PIN DETAIL of IC A255D
Substitute : TDA2590,TDA2591,TDA2593
Function :
1.sync separator
2.Vertical sync separator
3.AFC
4.Horizontal sync separator
5.Burst gating and Horizontal blanking pulse generator
Pin No. | Function | Voltage |
1. | Positive (+ Ve supply voltage) | 12 |
2. | Positive (+ Ve supply voltage) for output stage (Trigger pulse input) | 12 |
3. | Horizontal trigger pulse output (15625Hz) | 1.2 |
4. | Selection of output pulse duration | 0 |
5. | Decoupling capacitor | 0 |
6. | Horizontal flyback (blanking)pulse(15625Hz) | 1.8 |
7. | Sandcastle (Horizontal blanking pulse )output(15625 Hz) | 1.8 |
8. | Vertical sync input | 0.2 |
9. | Sync pulse input | 1.6 |
10. | Noise separator input | 2.2 |
11. | VCR Switching (Coincidence) | 5.7 |
12. | Time constant switching (third phase comparator) | 2.2 |
13. | First phase comparator output | 6.1 |
14. | Ramp (sawtooth) oscillator capacitance | 6 |
15. | Horizontal frequency (15625Hz) adjust (H-Hold) | 6 |
16. | Ground( -Ve supply voltage ) | 0 |
