Rolsen 21C19/PF21C19, Service Manual

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SERVICE MANUAL
26
1.4 Vertical scan output stage circuit TDA8356/N6
DC-coupled vertical deflection circuit TDA8356
1) Features
●
Few external components
● Highly efficient fully DC-coupled vertical output bridge circuit
●
Vertical flyback switch
●
Guard circuit
●
Protection against:
Short-circuit of the output pins (7 and 4)
Short-circuit of the output pins to VP.
●
Temperature protection
●
High EMC immunity because of common mode inputs
●
A guard signal in zoom mode.
2) General Description
The TDA8356 is a power circuit for use in 90, and 110, colour deflection systems for field frequencies of
50 to 120 Hz. The circuit provides a DC driven vertical deflection output circuit, operating as a highly
efficient class G system.
3) Block Diagra 4) Pinning
Fig.13 Fig.14
SYMBOL PIN DESCRIPTION
Idrive(pos) 1 input power-stage (positive); includes II(sb) signal bias
Idrive(neg) 2 input power-stage (negative); includes II(sb) signal bias
VP 3 operating supply voltage
VO(B) 4 output voltage B
GND 5 ground
VFB 6 input flyback supply voltage
VO(A) 7 output voltage A
VO(guard) 8 guard output voltage
VI(fb) 9 input feedback voltage