Panasonic PT-TW230U Service Manual page 69

IC Block Diagrams
● MR4010 <Power OSC, IC631>
Z / C
F / B
● NJW1156<Audio Selector,IC5001>
Latch circuit reset
comparator
UVLO comparator
-
+
V
OVP comparator UL
-
+
V
OVP
Thermal Shutdown circuit
Zero current detection
1
circuit
Turn-on dead timer
Standby circuit
V
ref
I
F/B
2
-
+
ON width timer
VCC
4
Start-up circuit UVLO
comparator
- -
Start-up circuit
+ +
V
CC(start)
V
CC(startup off)
/V
CC(stot)
/V
CC(startup on)
R
Q
S
Soft drive circuit
S
Q
R
OCP threshold comparator
+
-
V
TH(OCL)
Burst mode OCP threshold comparator
+ Restart timer
-
V
TH(burst limit)
3
GND
-69-
VIN Collector
7 9
Q1
5
Emitter / OCL