is ideal for PC add-in cards that need to
convert from standard 5V or 3.3V down to new, lower core voltages. A guaranteed maximum dropout voltage of 500mV over all operating conditions allows the MIC39300/1 to pro­vide 2.5V from a supply as low as 3V. The MIC39300/1 also has fast transient response for heavy switching applications. The device requires only 47µF of output capacitance to maintain stability and achieve fast transient response
The MIC39300/1 is fully protected with overcurrent limiting, thermal shutdown, reversed-battery protection, reversed­leakage protection, and reversed-lead insertion. The MIC39301 offers a TTL-logic compatible enable pin and an error flag that indicates under voltage and over current conditions. Offered in fixed voltages, the MIC39300/1 comes in the TO-220 and TO-263 packages and is an ideal upgrade to older, NPN-based linear voltage regulators.
Features
• 3.0A minimum guaranteed output current
• 500mV maximum dropout voltage over temperature
Ideal for 3.0V to 2.5V conversion
• 1% initial accuracy
• Low ground current
• Current limiting and Thermal shutdown
• Reversed-battery protection
• Reversed-leakage protection
• Fast transient response
• TO-263 and TO-220 packaging
• TTL/CMOS compatible enable pin (MIC39301 only)
• Error flag output (MIC39301 only)
Applications
• LDO linear regulator for PC add-in cards
• High-efficiency linear power supplies
• SMPS post regulator
• Multimedia and PC processor supplies
• Low-voltage microcontrollers
• StrongARM™ processor supply
Ordering Information
Part Number Voltage Junction Temp. Range Package
MIC39300-2.5BT 2.5V –40°C to +125°C 3-lead TO-220 MIC39300-2.5BU 2.5V –40°C to +125°C 3-lead TO-263 MIC39301-2.5BT 2.5V –40°C to +125°C 5-lead TO-220 MIC39301-2.5BU 2.5V –40°C to +125°C 5-lead TO-263
Typical Application
MIC39300-2.5
V
IN OUT
IN
3.3V GND
StrongARM is a trademark of Advanced RISC Machines, Ltd.
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
MIC39300
March 2000 1 MIC39300/39301
47µF
V
OUT
2.5V
MIC39301
Page 2
MIC39300/39301 Micrel
Pin Configuration
TAB
TAB
MIC39300-x.xBT
TO-220-3 (T)
MIC39301-x.xBT
TO-220-5 (T)
3 OUT 2 GND 1IN
5 FLG 4 OUT 3 GND 2IN 1EN
TAB
MIC39300-x.xBU
TO-263-3 (U)
TAB
MIC39301-x.xBU
TO-263-5 (U)
3 OUT 2 GND 1IN
5 FLG 4 OUT 3 GND 2IN 1EN
Pin Description
Pin Number Pin Number Pin Name Pin Function
MIC39300 MIC39301
1 EN Enable (Input): TTL/CMOS compatible input. Logic high = enable; logic low
or open = shutdown.
1 2 IN Unregulated Input: +16V maximum supply.
2, TAB 3, TAB GND Ground: Ground pin and TAB are internally connected.
3 4 OUT Regulator Output
5 FLG Error Flag (Ouput): Open-collector indicates an output fault condition.
Active low.
MIC39300/39301 2 March 2000
Page 3
MIC39300/39301 Micrel
Absolute Maximum Ratings (Note 1)
Supply Voltage (VIN) ..................................... –20V to +20V
Enable Voltage (VEN) ..................................................+20V
Storage Temperature (TS) ....................... –65°C to +150°C
Lead Temperature (soldering, 5 sec.) ....................... 260°C
ESD, Note 3
Operating Ratings (Note 2)
Supply Voltage (VIN) .................................. +2.25V to +16V
Enable Voltage (VEN) ..................................................+16V
Maximum Power Dissipation (P
Junction Temperature (TJ) ....................... –40°C to +125°C
Package Thermal Resistance
)..................... Note 4
D(max)
TO-263 (θJC) .........................................................2°C/W
TO-220 (θJC) .........................................................2°C/W
Electrical Characteristics
TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted Symbol Parameter Condition Min Typ Max Units
V
OUT
∆V
/∆T Output Voltage Temp. Coefficient, 20 100 ppm/°C
OUT
V
DO
I
GND
I
GND(do)
I
OUT(lim)
Enable Input (MIC39301)
V
EN
I
IN
I
OUT(shdn)
Flag Output (MIC39301)
I
FLG(leak)
V
FLG(do)
V
FLG
Output Voltage 10mA –1 1 %
10mA ≤ I
Line Regulation I
= 10mA, V
OUT
Load Regulation VIN = V
≤ 3A, V
OUT
OUT
+ 1V, 10mA ≤ I
OUT
+ 1V ≤ VIN ≤ 8V –2 2 %
OUT
+ 1V ≤ VIN ≤ 8V 0.06 0.5 %
≤ 3A 0.2 1 %
OUT
Note 5
Dropout Voltage, Note 6 I
Ground Current, Note 7 I
Dropout Ground Pin Current VIN ≤ V Current Limit V
= 100mA, ∆V
OUT
I
= 750mA, ∆V
OUT
I
= 1.5A, ∆V
OUT
I
= 3A, ∆V
OUT
= 750mA, VIN = V
OUT
I
= 1.5A, VIN = V
OUT
I
= 3A, VIN = V
OUT
OUT(nominal)
= 0V, VIN = V
OUT
= –1% 80 200 mV
OUT
= –1% 200 mV
OUT
= –1% 320 mV
OUT
= –1% 400 500 mV
OUT
+ 1V 10 20 mA
OUT
+ 1V 17 mA
OUT
+ 1V 45 mA
OUT
– 0.5V, I
+ 1V 4.5 A
OUT
= 10mA 6 mA
OUT
Enable Input Voltage logic low (off) 0.8 V
logic high (on) 2.25 V
Enable Input Current VEN = V
IN
15 30 µA
75 µA
V
= 0.8V 2 µA
EN
4 µA
Shutdown Output Current Note 8 10 20 µA
Output Leakage Current VOH = 16V 0.01 1 µA
2 µA
Output Low Voltage VIN = 2.250V, IOL, = 250µA, Note 9 220 300 mV
400 mV
Low Threshold % of V
OUT
93 % High Threshold 99.2 % Hysteresis 1%
March 2000 3 MIC39300/39301
Page 4
MIC39300/39301 Micrel
Note 1. Exceeding the absolute maximum ratings may damage the device. Note 2. The device is not guaranteed to function outside its operating rating. Note 3. Devices are ESD sensitive. Handling precautions recommended. Note 4. P Note 5. Output voltage temperature coefficient is ∆V Note 6. VDO = VIN – V Note 7. I Note 8. VEN ≤ 0.8V, VIN ≤ 8V, and V Note 9. For a 2.5V device, VIN = 2.250V (device is in dropout).
= (T
D(max)
is the quiescent current. IIN = I
GND
– TA) ÷ θJA, where θJA depends upon the printed circuit layout. See “Applications Information.”
J(max)
when V
OUT
decreases to 99% of its nominal output voltage with VIN = V
OUT
GND
= 0V
OUT
OUT(worst case)
+ I
OUT
.
÷ (T
J(max)
– T
J(min)
) where T
is +125°C and T
J(max)
+ 1V.
OUT
J(min)
is 0°C.
MIC39300/39301 4 March 2000
Page 5
MIC39300/39301 Micrel
0
50
100
150
200
250
300
350
400
0 1000 2000 3000
DROPOUT VOLTAGE (mV)
OUTPUT CURRENT (mA)
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
1.2 1.6 2.0 2.4 2.8 3.2 3.6
OUTPUT VOLTAGE (V)
INPUT VOLTAGE (V)
0
10
20
30
40
50
0 1000 2000 3000
GROUND CURRENT (mA)
OUTPUT CURRENT (mA)
0
10
20
30
40
50
60
70
80
90
100
024681012
GROUND CURRENT (mA)
SUPPLY VOLTAGE (V)
0
1
2
3
4
5
6
7
8
-40 -20 0 20 40 60 80 100120
GROUND CURRENT (mA)
TEMPERATURE (°C)
0
1
2
3
4
5
6
-40 -20 0 20 40 60 80 100120
SHORT CIRCUIT CURRENT (A)
TEMPERATURE (°C)
Typical Characteristics
Power Supply
vs. Ripple Rejection
50
40
30
V
= 2.5V
OUT
20
PSRR (dB)
= 3.3V
V
IN
= 47µF
C
OUT
10
I
= 3A
LOAD
0
1x1011x1021x1031x1041x1051x10
FREQUENCY (Hz)
Dropout Voltage
600
500
400
300
200
100
DROPOUT VOLTAGE (mV)
vs. Temperature
V
= 2.5V
OUT
= 3A
I
LOAD
0
-40 -20 0 20 40 60 80 100120
TEMPERATURE (°C)
Power Supply
vs. Ripple Rejection
50
Dropout Voltage
vs. Output Current
40
30
V
= 2.5V
OUT
20
PSRR (dB)
= 3.3V
V
IN
C
= 100µF
OUT
10
= 3A
I
LOAD
6
0
1x1011x1021x1031x1041x1051x10
FREQUENCY (Hz)
6
Ground Current
Dropout Characteristics
I
= 100mA
LOAD
I
= 3A
LOAD
I
= 1.5A
LOAD
vs. Output Current
V
OUT
I
LOAD
= 2.5V = 3A
10
8
6
4
2
GROUND CURRENT (mA)
0
024681012
25
20
15
March 2000 5 MIC39300/39301
10
5
GROUND CURRENT (mA)
0
-40 -20 0 20 40 60 80 100120
Ground Current
vs. Supply Voltage
I
= 100mA
LOAD
I
= 10mA
LOAD
SUPPLY VOLTAGE (V)
Ground Current vs. Temperature
V
= 2.5V
OUT
= 1.5A
I
LOAD
TEMPERATURE (°C)
Ground Current
vs. Supply Voltage
I
= 3000mA
LOAD
I
= 1500mA
LOAD
I
=
LOAD
1000mA
Ground Current
vs. Temperature
60
50
40
30
20
10
GROUND CURRENT (mA)
0
-40 -20 0 20 40 60 80 100120
TEMPERATURE (°C)
V I
LOAD
OUT
= 2.5V = 3A
Ground Current
vs. Temperature
V
= 2.5V
OUT
= 100mA
I
LOAD
Short Circuit vs.
Temperature
VIN = 3.5V (typical 2.5V device)
Page 6
MIC39300/39301 Micrel
y
Output Voltage vs.
2.60
2.58
2.56
2.54
2.52
2.50
2.48
2.46
2.44
OUTPUT VOLTAGE (V)
2.42
2.40
-40 -20 0 20 40 60 80 100120
Temperature
I
= 10mA
LOAD
pical 2.5V device)
(t
TEMPERATURE (°C)
Flag-Low Voltage
250
200
150
100
FLAG VOLTAGE (mV)
vs. Temperature
FLAG-LOW
VOLTAGE
VIN = 2.25V
= 22kΩ
R
PULL-UP
50
0
-40 -20 0 20 40 60 80 100120140
TEMPERATURE (°C)
Error Flag
Pull-Up Resistor
6
5
FLAG HIGH
4
3
2
FLAG VOLTAGE (V)
1
0
0.01 0.1 1 10 100 100010000
(OK)
RESISTANCE (kΩ)
VIN = 5V
FLAG LOW
(FAULT)
(50mV/div.)
Output Voltage
Enable Current
vs. Temperature
12
10
8
6
4
2
ENABLE CURRENT µA)
0
-40 -20 0 20 40 60 80 100120140
VIN = V V
EN
TEMPERATURE (°C)
Line Transient
Response
V
= 2.5V
OUT
= 10mA
I
L
= 47µF
C
OUT
OUT
= 2.4V
+ 1V
(200mV/div.)
Output Voltage
(1A/div.)
Load Current
Load Transient
Response
3A
TIME (500µs/div.)
VIN = 3.3V
= 2.5V
V
OUT
= 47µF
C
OUT
10mA
(2V/div.)
Input Voltage
(100mV/div.)
Output Voltage
(1A/div.)
Load Current
3.3V
5V
TIME (100µs/div.)
Load Transient
Response
3A
TIME (500µs/div.)
VIN = 3.3V
= 2.5V
V
OUT
= 100µF
C
OUT
100mA
MIC39300/39301 6 March 2000
Page 7
MIC39300/39301 Micrel
Ref.
18V
O.V. I
LIMIT
Thermal
Shut­down
1.240V1.180V
EN*
IN
FLAG*
GND
OUT
* MIC39301 only
Functional Diagram
March 2000 7 MIC39300/39301
Page 8
MIC39300/39301 Micrel
Applications Information
The MIC39300/1 is a high-performance low-dropout voltage regulator suitable for moderate to high-current voltage regu­lator applications. Its 500mV dropout voltage at full load makes it especially valuable in battery-powered systems and as a high-efficiency noise filter in post-regulator applications. Unlike older NPN-pass transistor designs, where the mini­mum dropout voltage is limited by the base-to-emitter voltage drop and collector-to-emitter saturation voltage, dropout per­formance of the PNP output of these devices is limited only by the low VCE saturation voltage.
A trade-off for the low dropout voltage is a varying base drive requirement. Micrel’s Super βeta PNP™ process reduces this drive requirement to only 2% to 5% of the load current.
The MIC39300/1 regulator is fully protected from damage due to fault conditions. Current limiting is provided. This limiting is linear; output current during overload conditions is constant. Thermal shutdown disables the device when the die temperature exceeds the maximum safe operating tem­perature. Transient protection allows device (and load) sur­vival even when the input voltage spikes above and below nominal. The output structure of these regulators allows voltages in excess of the desired output voltage to be applied without reverse current flow.
MIC39300-x.x
V
IN
IN OUT
C
IN
GND
Figure 1. Capacitor Requirements
Thermal Design
Linear regulators are simple to use. The most complicated design parameters to consider are thermal characteristics. Thermal design requires four application-specific param­eters:
• Maximum ambient temperature (TA)
• Output Current (I
• Output Voltage (V
OUT
OUT
)
• Input Voltage (VIN)
• Ground Current (I
GND
Calculate the power dissipation of the regulator from these numbers and the device parameters from this datasheet, where the ground current is taken from the data sheet.
PD = (V
IN
– V
OUT
) I
OUT
The heat sink thermal resistance is determined by:
TT
θθθ
=
SA
where T
J (max)
−
J(max) A
P
D
−+
()
JC CS
≤ 125°C and θCS is between 0° and 2°C/W.
)
)
+ VIN·I
V
OUT
C
OUT
GND
resistor to drop excessive voltage and distribute the heat between this resistor and the regulator. The low dropout properties of Micrel Super βeta PNP regulators allow signifi­cant reductions in regulator power dissipation and the asso­ciated heat sink without compromising performance. When this technique is employed, a capacitor of at least 1.0µF is needed directly between the input and regulator ground.
Refer to
Application Note 9
for further details and examples
on thermal design and heat sink specification.
Output Capacitor
The MIC39300/1 requires an output capacitor to maintain stability and improve transient response. Proper capacitor selection is important to ensure proper operation. The MIC39300/1 output capacitor selection is dependent upon the ESR (equivalent series resistance) of the output capacitor to maintain stability. When the output capacitor is 47µF or greater, the output capacitor should have less than 1Ω of ESR. This will improve transient response as well as promote stability. Ultralow ESR capacitors, such as ceramic chip capacitors may promote instability. These very low ESR levels may cause an oscillation and/or underdamped tran­sient response. A low-ESR solid tantalum capacitor works extremely well and provides good transient response and stability over temperature. Aluminum electrolytics can also be used, as long as the ESR of the capacitor is < 1Ω.
The value of the output capacitor can be increased without limit. Higher capacitance values help to improve transient response and ripple rejection and reduce output noise.
Input Capacitor
An input capacitor of 1µF or greater is recommended when the device is more than 4 inches away from the bulk ac supply capacitance, or when the supply is a battery. Small, surface­mount, ceramic chip capacitors can be used for the bypass­ing. Larger values will help to improve ripple rejection by bypassing the input to the regulator, further improving the integrity of the output voltage.
Transient Response and 3.3V to 2.5V Conversion
By virtue of its low-dropout voltage, this device does not saturate into dropout as readily as similar NPN-based de­signs. When converting from 3.3V to 2.5V, the NPN-based regulators are already operating in dropout, with typical dropout requirements of 1.2V or greater. To convert down to
2.5V without operating in dropout, NPN-based regulators require an input voltage of 3.7V at the very least. The MIC39300/1 regulator will provide excellent performance with an input as low as 3.0V. This gives the PNP-based regulators a distinct advantage over older, NPN-based linear regulators.
MIC39300/39301 8 March 2000
Page 9
MIC39300/39301 Micrel
Minimum Load Current
The MIC39300/1 regulator is specified between finite loads. If the output current is too small, leakage currents dominate and the output voltage rises. A 10mA minimum load current is necessary for proper regulation.
Error Flag
The MIC39301 version features an error flag circuit which monitors the output voltage and signals an error condition when the voltage drops 5% below the nominal output voltage. The error flag is an open-collector output that can sink 10mA during a fault condition.
Low output voltage can be caused by a number of problems, including an overcurrent fault (device in current limit) or low input voltage. The flag is inoperative during overtemperature shutdown.
Enable Input
The MIC39301 version features an enable input for on/off control of the device. Its shutdown state draws “zero” current (only microamperes of leakage). The enable input is TTL/ CMOS compatible for simple logic interface, but can be connected to up to 20V. When enabled, it draws approxi­mately 15µA.
March 2000 9 MIC39300/39301
Page 10
MIC39300/39301 Micrel
Package Information
0.151 D ±0.005
0.108 ±0.005 (2.74 ±0.13)
0.818 ±0.005 (20.78 ±0.13)
(3.84 D ±0.13)
0.410 ±0.010
(10.41 ±0.25)
0.356 ±0.005 (9.04 ±0.13)
0.176 ±0.005 (4.47 ±0.13)
0.590 ±0.005 (14.99 ±0.13)
0.050 ±0.005 (1.27 ±0.13)
7°
0.050 ±0.003 (1.27 ±.08)
0.100 ±0.005 (2.54 ±0.13)
0.108 ±0.005 (2.74 ±0.13)
0.400 ±0.015
(10.16 ±0.38)
1.140 ±0.010 (28.96 ±0.25)
0.030 ±0.003 (0.76 ±0.08)
3-Lead TO-220 (T)
0.150 D ±0.005 (3.81 D ±0.13)
0.241 ±0.017 (6.12 ±0.43)
0.578 ±0.018
(14.68 ±0.46)
0.018 ±0.008
(0.46 ±0.020)
7°
3°
0.100 ±0.020
DIMENSIONS:
0.177 ±0.008 (4.50 ±0.20)
0.050 ±0.005 (1.27 ±0.13)
SEATING PLANE
(2.54 ±0.51)
INCH (MM)
7°
Typ.
0.550 ±0.010 (13.97 ±0.25)
0.067 ±0.005
(1.70 ±0.127)
0.268 REF (6.81 REF)
0.032 ±0.005 (0.81 ±0.13)
0.018 ±0.008 (0.46 ±0.20)
Dimensions:
0.103 ±0.013 (2.62±0.33)
inch
(mm)
5-Lead TO-220-5 (T)
MIC39300/39301 10 March 2000
Page 11
MIC39300/39301 Micrel
0.405±0.005
0.065±0.010 20°±2°
0.100 BSC 0.050
DIM. = INCH
0.405±0.005
0.065±0.010 20°±2°
0.050±0.005
0.360±0.005
0.600±0.025
0.015 ±0.002
3-Lead TO-263 (U)
0.050±0.005
0.360±0.005
8° MAX
0.176±0.005
0.050±0.005
SEATING PLANE
+0.004
0.004
–0.008
0.100±0.01
0.176±0.005
0.060±0.005
0.600±0.025
0.067±0.005 0.032 ±0.003
DIM. = INCH
5-Lead TO-263-5 (U)
8° MAX
0.015 ±0.002
SEATING PLANE
+0.004
0.004
–0.008
0.100±0.01
March 2000 11 MIC39300/39301
Page 12
MIC39300/39301 Micrel
MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB http://www.micrel.com
This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or
other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc.
© 2000 Micrel Incorporated
MIC39300/39301 12 March 2000
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