Panasonic EURO 4 Chassis, Technical Manual

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3DQDVRQLF
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Chapter 4 EURO 4D Supplement
1.2. 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 pulse-by-pulse overcurrent
protection, over-voltage protection (with latch) and
thermal protection functions.
1.2.1. General
The mains A.C. voltage which flows via the standby
relay, is then fed via connector W2 to the connector E1
located on the E-Board as mentioned earlier. Once
the A.C. supply is input onto the E-Board, the supply is
fed via the bridge rectifier D801 and transformer T801
primary windings P1/P2 to pin 3 of IC801 and 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.
To
W2
To pin 2
IC850
+B