KX-B620 Series
KX-B520 Series
1) Function
Lamp drive circuit is on the power supply board.
Control signals for Lamp drive circuit are supplied from CPU.
Lamp driver lights the fluorescent lamp at high frequency to prevent flickering.
It also preheats the filament just before turning it on to reduce blackening. (increase
its life)
LAMPPRE
LAMPTON
Approx 2.5 sec.
Fig. 24 Timing Chart
CONTROL BOARD
MAIN UNIT
Fig. 25 Circuit Diagram
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