Service manual

Table: Semi-standby switching logic
Condition
Semi Stdby pin
12 IC7910
Stand By pin
13 on main uP
Remarks
Normal High High
PIP ON, TV ON,Main
Front End ON
Stand By Low Low
PIP OFF, TV
OFFMain Front End
OFF
Semi
Stdby
Low High
PIP OFF, TV
OFFMain Front End
ON
Power Supply
The power supplies used by PIP panel are from the main board 5V, 8V and 33V (for
tuner only). The 5V is supplied to tuner 1900, VIF IC7914 and switching circuitry of
IC7801 & IC7916. +3V3 is derived from 5V are regulated by TS7891 & D6890. +3V3
voltage is mainly used by PIP processor circuitry. The 8V is mainly supplied to the fast
switching IC7919 TDA8601.