The TDA1770A is a monolithic integrated circuit in a 20‑lead plastic package that provides a complete vertical deflection circuit for CRT displays. It integrates a precision oscillator, ramp generator, power output amplifier, flyback generator, voltage regulator, blanking pulse generator and thermal shutdown protection.
The document lists absolute maximum ratings, DC and AC electrical characteristics, typical application circuits for TV sets, performance parameters such as supply voltage, current, flyback time and thermal data, as well as mounting instructions for heatsink design.
| Supply Voltage (Pin 2) max | 35 V |
|---|---|
| Flyback Peak Voltage | 60 V |
| Output Peak Current (50 Hz, >10 µs) | 12 A |
| Thermal Resistance Junction‑pins | 14 °C/W |
| Minimum Supply Voltage | 25 V |
| Supply Current | 140 mA |
| Flyback Time | 0.7 ms |
| Blanking Time | 1.4 ms |
| Free Running Frequency | 43.5 Hz |
| Total Power Dissipation (typical) | 24 W |
The maximum supply voltage at Pin 2 is 35 V.
The typical free‑running frequency is 43.5 Hz.
By soldering the ground pins to a suitable copper area on the PCB or to an external heatsink, the junction‑to‑ambient thermal resistance can be lowered.