Datasheet

   
   
SLUS517C − DECEMBER 2002 − REVISED SEPTEMBER 2005
11
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APPLICATION INFORMATION
U1
12
3
16
18
10
5
7
2
UCC2851X
GT1
VSENSE
ISENSE1
IAC
GT2
VREF
VERR
RT
R20
R17
AGND
U2
C1
D3
PGND
L1
+
–
D1
VAC
Q2
C2
D4
15
14
13
11
17
19
20
PWRGND
VAOUT 1
4
6
VFF
MOUT
CAOUT
PKLMT
SS2
8
9
D_MAX
CT_BUFF
GND
ISENSE2
VCC
R3
R4
R18
C8R15
C7
R13
C6
C11
R21
C10
R14
R16
R19
R2
R5
R11
R8
R7
AGND
C4
PGND
C5
R1
AGND
C9
REF
T1
D5
C3
R6
AGND
REF
D6R22
R26
C12
C13
R24
R23
C14
R25
U3
TL431
GND2
GND2
PRIMARY SECONDARY
GND2
+
−
VOUT
D2
Q1
PGND
R9
R10
R12
Figure 1. Typical Application Circuit: Boost PFC and Flyback PWM Power System