Datasheet tca-785
Phase Control IC
TCA 785
Bipolar IC
Features q q q q q q q q
Reliable recognition of zero passage Large application scope May be used as zero point switch LSL compatible Three-phase operation possible (3 ICs) Output current 250 mA Large ramp current range Wide temperature range
P-DIP-16-1
Type TCA 785
Ordering Code Q67000-A2321
Package P-DIP-16-1
This phase control IC is intended to control thyristors, triacs, and transistors. The trigger pulses can be shifted within a phase angle between 0 ˚ and 180 ˚. Typical applications include converter circuits, AC controllers and three-phase current controllers. This IC replaces the previous types TCA 780 and TCA 780 D. Pin Definitions and Functions Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 Pin Configuration (top view) Semiconductor Group 14 15 16 1 Symbol GND Q2 QU Q2 VSYNC I QZ V REF R9 C10 V11 C12 L Q1 Q2 VS Function Ground Output 2 inverted Output U Output 1 inverted Synchronous voltage Inhibit Output Z Stabilized voltage Ramp resistance Ramp capacitance Control voltage Pulse extension Long pulse Output 1 Output 2 Supply voltage 09.94
TCA 785
Functional Description The synchronization signal is obtained via a high-ohmic resistance from the line voltage (voltage V5). A zero voltage detector evaluates the zero passages and transfers them to the synchronization register. This synchronization register controls a ramp generator, the capacitor C10 of which is charged by a constant current (determined by R9). If the ramp voltage V10 exceeds the control voltage V11 (triggering angle ϕ), a signal is processed to the logic. Dependent on the magnitude of the control voltage V11, the triggering angle ϕ can be shifted within a phase angle of 0˚ to 180˚. For every half wave, a positive pulse of approx. 30 µs duration appears at the outputs Q 1 and Q 2. The pulse duration can be prolonged up to 180˚ via a capacitor C12. If pin 12 is connected to ground, pulses with a duration between ϕ and 180˚ will