LT3975
TYPICAL APPLICATIONS
5V Step-Down Converter
4V Step-Down Converter with a High Impedance Input Source
V
IN
5.7V TO 42V
+
24V
V
IN
V
IN
V
5.49M
499k
OFF ON
EN
PG
BOOST
SW
PG
EN
BOOST
SW
–
4.7µH
4.7µH
0.47µF
0.47µF
+
C
BULK
10µF
PDS360
PDS360
LT3975
LT3975
100µF
SS
RT
OUT
FB
SS
RT
OUT
FB
V
V
1M
1M
OUT
OUT
5V
4V
10pF
10pF
2.5A
2.5A
SYNC
GND
SYNC
GND
10nF
47nF
10µF
47µF
1210
47µF
1210
54.9k
316k
54.9k
432k
3975 TA02
3975 TA05
f = 800kHz
L = IHLP-2020CZ-01
f = 800kHz
L = IHLP-2525EZ-01
12V Step-Down Converter
2.5V Step-Down Converter
V
DFLS160
IN
12.9V TO 42V
V
IN
4.3V TO 42V
V
IN
V
IN
BOOST
SW
OFF ON
EN
PG
BOOST
SW
0.47µF
6.8µH
10µH
0.47µF
OFF ON
EN
PG
PDS360
10µF
LT3975
10µF
PDS360
LT3975
SS
RT
OUT
FB
V
1M
OUT
SS
RT
OUT
FB
12V
V
2.5V
2.5A
1M
OUT
10pF
2.5A
SYNC
GND
10nF
10pF
22µF
1210
×2
SYNC
GND
10nF
54.9k
110k
100µF
1210
130k
909k
3975 TA03
f = 800kHz
L = IHLP-3232CZ-01
3975 TA06
f = 400kHz
L = IHLP-2525EZ-01
5V, 2MHz Step-Down Converter with Power Good
1.8V Step-Down Converter
V
DFLS160
IN
5.9V TO 18V
V
IN
4.3V TO 27V
(42V TRANSIENTS)
0.47µF
2.2µH
BOOST
SW
V
IN
V
IN
OFF ON
EN
OFF ON
EN
PG
BOOST
SW
PDS360
3.3µH
0.47µF
150k
LT3975
4.7µF
PGOOD
PG
OUT
10µF
PDS360
LT3975
SS
RT
V
1M
OUT
SS
RT
OUT
FB
5V
FB
GND
V
1.8V
2.5A
499k
10pF
OUT
10pF
2.5A
SYNC
10nF
22µF
1210
SYNC
GND
10nF
14.7k
316k
100µF
1210
97.6k
1M
3975 TA04
f = 2MHz
L = IHLP-2525CZ-01
3975 TA07
f = 500kHz
L = IHLP-2020CZ-01
3975f
22