Full Bridge Current Driver Vertical Deflection Booster - NEC MultiSync V520 Service Manual

6.

Full bridge current driver vertical deflection booster

TDA4866
1. Fully built-in type construction, with practically no external component.
2. High-grade amplification of the linear sawtooth wave signal.
3. High-efficiency DC coupling vertical bridge circuit.
4. Powerless vertical shift
5. Deflection frequencies up to 140 Hz
6. The power consumption and fly-back time can be optimized, because the power supply voltage
and the fly-back voltage can be individually adjusted.
7. Superior transition movement during the fly-back.
8. Guard circuit provided for screen protection.
Function Description
1) Differential input stage
Since the differential input stage is provided with high-grade CMRR differential current input (Pins 1/
2) system, the magnetic resistance is high, and is optimum for driver units with differential signals
and single–ended current signals.
2) Output stage
The two output stages are current-driven type ones with opposite phases, and are operated in
combination with the deflection coil that has full-bridge construction.
3) Fly-back generator
During fly-back, the fly-back generator supplies the fly-back voltage to the output stage A.
4) Protection unit
The output stage is provided with protection units against overheating and short-circuit of the coil
(Pins 4/6).
5) Guard circuit
The built-in guard circuit supplies the fly-back line erasing signal to the CRT, and the guard signal
is active.
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