Page 1
MIC4575 Micrel
MIC4575
200kHz Simple 1A Buck Voltage Regulator
General Description
The MIC4575 is a series of easy to use fixed and adjustable
BiCMOS step-down (buck) switch-mode voltage regulators.
The 200kHz MIC4575 duplicates the pinout and function of
the 52kHz LM2575. The higher switching frequency may
allow up to a 2:1 reduction in output filter inductor size.
The MIC4575 is available in 3.3V, and 5V fixed output
versions or a 1.23V to 20V adjustable output version. Both
versions are capable of driving a 1A load with excellent line
and load regulation.
The feedback voltage is guaranteed to ±2% tolerance for
adjustable versions, and the output voltage is guaranteed to
±3% for fixed versions, within specified voltages and load
conditions. The oscillator frequency is guaranteed to ±10%.
In shutdown mode, the regulator draws less than 200µA
standby current. The regulator performs cycle-by-cycle
current limiting and thermal shutdown for protection under
fault conditions.
This series of simple switch-mode regulators requires a
minimum number of external components and can operate
using a standard series of inductors. Frequency compensation is provided internally.
The MIC4575 is available in TO-220 (T) and TO-263 (U)
packages for the industrial temperature range.
Features
• Fixed 200kHz operation
• 3.3V, 5V, and adjustable output versions
• Voltage over specified line and load conditions:
Fixed version: ±3% max. output voltage
Adjustable version: ±2% max. feedback voltage
• Guaranteed 1A switch current
• Wide 4V to 24V input voltage range
• Wide 1.23V to 20V output voltage range
• Requires minimum external components
• < 200µA typical shutdown mode
• 75% efficiency (adjustable version > 75% typical)
• Standard inductors and capacitors are
25% of typical LM2575 values.
• Thermal shutdown
• Overcurrent protection
• 100% electrical thermal limit burn-in
Applications
• Simple high-efficiency step-down (buck) regulator
• Efficient preregulator for linear regulators
• On-card switching regulators
• Positive-to-negative converter (inverting buck-boost)
• Battery Charger
• Negative boost converter
• Step-down 6V to 3.3V for Intel Pentium™
and similar microprocessors
Typical Applications
Shutdown
Enable
6V to 24V
22µF
C1
35V
Shutdown
Enable
8V to 24V
C1
150µF
35V
5
1
V
IN
SHDN
MIC4575-5.0BT
1
V
IN
MIC4575BU
GND
3
25
SW
4
FB
GND
3
D1
1N5819
Fixed Regulator
L1
68µH
D1
MBRS130LT3
SWSHDN
FB
2
4
Adjustable Regulator
L1
68µH
R2
2.37k
1%
R1
1.24k
1%
5.0V/1A
C2
330µF
16V
C3
3300pF
3.6V/1A
C2
330µF
6.3V
4-106 April 1998•
Page 2
MIC4575 Micrel
Ordering Information
Part Number Voltage Temperature Range Package
MIC4575-3.3BT 3.3V –40°C to +85°C 5-lead TO-220
MIC4575-5.0BT 5.0V –40°C to +85°C 5-lead TO-220
MIC4575BT Adjustable –40°C to +85°C 5-lead TO-220
MIC4575-3.3BU 3.3V –40°C to +85°C 5-lead TO-263
MIC4575-5.0BU 5.0V –40°C to +85°C 5-lead TO-263
MIC4575BU Adjustable –40°C to +85°C 5-lead TO-263
Pin Configuration
5 SHDN
4FB
TAB
3 GND
2SW
1V
IN
TAB
Pin Description
Pin Number Pin Name Pin Function
1V
2 SW Switch (Output): Emitter of NPN output switch. Connect to external storage
3, TAB GND Ground
4 FB Feedback (Input): Output voltage feedback to regulator. Connect to output
5 SHDN Shutdown (Input): Logic low enables regulator. Logic high (> 2.4V) shuts
IN
5-Lead TO-220 (T)
5 SHDN
4FB
3 GND
2SW
1V
IN
5-Lead TO-263 (U)
Supply Voltage (Input): Unregulated +4V to +40V supply voltage.
inductor and Shottky diode.
of supply for fixed versions. Connect to 1.23V tap of resistive divider for
adjustable versions.
down regulator.
4
April 1998• 4-107
Page 3
MIC4575 Micrel
Absolute Maximum Ratings
Supply Voltage (VIN) Note 1 .......................................+40V
Shutdown Voltage (V
Output Switch (VSW) steady state.................................–1V
Storage Temperature (TS) ......................... –65°C to 150°C
) .......................... –0.3V to +36V
SHDN
Operating Ratings
Supply Voltage (VIN) ...................................................+24V
Junction Temperature ............................................. +150°C
Package Thermal Resistance
TO-220, TO-263 (θJA) .........................................65°C/W
TO-220, TO-263 (θJA) ...........................................2°C/W
Electrical Characteristics
VIN = 12V; I
Parameter Condition Min Typ Max Units
MIC4575 [Adjustable]
Feedback Voltage 1.217 1.230 1.243 V
Feedback Voltage 8V ≤ V
Efficiency I
Feedback Bias Current 50 100 nA
MIC4575-3.3
Output Voltage 3.234 3.3 3.366 V
Output Voltage 6V ≤ V
Efficiency I
MIC4575-5.0
Output Voltage 4.900 5.0 5.100 V
Output Voltage 8V ≤ V
Efficiency I
MIC4575 / -3.3 / -5.0
Oscillator Frequency 180 200 220 kHz
Saturation Voltage I
Maximum Duty Cycle (On) FB connected to 0V 90 95 %
Current Limit Peak Current, t
Output Leakage Current V
Quiescent Current 510mA
Standby Quiescent Current SHDN = 5V (regulator off) 50 200 µA
SHDN Input Logic Level V
SHDN Input Current SHDN = 5V (regulator off) 4 30 µA
= 200mA; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +85°C; unless noted.
LOAD
≤ 24V, 0.2A ≤ I
IN
= 1A, V
LOAD
≤ 24V, 0.2A ≤ I
IN
= 1A 72 %
LOAD
≤ 24V, 0.2A ≤ I
IN
= 1A 77 %
LOAD
= 1A 1 1.3 V
OUT
= 24V, FB connected to 0V
IN
Output = 0V 0 2 mA
= 5V 77 %
OUT
≤ 3µs 1.7 2.2 3.0 A
ON
≤ 1A 1.193 1.230 1.267 V
LOAD
≤ 1A 3.168 3.3 3.432 V
LOAD
≤ 1A 4.800 5.0 5.200 V
LOAD
Output = –1V 7.5 30 mA
= 0V (regulator off) 2.2 1.4 V
OUT
= 3.3 or 5V (regulator on) 1.2 1.0 V
V
OUT
SHDN = 0V (regulator on) –10 0.01 10 µA
1.180 1.280 V
500 nA
3.135 3.465 V
4.750 5.250 V
1.5 V
1.3 3.2 A
2.4 V
0.8 V
General Note: Devices are ESD protected, however, handling precautions are recommended.
Note 1: The MIC4575 is not guaranteed to survive a short circuit to ground for input voltage above 24V.
4-108 April 1998•
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MIC4575 Micrel
Block Diagrams
+24V max.
V
Shutdown
Enable
SHDN
Internal
Regulator
200kHz
Oscillator
Thermal
Shutdown
Current
Limit
IN
C
IN
Shutdown
Enable
SHDN
Driver
1.23V
Bandgap
R1
R2
GND
1A
Switch
MIC4575-x.x
Com-
parator
Error
Amp.
Block Diagram with External Components
Fixed Step-Down Regulator
+24V max.
V
IN
Internal
Regulator
200kHz
Oscillator
MIC4575
Com-
parator
[Adjustable]
Thermal
Shutdown
Error
Amp.
Driver
1.23V
Bandgap
Current
Limit
GND
1A
Switch
SW
FB
SW
FB
L1
D1
C
IN
V
OUT VREF
R1 R2
L1
D1
R1
R2
V
OUT
C
OUT
4
R1
+ 1
R2
V
OUT
1
V
REF
V
OUT
C
OUT
Block Diagram with External Components
Adjustable Step-Down Regulator
April 1998• 4-109
Page 5
MIC4575 Micrel
Functional Description
The MIC4575 is a variable duty cycle switch-mode regulator
with an internal power switch. Refer to the block diagrams.
Supply Voltage
The MIC4575 operates from a +4V to +24V unregulated
input. Highest efficiency operation is from a supply voltage
around +15V.
Enable/Shutdown
The shutdown (SHDN) input is TTL compatible. Ground the
input if unused. A logic-low enables the regulator. A logichigh shuts down the internal regulator which reduces the
current to typically 50µA.
Feedback
Fixed versions of the regulator have an internal resistive
divider from the feedback (FB) pin. Connect FB directly to the
output line.
Adjustable versions require an external resistive voltage
divider from the output voltage to ground, connected from the
1.23V tap to FB.
Duty Cycle Control
A fixed-gain error amplifier compares the feedback signal
with a 1.23V bandgap voltage reference. The resulting error
amplifier output voltage is compared to a 200kHz sawtooth
waveform to produce a voltage controlled variable duty cycle
output.
A higher feedback voltage increases the error amplifier
output voltage. A higher error amplifier voltage (comparator
inverting input) causes the comparator to detect only the
peaks of the sawtooth, reducing the duty cycle of the comparator output. A lower feedback voltage increases the duty
cycle.
Output Switching
When the internal switch is on, an increasing current flows
from the supply V
output capacitor C
through external storage inductor L1, to
IN,
and the load. Energy is stored in the
OUT
inductor as the current increases with time.
When the internal switch is turned off, the collapse of the
magnetic field in L1 forces current to flow through fast
recovery diode D1, charging C
OUT
.
Output Capacitor
External output capacitor C
provides stabilization and
OUT
reduces ripple.
Return Paths
During the on portion of the cycle, the output capacitor and
load currents return to the supply ground. During the off
portion of the cycle, current is being supplied to the output
capacitor and load by storage inductor L1, which means that
D1 is part of the high-current return path.
Applications Information
The applications circuits that follow have been constructed
and tested. Refer to Application Note 15 for additional
information, including efficiency graphs and manufacturer’s
addresses and telephone numbers for most circuits.
L1
C1
3.3V/1A
C2
330µF
16V
5
SHDN
1
V
IN
MIC4575BT
GND
3
25
GND
SW
FB
3
68µH
4
D1
1N5819
SHDN
6V to 24V
C1
150µF
35V
MIC4575-3.3BT
1
V
IN
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
L1 Sumida RCH106-680K, DCR = 0.22Ω
L1 Bi HM77-11003, DCR = 0.233Ω, Note 2
Figure 1. 6V–24V to 3.3V/1A Buck Converter
Through Hole
16V to 24V
68µF
63V
For a mathematical approach to component selection and
circuit design, refer to Application Note 14.
L1
25
GND
SW
4
FB
3
SHDN
8V to 24V
C1
150µF
35V
MIC4575-5.0BT
1
V
IN
C1 Nichicon UPL1J151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
L1 Sumida RCH106-680K, DCR = 0.22Ω
L2 Bi HM77-11003, DCR = 0.233Ω, Note 2
68µH
D1
1N5819
5.0V/1A
Figure 2. 8V–24V to 5V/1A Buck Converter
Through Hole
SW
FB
2
4
L1
150µH
MBR160
R2
13.0k
1%
R1
1.50k
1%
12V/1A
C2
330µF
16V
C2
330µF
16V
Note 2: Surfacemount component.
C1 Nichicon UPL1J680MPH, ESR = 0.17Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola MBR160
L1 Sumida RCH110-151K, DCR = 0.23Ω
Figure 3. 16V–24V to 12V/1A Buck Converter, Through Hole
4-110 April 1998•
Page 6
MIC4575 Micrel
C1
150µF
35V
D1
MBRS130LT3
C2
470µF
16V
L1
68µH
GND
FB
SW
MIC4575-3.3BU
SHDN
6V to 24V
3.3V/1A
V
IN
C1 Sanyo 35CV150GX, ESR = 0.17Ω
C2 Sanyo 16CV470GX, ESR = 0.17Ω
D1 Motorola MBRS130LT3
L1 Coilcraft DO3316P-683, DCR = 0.16Ω
L1 Bi HM77-11003, DCR = 0.233Ω
3
4
25
1
C1
150µF
35V
D1
MBRS130LT3
C2
470µF
16V
L1
68µH
GND
FB
SW
MIC4575-5.0BU
SHDN
8V to 24V
5V/1A
V
IN
C1 Sanyo 35CV150GX, ESR = 0.17Ω
C2 Sanyo 16CV470GX, ESR = 0.17Ω
D1 Motorola MBRS130LT3
L1 Coilcraft DO3316P-683, DCR = 0.16Ω
L1 Bi HM77-11003, DCR = 0.233Ω
3
4
25
1
C1
150µF
35V
GND
FB
SW
MIC4575-5.0BT
SHDN
8V to 18V
V
IN
C1 Nichicon UPL1V151MPH
ESR = 0.13Ω
C2 Nichicon UPL1C681MPH
ESR = 0.065Ω
D1 Motorola 1N5819
L1 Coiltronics PL52A-10-500
DCR = 0.045Ω
1
5
4
2
3
1N5819
D1
C2
680µF
16V
-5V/0.2A
L1
10µH
L1
2
SWSHDN
FB
68µH
4
D1
R2
2.49k
1%
R1
1.50k
1%
6V to 24V
C1
22µF
35V
5
1
V
MIC4575BU
IN
GND
3
MBRS130LT3
C1 AVX TPSE226M035R0300, ESR = 0.3Ω
C2 AVX TPSE337M006R0100, ESR = 0.1Ω
D1 Motorola MBRS130LT3
L1 Coiltronics CTX68-4P, DCR = 0.238Ω
Figure 4. 6V–24V to 3.3V/1A Buck Converter
Low-Profile Surface Mount
L1
2
SWSHDN
FB
68µH
4
D1
R2
3.01k
1%
R1
1.00k
1%
8V to 24V
C1
22µF
35V
5
1
V
MIC4575BU
IN
GND
3
MBRS130LT3
C1 AVX TPSE226M035R0300, ESR = 0.3Ω
C2 AVX TPSE227M010R0100, ESR = 0.1Ω
D1 Motorola MBRS130LT3
L1 Coiltronics CTX68-4P, DCR = 0.238Ω
Figure 5. 8V–24V to 5V/1A Buck Converter
Low-Profile Surface Mount
L1
2
SWSHDN
FB
150µH
4
D1
SS26
R2
13.0k
1%
R1
1.50k
1%
16V to 24V
C1
10µF
50V
5
1
V
MIC4575BU
IN
GND
3
C3
3300pF
C3
3300pF
C3
3300pF
3.3V/1A
C2
330µF
6.3V
5V/1A
C2
220µF
10V
12V/1A
C2
68µF
20V
Figure 7. 6V–24V to 3.3V/1A Buck Converter
Lower-Cost Surface Mount
Figure 8. 8V–24V to 5V/1A Buck Converter
Lower-Cost Surface Mount
L1
2
150µH
4
SS26
R2
13.0k
1%
R1
1.50k
1%
16V to 24V
C1
47µF
50V
X2
5
1
SHDN
V
MIC4575BU
IN
GND
3
SW
FB
12V/1A
C2
470µF
16V
4
C1 Tokin C55YU1H106Z
C2 AVX TPSE686M020R0150, ESR = 0.15Ω
D1 General Instruments SS26
L1 Coiltronics CTX150-4, DCR = 0.372Ω
Figure 6. 16V–24V to 12V/1A Buck Converter
April 1998• 4-111
Low-Profile Surface Mount
Figure 10. 8V–18V to –5V/0.2A Buck-Boost Converter
Through Hole
C1 Nichicon UUX1H470MT1GS, ESR = 0.4Ω
C2 Sanyo 16CV470GX, ESR = 0.17Ω
D1 General Instruments SS26
L1 Coiltcraft DO5022P-154, DCR = 0.218Ω
Figure 9. 16V–24V to 12V/1A Buck Converter
Lower-Cost Surface Mount
Page 7
MIC4575 Micrel
4.75V to 5.25V
C1
150µF
35V
1
V
IN
MIC4575BT
5
SHDN
GND
3
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C681MPH, ESR = 0.065Ω
D1 Motorola 1N5819
L1 Coiltronics PL52A-15-500, DCR = 0.054Ω
Figure 11. 5V to –5V/0.3A Buck-Boost Converter
25
GND
SW
4
FB
3
IN
8V to 18V
C1
22µF
35V
MIC4575BU
1
V
IN
C1 AVX TPSE226M035R0300, ESR = 0.3Ω
C2 AVX TPSE227M010R0100, ESR = 0.1Ω
C4 AVX TPSE227M010R0100, ESR = 0.1Ω
D1 Motorola MBRS130LT3
T1 Coiltronics CTX68-4P, DCR = 0.238Ω
L1 Coilcraft DO1608C-102
V
SHDN
2
SW
R2
1%
C4
1000pF
R1
3.01k
1%
R3
10K
FB
4
1.00K
Through Hole
T1
68µH
12
D1
MBRS130LT3
L1
34
1µH
C4
220µF
10V
R4
5.1K
C3
0.01µF
D1
1N5819
R2
3.01k
1%
R1
1.00K
1%
L1
15µH
C2
680µF
16V
C3
3300pF
-5V/0.3A
5V/1A
5mV
V
OUT
C2
220µF
10V
P-P
Figure 12. Low Output-Noise Regulator (5mV Output Ripple )
25
GND
3
MBRS130LT3
SW
FB
4
D1
C5
220µF
10V
1
SHDN
V
MIC4575BU
IN
V
IN
8V to 18V
C1
22µF
35V
C1 AVX TPSE226M035R0300, ESR = 0.3Ω
C2 AVX TPSE227M010R0100, ESR = 0.1Ω
C4 AVX TPSE227M010R0100, ESR = 0.1Ω
C5 AVX TPSE227M010R0100, ESR = 0.1Ω
D1 Motorola MBRS130LT3
D2 Motorola MBRS130LT3
T1 Coiltronics CTX68-4P, DCR = 0.238Ω
Figure 13. Split ±5V Supply
T1
68µH
21
R2
3.01k
1%
R1
1.00K
1%
4
L1
MBRS130LT3
3
+I
+ I
OUT
+V
DC
DC 40% then I
40% then I
DC
V
OUT
OUT
IN
1A
0.5V
0.5V
OUT+IOUT
OUTIOUT
D2
C3
3300pF
/+I
+V
OUT
OUT
5V/0.5A
C2
220µF
10V
C4
220µF
10V
-V
/-I
OUT
OUT
-5V/0.5A
at V
≥15V
IN
Load Regulation≈±5%
(1 DC)
4-112 April 1998•
Page 8
MIC4575 Micrel
Q1
2N4339
R3
3.3K
V
IN
4V to 24V
C1
150µF
35V
1
SHDN
V
MIC4575BT
IN
GND
SW
FB
3
68µH
4
D1
1N5819
L1
25
R1
200K
R2
15k
U2
LM4041CIZ-1.2 V
(0-12V)/0.5A
V
OUT
R4
C2
330Ω
330µF
0.5W
16V
OUT
Min = 60mV
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
L1 Coiltronics PL52B-68-500, DCR = 0.095Ω
U2 Micrel LM4041CIZ-1.2
Figure 14. Adjustable (0V–12V) Output-Voltage Regulator
U1
25
GND
SW
4
FB
3
V
IN
4V to 15V
C1
150µF
35V
SHDN
MIC4575BT
1
V
IN
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
L1 Coiltronics PL52B-68-500, DCR = 0.095Ω
U2 National LM358
Figure 15. Low Output-Voltage Regulator (1V)
25
GND
SW
4
FB
3
R1
1
2.5V
SHDN
V
MIC4575BT
IN
V
IN
9V to 24V
C1
150µF
35V
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
L1 Coiltronics PL52B-68-500, DCR = 0.095Ω
U2 National LM358
Q1 Siliconix VN2222LL
R1 KRL SP-1/2-A1-0R250J
V
V
IN min
I
OUT
BATT
0.9
1.23VR5R2
D1
1N5819
L1
68µH
D1
1N5819
VN2222LL
L1
68µH
200Ω
C4
1000pF
1.00k
R2
1%
Q1
R5
1%
R4
V
V
IN min
OUT
0.9
1.5V
and
IN
min
3
2
U2
LM358
1.00k
V
R2
1%
V
1
R1
249Ω
1%
R1
U2
LM358
1
0.25Ω
R3
10K
3
2
OUT
C2
330µF
16V
2.5V
1N5819
C2
330µF
16V
D2
V
OUT
1V/1A
R3
1k
I
OUT
1A
6-8 Cells
4
V
BATT
C3
0.01µF
3k
DZ1
1N5244
14V
Figure 16. 1A Battery Charger (6–8 cells)
April 1998• 4-113
Page 9
MIC4575 Micrel
D3
25
GND
SW
4
FB
3
R7
1k
V
IN
8V to 24V
C1
150µF
35V
U1 Micrel MIC4575BT
U2 National LM358
U3 Micrel LM4041CIZ-1.2
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
D2 Motorola 1N5819
D3 Motorola 1N4148
L1 Coiltronics PL52B-68-500, DCR = 0.095Ω
R1 KRL SP-1-A1-0R100J
Q1 Siliconix VN2222LL
V
IN min VBATT
SHDN
MIC4575-BT
1
V
IN
/ 0.9 2.5V
Figure 17. 0.1A–1A Variable-Current Battery Charger
25
GND
SW
4
FB
3
R6
1k
V
IN
8V to 24V
C1
150µF
35V
1
SHDN
V
IN
MIC4575-BT
R6
3k
C4
1000pF
1N4148
1
0.01µF
D3
1N4148
R5
3k
C4
1000pF
D1
1N5819
C3
3
2
DZ1
1N5244
14V
1
L1
68µH
U2A
1/2LM358
D1
1N5819
R2
100Ω
1%
R4
1.21k
1%
L1
68µH
3
U2A
1/2LM358
2
R1
0.1Ω
R3
10k
7
Q1
VN2222LL
R2
100Ω
1%
R1
0.1Ω
R3
10k
V
IN
8
4
1N5819
C2
330µF
16V
U2B
1/2 LM358
5
6
D2
V
IN
C2
330µF
16V
R5
10k
VR1
10k
I
OUT
0.1A to 1A
2-8 Cells
D2
1N5819
V
BATT
U3
LM4041CIZ-1.2
I
OUT
1A
2-8 Cells
V
BATT
U1 Micrel MIC4575BT
U2 National LM358
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
D2 Motorola 1N5819
D3 Motorola 1N4148
L1 Coiltronics PL52B-68-500, DCR = 0.095Ω
R1 KRL SP-1-A1-0R100J
Q1 Siliconix VN2222LL
V
IN min VBATT
1.23VR4R2
I
OUT
/ 0.9 2.5V
R1
Figure 18. 1A Battery Charger (2–8 Cells)
C3
0.01µF
5
6
DZ1
1N5244
14V
V
IN
8
4
U2B
1/2 LM358
7
Q1
VN2222LL
R4
1.21k
1%
4-114 April 1998•
Page 10
MIC4575 Micrel
V
IN
8V to 24V
C1
68µF
63V
V
IN
6V to 18V
C1
22µF
35V
1
V
5
SD
U1
IN
MIC4575BT
2
V
SW
4
FB
L1
68µH
D1
MBR160
GND
3
C1 Nichicon UPL1J680MPH, ESR = 0.17Ω
C2 Nichicon UPL1J680MPH, ESR = 0.17Ω
C4 AVX TPSE227M010R0100, ESR = 0.1 Ω
D1 Motorola MBRS160
L1 Coiltronics PL52B-68-500, DCR = 0.095Ω
Figure 19. Remote-Sensing Regulator
Q1
D3
1N4148
Si9435
3
4
25
SHDN
SW
MIC4575BU
1
V
IN
GND
3
C1 AVX TPSE226M035R0300, ESR = 0.3Ω
C2 AVX TPSE686M020R0150, ESR = 0.15Ω
C3 AVX TPSE686M020R0150, ESR = 0.15Ω
C4 AVX TPSE686M020R0150, ESR = 0.15Ω
D1 Motorola MBRS130LT3
D2 Motorola MBRS130LT3
T1 Coiltronics CTX150-4, DCR = 0.372Ω
Q1 Siliconix Si 9435, PMOS
FB
4
T1
C2
68µF
63V
0.01µF
C2
68µF
C3
T1
150µH
D1
MBRS130LT3
D2
MBRS130LT3
R1
30Ω
R2
3.01k
1%
R3
1.00k
1%
R4
10Ω
12
10 ft Wire
0.5 Ω
+V
+V
SENSE
–V
SENSE
–V
R2
13.0k
1%
R1
1.50K
1%
R3
1k
C5
3300pF
C4
68µF
20V
V
OUT
5V/1A
C4
220µF
10V
V
OUT
12V/100mA
C3
68µF
20V
–V
OUT
–12V/100mA
(–11V to –12V)
4
V
IN
8V to 24V
C1
150µF
35V
Figure 20. 6V–18V to Split ±12V/100mA Supply
U1
25
GND
SW
FB
3
D1
1N5819
4
C3
0.1µF
1
SHDN
V
IN
MIC4575BU
R3
113k
V
IN
1%
C4
0.01µF
U2B
1/2 LM358
U1 Micrel MIC4575BT
U2 National LM358
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
D2 Motorola 1N5819
DZ1Motorola 1N5244
L1 Bi HM77-11003, DCR = 0.233Ω
R1 KRL SP-1/2-A1-0R100J
8
8
7
6
5
4
V
IN min
I
OUT
Figure 21. 1A Battery Charger
L1
68µH
R2
10k
1%
=
=
1.23V
R1
V
BATT
0.9
DZ1
1N5244
14V
10k
+ 2.5V
R2
R2
1N5819
C2
330µF
16V
0.1Ω
R4
R3
D2
R1
I
OUT
1A
V
BATT
2–8 Cells
April 1998• 4-115
Page 11
MIC4575 Micrel
V
OUT
V
OUTmin
0V–12V
R6
330Ω
0.5W
= 60mV
V
IN
4V to 24V
U1
25
SHDN
SW
MIC4575BT
C1
150µF
35V
1
V
IN
GND
3
4
FB
U2B
1/2LM358
R3
20k
1%
U1 Micrel MIC4575BT
U2 National LM358
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C2 Nichicon UPL1C102MPH, ESR = 0.047Ω
D1 Motorola 1N5819
L1 Bi HM77-11003, DCR = 0.233Ω
L1
68µH
D1
1N5819
V
IN
5
8
6
4
C4
0.01µF
7
C3
3300pF
U2A
2
1
3
1/2LM358
R1
20k
1%
R2
2k
1%
R6
220Ω
C2
1000µF
16V
R4
2k
1%
R5
10K
V
IN min
V
OUT max
V
OUT
=
0.9
+ 2.5V
= 1.23V 1
R1
R2
R1 = R3 and R2 = R4
Figure 22. Improved Adjustable Output-Voltage Regulator (0V–12V)
V
IN
8V to 24V
C1
150µF
35V
U1
25
SHDN
SW
MIC4575BT
1
V
IN
GND
3
U1 Micrel MIC4575BT
U2 National LM358
U3 Micrel MIC2506BM
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C1 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
D2 Motorola 1N5819
DZ1Motorala 1N5236
L1 Bi HM77-11003, DCR = 0.233Ω
Q1 Siliconix VN2222LL
R1 KRL SP-1/2-A1-0R100J
FB
4
R6
1k
U2B
1/2 LM358
R5
1000pF
5
6
1N4148
3k
C4
Figure 23. Switchable Battery-Pack Charger
D3
V
D1
1N5819
IN
8
7
4
1/2LM358
1
0.01µF
C5
0.01µF
U2A
C3
L1
68µH
DZ1
1N5236
7.5V
I
2
U4A
7404
OUT
1A
C2
330µF
16V
R8
100k
2
FLG A
3
FLG B
1
CTL A
4
CTL B
U3
7
IN
MIC2506
GND
6
OUT A
OUT B
510k
R9
8
R10
5
510k
Bat B
4 Cells
NiCad
Bat A
4 Cells
NiCad
R1
0.1Ω
R2
100Ω
1%
3
R3
2
10k
Q1
VN2222LL
R7
100k
Bat A
A/B
Bat B
1
R4
1.21k
1%
4-116 April 1998•
Page 12
MIC4575 Micrel
D3
I
4
OUT
1A
V
BATT
2 Li Cells
U1
GND
R5
R4
SW
FB
3
SHDN
V
IN
12V to 24V
C1
150µF
35V
U1 Micrel MIC4575BT
U2 National LM358
U3 National LM3420
U4 National LM339
C1 Nichicon UPL1V151MPH, ESR = 0.12Ω
C1 Nichicon UPL1C331MPH, ESR = 0.12Ω
D1 Motorola 1N5819
D2 Motorola 1N5819
DZ1Motorala 1N5244
L1 Bi HM77-11003, DCR = 0.233Ω
R1 KRL SP-1/2-A1-0R100J
Q1 Siliconix VN2222LL
1.24V
I
=
OUT
I
OUT
V
IN min
I
OUT
I
OUT
R3
=1.02A
V
BATT
>=
0.9
END 60mA
END 1.23V
R2
R1
1
V
IN
+ 2.5V
R2
R3
MIC4575BT
–
R1
25
4
R7
1k
U2B
1/2 LM358
END
R6
1000pF
5
6
V
3k
C4
IN
R8
10k
1N4148
V
IN
8
4
C6
0.1µF
1
D1
1N5819
C5
0.1µF
7
R9
10M
V
IN
3
12
L1
68µH
U2A
1/2LM358
1
C3
0.01µF
7
6
LM339
3
2
R10
10k
R2
100Ω
1%
R3
1.21k
1%
C7
0.01µF
R1
0.1Ω
1.0k
1%
Q1
VN2222LL
Q2
2N2222
R5
R4
13.0k
1%
C2
330µF
16V
C8
0.01µF
D2
1N5819
3
1
R12
100k
U3
COMP
LM3420
OUT
8
IN
GND
4
Figure 24. Lithium-Ion Battery Charger with End-of-Charge Flag
U1 U2
25
GND
SW
4
FB
3
D1
MBRS130LT3
SHDN
V
1
IN
MIC4575BU
V
IN
9V to 18V
C1
22µF
35V
U1 Micrel MIC4575BU
U2 Micrel MIC29150-5.0BU
C1 AVX TPSE226M035R0300, ESR = 0.3Ω
C2 AVX TPSE227M010R0100, ESR = 0.1Ω
C3 AVX TPSE106M010R0200, ESR = 0.2Ω
C4 Sprague 293D226X0010C2W
D1 Motorola MBRS130LT3
D2 Motorola MBRS130LT3
L1 Bi HM77-11003, DCR = 0.233Ω
L2 Coilcraft D016087C-102, DCR = 0.05Ω
Figure 25. Low Output-Noise Regulator (<1mV)
L1
68µH
R2
3.92k
1%
R1
1.00k
1%
6.0V
C3
3300pF
V
OUT
L2
1µH
C2
220µF
10V
= 1.23 1+
13
V
IN
V
OUT
MIC29150
C3
100µF
10V
GND
2
R2
R1
V
OUT
5V/1A
C4
22µF
10V
April 1998• 4-117
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