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