Datasheet

4
UCC1809-1/-2
UCC2809-1/-2
UCC3809-1/-2
UDG-99179
T1
80µH
5:1
C10
0.22 µF
R9
2K
3W
R13
1.1K
R11
680
Q3
IRF640
D3
SF24
Q2
2N2907A
D4
1N5240
8
7 6
5
4
3 2 1
UCC3809
U1
FB
REF
SS
RT1
RT2
VDD
OUT
GND
C8
1µF
C9
0.1 µF
C7
0.47 µF
TP1
R5
470
R20
5.62K
C22
0.1 µF
Q4
2N2222A
R18
3.01K
C6
330pF
D1
5231B
D2
1N5245
R7
15K
R6
1K
R8
0.15
3W
R4
6.19K
R3
12.1K
C5
1nF
C4
0.01 µF
Q1
2N2222A
R2
1.1K
ON/OFF
–VIN
C3
1µF
+VIN
C2
150 µF
C1
150 µF
R12
27K
R15
10K
C14
470pF
R16
12.1K
1%
U4
TL431
H11AV1
U3
2
1
4 5
R17
12.1K
1%
C13
0.1 µF
C15
0.015
µF
R19
5.1K
3W
U2
MBR2535CTL
1
3
2
C16
330 µF
6.3V
C17
330 µF
6.3V
C18
330 µF
6.3V
C19
330 µF
6.3V
R14
750
+V
OUT
–V
OUT
R1
5.1k
R10
10
PGND1
PGND1
APPLICATION INFORMATION
Figure 1. Isolated 50W flyback converter utilizing the UCC3809. The switching frequency is 70kHz, Vin = -32V to
-72V, Vout = +5V, Iout = 0A to 10A