Datasheet

19
LTC1421/LTC1421-2.5
APPLICATIONS INFORMATION
WUU
U
10 9 13 14 8 11 15 6 7
2
24
4 3 1
LTC1421
16
R4
300Ω
1/8W
R3 56k 1/2W
Q2 MPSA06
Q1
IRFR9110
C1 1µF
–48V
171819202122
5
S1
12
23
STAGGERED CONNECTOR
C2 2.2µF
25V
R1 5.1k 1W
D1
5.1V
+
C3
2.2µF
25V
C5 4.7µF 50V
C9 0.33µF
50V
+
+
C4 4.7µF 50V
3
5
1
4
+
C6 100µF
100V
L1
100µH
D4
MBR3100
Q3
2N5401
Q4
2N5401
D3
MBR3100
D2 7.5V
+
1421 F20
PC BOARDBACKPLANE
–48V
–48V –48V
R5 10k 1/2W R6 402Ω 1/8W
R9 1k 1/8W
R8 1k 1/8W
R2 15k 1/8W
LT1170HVCT
V
CC
V
C
SW
GND FB
R10 4.32k 1/8W
R11 4.32k 1/8W
R13 1.24k 1/8W
R14 4.64k 1/8W
R12 10k 1/8W
V
CC
5V 3A
RESET
C7 1000µF 25V
+ +
C8 1000µF 25V
1µF
Figure 20. –48V to 5V Hot Swappable Supply Using the LT1170HVCT