Datasheet

LTC3642
17
3642fc
TYPICAL APPLICATIONS
Figure 11. High Efficiency 5V Regulator
Efficiency vs Load Current
V
IN
LTC3642
RUN
C
IN
4.7µF
HYST
3642 F11a
SW
V
IN
5V TO 45V
V
OUT
5V
V
FB
SS
I
SET
GND
L1
220µH
R1
4.2M
R2
800k
C
IN
: TDK C5750X7R2A475MT
C
OUT
: AVX 1812D107MAT
L1: TDK SLF7045T-221MR33-PF
C
OUT
100µF
C
SS
47nF
R
SET
3.3V, 50mA Regulator with Peak Current Soft-Start, Small Size Soft-Start Waveforms
V
IN
LTC3642
RUN
C
IN
1µF
SS
3642 TA02a
SW
V
IN
4.5V TO 24V
V
OUT
3.3V
50mA
V
FB
HYST
I
SET
GND
L1
47µH
R1
294k
R2
93.1k
C
IN
: TDK C3216X7R1E105KT
C
OUT
: AVX 08056D106KAT2A
L1: TAIYO YUDEN CBC2518T470K
C
OUT
10µF
C
SS
0.1µF
OUTPUT VOLTAGE
1V/DIV
INDUCTOR CURRENT
20mA/DIV
2ms/DIV
3642 TA03b
LOAD CURRENT (mA)
1
88
EFFICIENCY (%)
89
90
91
92
94
10 100
3642 F11b
93
V
IN
= 10V
R
SET
= 750k
I
SET
OPEN
R
SET
= 500k
Positive-to-Negative Converter Maximum Load Current vs Input Voltage
V
IN
LTC3642
RUN
C
IN
1µF
HYST
3642 TA04a
SW
V
IN
4.5V TO 33V
V
OUT
–12V
V
FB
SS
I
SET
GND
L1
100µH
R1
1M
R2
71.5k
C
IN
: TDK C3225X7R1H105KT
C
OUT
: MURATA GRM32DR71C106KA01
L1: TYCO/COEV DQ6530-101M
C
OUT
10µF
INPUT VOLTAGE (V)
5
MAXIMUM LOAD CURRENT (mA)
30
40
45
3642 TA04b
20
10
15
25
35
10
20
30
40
50
25
35
15
45
V
OUT
= –3V
V
OUT
= –5V
V
OUT
= –12V