July 2001
1
MIC4575
MIC4575
Micrel
MIC4575
200kHz Simple 1A Buck Regulator
Final Information
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 200
A
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 compensa-
tion is provided internally.
The MIC4575 is available in TO-220 (T) and TO-263 (U)
packages for the industrial temperature range.
Typical Applications
C1
150F
35V
D1
1N5819
C2
330F
16V
L1
68H
GND
FB
SW
MIC4575-5.0BT
SHDN
8V to 24V
5.0V/1A
V
IN
3
4
2
5
1
Shutdown
Enable
Fixed Regulator
C1
22F
35V
MBRS130LT3
C2
330F
6.3V
L1
68H
GND
FB
MIC4575BU
SW
SHDN
6V to 24V
3.6V/1A
V
IN
R2
2.37k
1%
R1
1.24k
1%
4
2
3
1
5
C3
3300pF
D1
Shutdown
Enable
Adjustable Regulator
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
< 200
A 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 PentiumTM
and similar microprocessors
Micrel, Inc. 1849 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 944-0970 http://www.micrel.com
MIC4575
Micrel
MIC4575
2
July 2001
Ordering Information
Part Number
Voltage
Temperature Range
Package
MIC4575-3.3BT
3.3V
40
C to +85
C
TO-220-5
MIC4575-5.0BT
5.0V
40
C to +85
C
TO-220-5
MIC4575BT
Adjustable
40
C to +85
C
TO-220-5
MIC4575-3.3BU
3.3V
40
C to +85
C
TO-263-5
MIC4575-5.0BU
5.0V
40
C to +85
C
TO-263-5
MIC4575BU
Adjustable
40
C to +85
C
TO-263-5
Pin Description
Pin Number
Pin Name
Pin Function
1
V
IN
Supply Voltage (Input): Unregulated +4V to +40V supply voltage.
2
SW
Switch (Output): Emitter of NPN output switch. Connect to external storage
inductor and Shottky diode.
3,
TAB
GND
Ground
4
FB
Feedback (Input): Output voltage feedback to regulator. Connect to output
of supply for fixed versions. Connect to 1.23V tap of resistive divider for
adjustable versions.
5
SHDN
Shutdown (Input): Logic low enables regulator. Logic high (> 2.4V) shuts
down regulator.
Pin Configuration
TAB
5
SHDN
4
FB
3
GND
2
SW
1
V
IN
5-Lead TO-220 (T)
TAB
5
SHDN
4
FB
3
GND
2
SW
1
V
IN
5-Lead TO-263 (U)
July 2001
3
MIC4575
MIC4575
Micrel
Electrical Characteristics
(Note 2)
V
IN
= 12V; I
LOAD
= 200mA; T
J
= 25
C, bold values indicate 40
C
T
J
+85
C; unless noted.
Parameter
Condition
Min
Typ
Max
Units
MIC4575 [Adjustable]
Feedback Voltage
1.217
1.230
1.243
V
Feedback Voltage
8V
V
IN
24V, 0.2A
I
LOAD
1A
1.193
1.230
1.267
V
1.180
1.280
V
Efficiency
I
LOAD
= 1A, V
OUT
= 5V
77
%
Feedback Bias Current
50
100
nA
500
nA
MIC4575-3.3
Output Voltage
3.234
3.3
3.366
V
Output Voltage
6V
V
IN
24V, 0.2A
I
LOAD
1A
3.168
3.3
3.432
V
3.135
3.465
V
Efficiency
I
LOAD
= 1A
72
%
MIC4575-5.0
Output Voltage
4.900
5.0
5.100
V
Output Voltage
8V
V
IN
24V, 0.2A
I
LOAD
1A
4.800
5.0
5.200
V
4.750
5.250
V
Efficiency
I
LOAD
= 1A
77
%
MIC4575 / -3.3 / -5.0
Oscillator Frequency
180
200
220
kHz
Saturation Voltage
I
OUT
= 1A
1
1.3
V
1.5
V
Maximum Duty Cycle (On)
FB connected to 0V
90
95
%
Current Limit
Peak Current, t
ON
3
s
1.7
2.2
3.0
A
1.3
3.2
A
Output Leakage Current
V
IN
= 24V, FB connected to 0V
Output = 0V
0
2
mA
Output = 1V
7.5
30
mA
Quiescent Current
5
10
mA
Standby Quiescent Current
SHDN = 5V (regulator off)
50
200
A
SHDN Input Logic Level
V
OUT
= 0V (regulator off)
2.2
1.4
V
2.4
V
V
OUT
= 3.3 or 5V (regulator on)
1.2
1.0
V
0.8
V
SHDN Input Current
SHDN = 5V (regulator off)
4
30
A
SHDN = 0V (regulator on)
10
0.01
10
A
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.
Note 2:
Specification for packaged product only.
Absolute Maximum Ratings
Supply Voltage (V
IN
) Note 1 ....................................... +40V
Shutdown Voltage (V
SHDN
) .......................... 0.3V to +36V
Output Switch (V
SW
) steady state ................................. 1V
Storage Temperature (T
S
) ......................... 65
C to 150
C
Operating Ratings
Supply Voltage (V
IN
) ................................................... +24V
Junction Temperature ............................................. +150
C
Package Thermal Resistance
TO-220, TO-263 (
JA
) ......................................... 65
C/W
TO-220, TO-263 (
JC
) ........................................... 2
C/W
MIC4575
Micrel
MIC4575
4
July 2001
200kHz
Oscillator
1.23V
Bandgap
1A
Switch
Thermal
Shutdown
Current
Limit
Driver
Internal
Regulator
FB
SW
GND
V
IN
+24V max.
C
IN
C
OUT
L1
D1
Shutdown
Enable
SHDN
V
OUT
MIC4575
[Adjustable]
R1
R2
Com-
parator
Error
Amp.
V
OUT
V
REF
R1
R2
+ 1
R1
R2
V
OUT
V
REF
1
200kHz
Oscillator
1.23V
Bandgap
1A
Switch
Thermal
Shutdown
Current
Limit
Driver
Internal
Regulator
FB
SW
GND
V
IN
+24V max.
C
IN
C
OUT
L1
D1
Shutdown
Enable
SHDN
V
OUT
MIC4575-x.x
R1
R2
Com-
parator
Error
Amp.
Block Diagram with External Components
Adjustable Step-Down Regulator
Block Diagram with External Components
Fixed Step-Down Regulator
Block Diagrams
July 2001
5
MIC4575
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 logic-
high shuts down the internal regulator which reduces the
current to typically 50
A.
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 com-
parator 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
IN,
through external storage inductor L1, to
output capacitor C
OUT
and the load. Energy is stored in the
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
OUT
provides stabilization and
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.
For a mathematical approach to component selection and
circuit design, refer to Application Note 14.
C1
150F
35V
D1
1N5819
C2
330F
16V
L1
68H
GND
FB
SW
MIC4575-3.3BT
SHDN
6V to 24V
3.3V/1A
V
IN
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C2 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola
1N5819
L1
Sumida
RCH106-680K, DCR = 0.22
L1
Bi
HM77-11003, DCR = 0.233
, Note 2
3
4
2
5
1
Figure 1. 6V24V to 3.3V/1A Buck Converter
Through Hole
C1
150F
35V
D1
1N5819
C2
330F
16V
L1
68H
GND
FB
SW
MIC4575-5.0BT
SHDN
8V to 24V
5.0V/1A
V
IN
C1 Nichicon
UPL1J151MPH, ESR = 0.12
C2 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola
1N5819
L1
Sumida
RCH106-680K, DCR = 0.22
L2
Bi
HM77-11003, DCR = 0.233
, Note 2
3
4
2
5
1
Figure 2. 8V24V to 5V/1A Buck Converter
Through Hole
C1
68F
63V
MBR160
C2
330F
16V
L1
150H
GND
FB
SW
MIC4575BT
SHDN
16V to 24V
12V/1A
V
IN
R2
13.0k
1%
R1
1.50k
1%
C1 Nichicon
UPL1J680MPH, ESR = 0.17
C2 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola
MBR160
L1
Sumida
RCH110-151K, DCR = 0.23
5
1
4
2
3
Figure 3. 16V24V to 12V/1A Buck Converter, Through Hole
Note 2: Surface-
mount component.
MIC4575
Micrel
MIC4575
6
July 2001
C1
22F
35V
MBRS130LT3
C2
330F
6.3V
L1
68H
GND
FB
MIC4575BU
SW
SHDN
6V to 24V
3.3V/1A
V
IN
R2
2.49k
1%
R1
1.50k
1%
C1 AVX
TPSE226M035R0300, ESR = 0.3
C2 AVX
TPSE337M006R0100, ESR = 0.1
D1 Motorola
MBRS130LT3
L1
Coiltronics CTX68-4P, DCR = 0.238
4
2
3
1
5
C3
3300pF
D1
Figure 4. 6V24V to 3.3V/1A Buck Converter
Low-Profile Surface Mount
C1
22F
35V
MBRS130LT3
C2
220F
10V
L1
68H
GND
FB
MIC4575BU
SW
SHDN
8V to 24V
5V/1A
V
IN
R2
3.01k
1%
R1
1.00k
1%
C1 AVX
TPSE226M035R0300, ESR = 0.3
C2 AVX
TPSE227M010R0100, ESR = 0.1
D1 Motorola MBRS130LT3
L1
Coiltronics CTX68-4P, DCR = 0.238
4
2
3
1
5
C3
3300pF
D1
Figure 5. 8V24V to 5V/1A Buck Converter
Low-Profile Surface Mount
C1
10F
50V
D1
SS26
C2
68F
20V
L1
150H
GND
FB
MIC4575BU
SW
SHDN
16V to 24V
12V/1A
V
IN
R2
13.0k
1%
R1
1.50k
1%
C1 Tokin
C55YU1H106Z
C2 AVX
TPSE686M020R0150, ESR = 0.15
D1 General Instruments SS26
L1
Coiltronics CTX150-4, DCR = 0.372
4
2
3
1
5
C3
3300pF
Figure 6. 16V24V to 12V/1A Buck Converter
Low-Profile Surface Mount
C1
150F
35V
D1
MBRS130LT3
C2
470F
16V
L1
68H
GND
FB
SW
MIC4575-3.3BU
SHDN
6V to 24V
3.3V/1A
V
IN
C1 Sanyo
35CV150GX, ESR = 0.17
C2 Sanyo
16CV470GX, ESR = 0.17
D1 Motorola
MBRS130LT3
L1
Coilcraft
DO3316P-683, DCR = 0.16
L1
Bi
HM77-11003, DCR = 0.233
3
4
2
5
1
Figure 7. 6V24V to 3.3V/1A Buck Converter
Lower-Cost Surface Mount
C1
150F
35V
D1
MBRS130LT3
C2
470F
16V
L1
68H
GND
FB
SW
MIC4575-5.0BU
SHDN
8V to 24V
5V/1A
V
IN
C1 Sanyo
35CV150GX, ESR = 0.17
C2 Sanyo
16CV470GX, ESR = 0.17
D1 Motorola
MBRS130LT3
L1
Coilcraft
DO3316P-683, DCR = 0.16
L1
Bi
HM77-11003, DCR = 0.233
3
4
2
5
1
Figure 8. 8V24V to 5V/1A Buck Converter
Lower-Cost Surface Mount
C1
47F
50V
X2
SS26
C2
470F
16V
L1
150H
GND
FB
SW
MIC4575BU
SHDN
16V to 24V
12V/1A
V
IN
R2
13.0k
1%
R1
1.50k
1%
C1 Nichicon
UUX1H470MT1GS, ESR = 0.4
C2 Sanyo
16CV470GX, ESR = 0.17
D1 General Instruments SS26
L1
Coiltcraft
DO5022P-154, DCR = 0.218
5
1
4
2
3
Figure 9. 16V24V to 12V/1A Buck Converter
Lower-Cost Surface Mount
C1
150F
35V
GND
FB
SW
MIC4575-5.0BT
SHDN
8V to 18V
V
IN
C1 Nichicon
UPL1V151MPH
ESR = 0.13
C2 Nichicon UPL1C681MPH
ESR = 0.065
D1 Motorola 1N5819
L1
Coiltronics PL52A-10-500
DCR = 0.045
1
5
4
2
3
1N5819
D1
C2
680F
16V
-5V/0.2A
L1
10H
Figure 10. 8V18V to 5V/0.2A Buck-Boost Converter
Through Hole
July 2001
7
MIC4575
MIC4575
Micrel
C1
150F
35V
GND
FB
SW
MIC4575BT
SHDN
4.75V to 5.25V
V
IN
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C2 Nichicon
UPL1C681MPH, ESR = 0.065
D1 Motorola 1N5819
L1
Coiltronics PL52A-15-500, DCR = 0.054
1
5
4
2
3
1N5819
D1
C2
680F
16V
-5V/0.3A
L1
15H
R1
3.01k
1%
R2
1.00K
1%
R3
10K
C3
0.01F
R4
5.1K
C4
1000pF
Figure 11. 5V to 5V/0.3A Buck-Boost Converter
Through Hole
C1
22F
35V
D1
MBRS130LT3
GND
FB
SW
MIC4575BU
SHDN
V
IN
8V to 18V
V
IN
C1 AVX
TPSE226M035R0300, ESR = 0.3
C2 AVX
TPSE227M010R0100, ESR = 0.1
C4 AVX
TPSE227M010R0100, ESR = 0.1
D1 Motorola MBRS130LT3
T1 Coiltronics CTX68-4P, DCR = 0.238
L1
Coilcraft DO1608C-102
3
4
2
5
1
T1
68H
L1
1H
C4
220F
10V
R2
3.01k
1%
R1
1.00K
1%
C3
3300pF
C2
220F
10V
V
OUT
5V/1A
5mV
P-P
1
2
3
4
Figure 12. Low Output-Noise Regulator (5mV Output Ripple )
C1
22F
35V
D1
MBRS130LT3
GND
FB
SW
MIC4575BU
SHDN
V
IN
8V to 18V
V
IN
C1 AVX
TPSE226M035R0300, ESR = 0.3
C2 AVX
TPSE227M010R0100, ESR = 0.1
C4 AVX
TPSE227M010R0100, ESR = 0.1
C5 AVX
TPSE227M010R0100, ESR = 0.1
D1 Motorola MBRS130LT3
D2 Motorola
MBRS130LT3
T1 Coiltronics CTX68-4P, DCR = 0.238
3
4
2
5
1
T1
68H
R2
3.01k
1%
R1
1.00K
1%
C3
3300pF
C2
220F
10V
+V
OUT
/+I
OUT
5V/0.5A
-V
OUT
/-I
OUT
-5V/0.5A
at V
IN
15V
Load Regulation
5%
D2
MBRS130LT3
L1
C5
220F
10V
2
1
3
4
C4
220F
10V
DC
+V
OUT
0.5V
V
IN
0.5V
DC
40% then
I
OUT
+I
OUT
+I
OUT
+ I
OUT
1A
DC
40% then
I
OUT
I
OUT
(1
DC)
Figure 13. Split
5V Supply
MIC4575
Micrel
MIC4575
8
July 2001
C1
150F
35V
D1
1N5819
L1
68H
GND
FB
SW
MIC4575BT
SHDN
V
IN
4V to 24V
V
IN
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C2 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola
1N5819
L1
Coiltronics PL52B-68-500, DCR = 0.095
U2 Micrel LM4041CIZ-1.2
3
4
2
5
1
Q1
2N4339
R3
3.3K
U2
LM4041CIZ-1.2 V
OUT
R1
200K
R2
15k
C2
330F
16V
R4
330
0.5W
(0-12V)/0.5A
V
OUT
Min = 60mV
V
IN min
V
OUT
0.9
1.5V
V
IN min
V
OUT
2.5V
and
Figure 14. Adjustable (0V12V) Output-Voltage Regulator
C1
150F
35V
D1
1N5819
GND
FB
SW
MIC4575BT
SHDN
V
IN
4V to 15V
V
IN
C1 Nichicon UPL1V151MPH, ESR = 0.12
C2 Nichicon UPL1C331MPH, ESR = 0.12
D1 Motorola 1N5819
L1
Coiltronics PL52B-68-500, DCR = 0.095
U2 National LM358
3
4
2
5
1
L1
68H
V
OUT
1V/1A
1
2
3
R1
249
1%
R2
1.00k
1%
C2
330F
16V
R3
1k
U2
LM358
U1
Figure 15. Low Output-Voltage Regulator (1V)
C1
150F
35V
D1
1N5819
L1
68H
GND
FB
SW
MIC4575BT
SHDN
V
IN
9V to 24V
V
IN
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C2 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola
1N5819
L1
Coiltronics PL52B-68-500, DCR = 0.095
U2 National LM358
Q1 Siliconix
VN2222LL
R1 KRL
SP-1/2-A1-0R250J
3
4
2
5
1
R4
3k
1
2
3
U2
LM358
C3
0.01F
DZ1
1N5244
14V
R5
1.00k
1%
R1
0.25
R3
10K
C2
330F
16V
D2
1N5819
6-8 Cells
V
BATT
R2
200
1%
Q1
VN2222LL
C4
1000pF
I
OUT
1A
V
IN min
V
BATT
0.9
2.5V
I
OUT
1.23V
R5
R2
R1
Figure 16. 1A Battery Charger (68 cells)
July 2001
9
MIC4575
MIC4575
Micrel
C3
0.01F
C1
150F
35V
D1
1N5819
GND
FB
SW
MIC4575-BT
SHDN
V
IN
8V to 24V
V
IN
U1 Micrel MIC4575BT
U2 National LM358
U3 Micrel LM4041CIZ-1.2
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C2 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola
1N5819
D2 Motorola
1N5819
D3 Motorola
1N4148
L1
Coiltronics PL52B-68-500, DCR = 0.095
R1 KRL SP-1-A1-0R100J
Q1 Siliconix VN2222LL
3
4
2
5
1
3
2
1
DZ1
1N5244
14V
R3
10k
R1
0.1
R2
100
1%
C2
330F
16V
D2
1N5819
7
8
5
6
4
V
IN
R4
1.21k
1%
U2B
1/2 LM358
Q1
VN2222LL
VR1
10k
U3
LM4041CIZ-1.2
V
IN
R5
10k
2-8 Cells
V
BATT
I
OUT
0.1A to 1A
U2A
1/2LM358
L1
68H
R6
3k
C4
1000pF
R7
1k
V
IN min
V
BATT
/ 0.9
2.5V
D3
1N4148
Figure 17. 0.1A1A Variable-Current Battery Charger
C3
0.01F
C1
150F
35V
D1
1N5819
GND
FB
SW
MIC4575-BT
SHDN
V
IN
8V to 24V
V
IN
U1 Micrel MIC4575BT
U2 National LM358
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C2 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola 1N5819
D2 Motorola
1N5819
D3 Motorola
1N4148
L1
Coiltronics PL52B-68-500, DCR = 0.095
R1 KRL SP-1-A1-0R100J
Q1 Siliconix VN2222LL
3
4
2
5
1
3
2
1
DZ1
1N5244
14V
R3
10k
R1
0.1
R2
100
1%
C2
330F
16V
D2
1N5819
2-8 Cells
V
BATT
I
OUT
1A
U2A
1/2LM358
L1
68H
R5
3k
C4
1000pF
R6
1k
7
8
5
6
4
V
IN
R4
1.21k
1%
U2B
1/2 LM358
Q1
VN2222LL
V
IN min
V
BATT
/ 0.9
2.5V
I
OUT
1.23V
R4
R2
R1
D3
1N4148
Figure 18. 1A Battery Charger (28 Cells)
MIC4575
Micrel
MIC4575
10
July 2001
L1
68H
GND
FB
MIC4575BT
V
SW
SD
V
IN
C1 Nichicon
UPL1J680MPH, ESR = 0.17
C2 Nichicon
UPL1J680MPH, ESR = 0.17
C4 AVX
TPSE227M010R0100, ESR = 0.1
D1 Motorola
MBRS160
L1
Coiltronics PL52B-68-500, DCR = 0.095
4
2
3
1
5
C2
68F
63V
D1
MBR160
V
IN
8V to 24V
C1
68F
63V
U1
C3
0.01F
+V
SENSE
+V
V
SENSE
V
10 ft Wire
0.5
C4
220F
10V
V
OUT
5V/1A
R4
10
R1
30
R2
3.01k
1%
R3
1.00k
1%
Figure 19. Remote-Sensing Regulator
C1
22F
35V
D1
MBRS130LT3
GND
FB
SW
MIC4575BU
SHDN
V
IN
6V to 18V
V
IN
C1 AVX
TPSE226M035R0300, ESR = 0.3
C2 AVX
TPSE686M020R0150, ESR = 0.15
C3 AVX
TPSE686M020R0150, ESR = 0.15
C4 AVX
TPSE686M020R0150, ESR = 0.15
D1 Motorola MBRS130LT3
D2 Motorola MBRS130LT3
T1 Coiltronics CTX150-4, DCR = 0.372
Q1 Siliconix
Si 9435, PMOS
3
4
2
5
1
T1
150H
C2
68F
R2
13.0k
1%
R1
1.50K
1%
C5
3300pF
C3
68F
20V
V
OUT
12V/100mA
1
2
T1
MBRS130LT3
D2
V
OUT
12V/100mA
(11V to 12V)
C4
68F
20V
3
4
D3
1N4148
Q1
Si9435
R3
1k
Figure 20. 6V18V to Split
12V/100mA Supply
C1
150F
35V
GND
FB
SW
MIC4575BU
SHDN
V
IN
8V to 24V
V
IN
U1 Micrel
MIC4575BT
U2 National
LM358
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C2 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola 1N5819
D2 Motorola 1N5819
DZ1 Motorola
1N5244
L1
Bi
HM77-11003, DCR = 0.233
R1 KRL
SP-1/2-A1-0R100J
3
4
2
5
1
U1
V
BATT
28 Cells
D2
1N5819
C2
330F
16V
R1
0.1
R2
10k
1%
DZ1
1N5244
14V
R4
10k
6
5
4
7
8
C4
R3
113k
1%
C3
0.1F
D1
1N5819
L1
68H
I
OUT
1A
U2B
1/2 LM358
I
OUT
=
1.23V
R1
R2
R2
R3
0.01F
V
IN
8
V
IN min
=
V
BATT
0.9
+ 2.5V
Figure 21. 1A Battery Charger
July 2001
11
MIC4575
MIC4575
Micrel
C1
150F
35V
GND
FB
SW
MIC4575BT
SHDN
V
IN
4V to 24V
V
IN
U1 Micrel
MIC4575BT
U2 National
LM358
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C2 Nichicon
UPL1C102MPH, ESR = 0.047
D1 Motorola 1N5819
L1
Bi
HM77-11003, DCR = 0.233
3
4
2
5
1
U1
R1
20k
1%
6
5
4
7
8
C4
0.01F
D1
1N5819
L1
68H
R4
2k
1%
R3
20k
1%
R5
10K
R2
2k
1%
R6
220
C2
1000F
16V
R6
330
0.5W
V
OUT
0V12V
V
OUTmin
= 60mV
C3
3300pF
1
2
3
U2B
1/2LM358
U2A
1/2LM358
R1 = R3 and R2 = R4
V
IN
V
IN min
=
V
OUT
0.9
+ 2.5V
V
OUT max
= 1.23V
1
R1
R2
Figure 22. Improved Adjustable Output-Voltage Regulator (0V12V)
C1
150F
35V
GND
FB
SW
MIC4575BT
SHDN
V
IN
8V to 24V
V
IN
U1 Micrel
MIC4575BT
U2 National
LM358
U3 Micrel
MIC2506BM
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C1 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola 1N5819
D2 Motorola 1N5819
DZ1 Motorala
1N5236
L1
Bi
HM77-11003, DCR = 0.233
Q1 Siliconix
VN2222LL
R1 KRL
SP-1/2-A1-0R100J
3
4
2
5
1
U1
L1
R5
3k
GND
OUT B
OUT A
MIC2506
CTL A
FLG A
U3
R6
1k
C4
1000pF
C5
0.01F
V
IN
D1
1N5819
68H
C3
0.01F
DZ1
1N5236
7.5V
R2
100
1%
R1
0.1
R3
10k
FLG B
IN
CTL B
R10
510k
Bat B
4 Cells
NiCad
Bat A
4 Cells
NiCad
A/B
Bat A
Bat B
Q1
VN2222LL
R7
100k
R8
100k
R4
1.21k
1%
I
OUT
1A
C2
330F
16V
D3
1N4148
4
8
5
6
7
1
2
3
2
3
1
4
7
6
8
5
R9
510k
2
U4A
7404
1
U2A
1/2LM358
U2B
1/2 LM358
Figure 23. Switchable Battery-Pack Charger
MIC4575
Micrel
MIC4575
12
July 2001
C1
150F
35V
GND
FB
SW
MIC4575BT
SHDN
V
IN
12V to 24V
V
IN
U1 Micrel
MIC4575BT
U2 National
LM358
U3 National
LM3420
U4 National
LM339
C1 Nichicon
UPL1V151MPH, ESR = 0.12
C1 Nichicon
UPL1C331MPH, ESR = 0.12
D1 Motorola 1N5819
D2 Motorola 1N5819
DZ1 Motorala
1N5244
L1
Bi
HM77-11003, DCR = 0.233
R1 KRL
SP-1/2-A1-0R100J
Q1 Siliconix
VN2222LL
3
4
2
5
1
U1
L1
R6
3k
GND
LM3420
OUT
U3
R7
1k
C4
1000pF
C5
0.1F
V
IN
D1
1N5819
68H
C3
0.01F
R2
100
1%
R1
0.1
R5
1.0k
1%
COMP
IN
Q1
VN2222LL
R3
1.21k
1%
I
OUT
1A
C2
330F
16V
D3
1N4148
4
8
5
6
7
1
2
3
3
1
8
4
U2A
1/2LM358
U2B
1/2 LM358
C8
0.01F
V
IN
END
C6
0.1F
C7
0.01F
R10
10k
R9
10M
V
IN
R8
10k
R12
100k
R4
13.0k
1%
Q2
2N2222
D2
1N5819
V
BATT
2 Li Cells
1
3
7
6
12
LM339
I
OUT
=
1.24V
R3
R2
R1
I
OUT
= 1.02A
I
OUT
END
60mA
V
IN min
> =
V
BATT
0.9
+ 2.5V
I
OUT
END
1.23V
R2
R3
R5
R4
R1
Figure 24. Lithium-Ion Battery Charger with End-of-Charge Flag
C1
22F
35V
GND
FB
SW
MIC4575BU
SHDN
V
IN
9V to 18V
V
IN
U1 Micrel
MIC4575BU
U2 Micrel
MIC29150-5.0BU
C1 AVX
TPSE226M035R0300, ESR = 0.3
C2 AVX
TPSE227M010R0100, ESR = 0.1
C3 AVX
TPSE106M010R0200, ESR = 0.2
C4 Sprague 293D226X0010C2W
D1 Motorola MBRS130LT3
D2 Motorola MBRS130LT3
L1
Bi
HM77-11003, DCR = 0.233
L2
Coilcraft
D016087C-102, DCR = 0.05
3
4
2
5
1
D1
MBRS130LT3
L1
68H
R2
3.92k
1%
C3
3300pF
C2
220F
10V
R1
1.00k
1%
L2
1H
C3
100F
10V
C4
22F
10V
MIC29150
GND
V
IN
U1
U2
V
OUT
2
1
3
V
OUT
5V/1A
V
OUT
= 1.23
1 +
R2
R1
6.0V
Figure 25. Low Output-Noise Regulator (<1mV)
July 2001
13
MIC4575
MIC4575
Micrel
Package Information
0.018
0.008
(0.46
0.20)
0.268 REF
(6.81 REF)
0.032
0.005
(0.81
0.13)
0.550
0.010
(13.97
0.25)
7
Typ.
SEATING
PLANE
0.578
0.018
(14.68
0.46)
0.108
0.005
(2.74
0.13)
0.050
0.005
(1.27
0.13)
0.150 D
0.005
(3.81 D
0.13)
0.400
0.015
(10.16
0.38)
0.177
0.008
(4.50
0.20)
0.103
0.013
(2.62
0.33)
0.241
0.017
(6.12
0.43)
0.067
0.005
(1.70
0.127)
inch
(mm)
Dimensions:
5-Lead TO-220 (T)
0.067
0.005
0.032
0.003
0.360
0.005
0.600
0.025
0.405
0.005
0.060
0.005
0.176
0.005
8
MAX
0.100
0.01
0.050
0.005
0.015
0.002
0.004+0.004
0.008
SEATING PLANE
0.065
0.010
20
2
DIM. = INCH
5-Lead TO-263 (U)
MIC4575
Micrel
MIC4575
14
July 2001
July 2001
15
MIC4575
MIC4575
Micrel
MIC4575
Micrel
MIC4575
16
July 2001
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.
2001 Micrel Incorporated
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