Sanyo Vizon DP32746 Service Manual page 31

IC1602 Oscillator, Regulator
Z/C
1
F/B 2
IC1603 Oscillator, Regulator
OPAMP
5
OPOUT
6
OPIN–
7
OPIN+
Ifmin
4
Rfmin
Ifstart
2
Rfstart
3
VCO
Cf
Latch circuit reset
UVLO comparator
V
UL
OVP comparator
V
OVP
Thermal Shutdown circuit
Zero current detection
circuit
Turn-on dead timer
Standby circuit
V
ref
I
F/B
ON width timer
V S
12
+
–
DETECTION
V REF
DEAD
TIME
V REF
CONTROL
LOGIC
VCC
4
Start-up circuit UVLO
comparator
V
cc(start)
V
cc(startup off)
V
/ cc(stop) V
/ cc(startup on)
R
Q
S
S
Q
R
OCP threshold comparator
V
Burst mode OCP threshold comparator
V
TH(burst limit)
3
GND
BOOTSTRAP
UV
DRIVER
DRIVING
LOGIC
Iss
1
Css
— 31 —
VIN Corrector
9
7
Start-up circuit
Q1
Soft drive circuit
TH(OCL)
Restart timer
5
Emitter/OCL
V BOOT
16
15
HVG
HVG
DRIVER
14 OUT
LEVEL Vs
SHIFTER
11
LVG
LVG DRIVER
10
GND
Vthe1
+
8
–
EN1
Vthe2
+
9
–
EN2
H.V.
C
BOOT
LOAD