Datasheet

LT1940/LT1940L
18
1940fa
3.3V, ±5V
Low Ripple, Low Profile 12V to 3.3V/2.4A
Maximum Height = 2.1mm
V
IN
10V TO 25V
BOOST1
SW1
FB1
V
C1
PG1
RUN/SS1
BOOST2
SW2
FB2
V
C2
PG2
RUN/SS2
LT1940
V
IN
GND
1940 TA05
220pF
C2
10µF
C4
10µF
C1
10µF
C3
4.7µF
0.1µF 0.1µF
1µF
20k
330pF
15k
10.0k
16.5k
30.1k
100k
L2
4.7µH
L1
3.3µH
PGOOD
OUT2
5V
600mA
OUT3
–5V
300mA
OUT1
3.3V
1.4A
D2
10.0k
D1
D3A
1nF 2.2nF
D3B
D5
47k
–5V LOAD SHOULD BE
LESS THAN 1/2 5V LOAD
(SEE DESIGN NOTE 100).
C1, C2, C4: TAIYO YUDEN JMK316BJ106ML
C3: TAIYO YUDEN TMK325BJ475ML
D1, D2: MICROSEMI UPS140 OR ON SEMI MBRM140
D3: BAT-54A
D5: ON SEMI MBR0530
L1: SUMIDA CR43-3R3
L2: COILTRONICS CTX5-1A
TYPICAL APPLICATIO S
U
V
IN
6V TO 16V
RUN/SS1
RUN/SS2
PG1
PG2
V
C1
V
C2
FB1
FB2
BOOST1
SW1
BOOST2
SW2
LT1940
V
IN
GND
C1
22µF
C3
4.7µF
0.1µF
0.1µF
6.8k
16.5k
100k
L2
4.1µH
L1
4.1µH
OUT2
3.3V
2.4A
D2
D3B
D1
D3A
10.0k
680pF
330pF
1nF
D1, D2: MICROSEMI UPS120
D3: BAT-54A
L1, L2: SUMIDA CDRH5D18-4R1
C1: TAIYO YUDEN JMK316BJ226ML
C3: TAIYO YUDEN EMK325BJ475MN
PGOOD
1940 TA06