Datasheet

10
LT1620/LT1621
TYPICAL APPLICATIONS
U
High Efficiency Buck Constant Current Source
Programmable Constant Current Source
AVG
PROG
V
CC
+IN
SENSE
LT1620MS8
1
2
3
4
8
7
I
OUT
GND
–IN
6
5
0.1µF
10k
1%
R
PROG
18k
0.1µF
1µF
I
PROG
2N3904
22Ω
VN2222LM
OUTIN
GNDSHDN
SHUTDOWN
0.1µF
6V
TO 28V
470Ω
0.1Ω
LT1121CS8-5
0.1µF
I
OUT

0A TO 1A
I
OUT
= (I
PROG
)(10,000)
R
PROG
= 40k FOR 1A OUTPUT
LT1620/21 • TA01
81
53
D45VH10
+
AVG
PROG
PROG2
+IN
SENSE
LT1620GN
1
3
5
16
14
I
OUT
GND
13
9
AVG2
6
MODE
12
V
CC
8
–IN
11
47k
0.047 µF
I
OUT
0A TO 1A
LT1620/21 • TA04
MBRS130T3
20k
0.1µF
10k
1%
I
PROG
R
PROG
10k
820Ω
4.7k
1µF
33k
2N7002
2N7002
2N4403
2N4401

10k
4.7k

Si9405

22µF
25V
TPS
22µF
25V
TPS
0.1µF
5V
6V TO
15V

50µH
CTX50-4

0.05Ω
I
OUT
= (I
PROG
)(20,000)
R
PROG
= 90k FOR 1A OUTPUT
+ +