Panasonic EURO 4 Chassis Technical Manual page 12

3DQDVRQLF
8.2. Flyback Converter Power Supply
The STR-F6654 is a hybrid IC with built-in
MOS-FET and control IC as well as a separate
oscillation circuit.
It features a small SIP (Single In-line Package) with
isolated body (no bush and micra isolator required)
and requires only a small number of external
components.
Quasi-resonant operation is used to improve the
switching efficiency, which with altered operation in
standby mode allows the supply to fulfil both
power-on and standby roles.
The IC features
protection, over-voltage protection (with latch) and
thermal protection functions.
8.2.1. General
The mains voltage flows through the mains
suppression filter and standby relay, before being
fed via the bridge rectifier D801 and transformer
T801 primary windings P1/P2 to pin 3 of
the drain terminal of the internal MOS-FET
transistor.
As there is no gate control voltage at this time the
operating voltage is not subjected to any load.
12
pulse-by-pulse overcurrent
IC801 and