Datasheet
SLUS430A – APRIL 1999 – REVISED DECEMBER 2000
9
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
The evaluation circuit of the UCC3960 as the primary-side startup circuit and UC38C45 as the secondary-side
controller is shown in Figure 2.
UDG–99099
1
2
3
4
8
7
6
5
1
3
2
4
8
6
7
5
VREF
OUT
GND
COMP
FB
CS
RT
RT 80 k
1F
200
300
100 pF
1F
6.8 k
2.7 nF
0.1 F
4.7 F
0.1 F 36 k
1000 pF
1000 pF
36 k
10k
REF
SS
FB
ISET
VDD
OUT
GND
CS
12 V
0.1 F
12 V
L
M
= 5.4 H
0.5
4.7 k
1 k
470
F
470 F
UP4–101
MUR610 OUT
IRF530
MUR110
10
V
IN
UCC3960
UCC38C45
VDD
Figure 2. Evaluation Circuit UCC3960