Acer AM501, Service Manual

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6.0 OPERATION THEOREM
6.1 H & V sync. processor
The key component of this block is U2, it's function is separate horizontal sync, and vertical sync. To get
the polarity fixed V-out, H-out.
6.2 Vertical deflection
The vertical deflection circuit including synchronizer, vertical oscillator, vertical driver, vertical output
amplifier.
6.2.1 Vertical synchronizer
The vertica1 sync. signal comes from U2 then enter at pin 2 of U401 (TDA9111), to synchronize the
vertical oscillator.
6.2.2 Vertical oscillator and driver circuit
The vertical oscillator is at pin 20,21,22 of U401 and the peripheral component, the vertical linearity can
be set by IIC.
U401 TDA9111 also build-in a vertical driver, a saw-tooth signal output from pin 23.
6.2.3 Vertical output amplifier and vertical centering circuit
U601 TDA8172 is the output amplifier, drive a saw-tooth current to vertical deflection yoke. To move
display up or down. It can be set by IIC.