Daewoo 2898ST, Service Manual

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TDA8351 (DC-coupled vertical deflection circuit)
(1) General Description
The TDA8351 is power circuit for use in 90 and 110 color deflection systems for field frequencies of 50 to 120 Hz.
The circuit provides a DC driven vertical deflection output circuit, operating as a high efficient class G system.
(2) Feature
• High efficient fully DC-coupled vertical output bridge circuit
• Vertical fly-back switch
• Guard circuit
• Protection against : - short circuit of the output pins (7 and 4)
- short circuit of the output pins to Vp
• Temperature (thermal) protection
• High EMC immunity because of common mode inputs
• A guard signal in zoom mode.
(3) Block Diagram
(4) Pin Description
PIN SYMBOL DESCRIPTION
1 I drive (pos) input power stage (positive); include Ii(sb) signal bias
2 I drive (neg) input power stage (negative); include Ii(sb) signal bias
3 V p operating supply voltage
4 V o(b) output voltage B
5 GND ground
6 V fb input fly-back supply voltage
7 V o(a) output voltage A
8 V o(guard) guard output voltage (Not used)
9 V I(fb) input feedback voltage