Special triac-driving ICs are available to 'gate' triacs through zero-crossing method. These ICs "have an inbuilt AC 'rirc.,tifier:circuit, zero-crossing detector, gating circuit and high-gain differential amplifier in a single package. C93059 and TDA102 belong to this category.

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When pin 13 of the IC is biased through Sl, the triac is triggered through the zero-crossing method provided pin 13 is biased above pin 9. The internal differential amplifier of the IC enables the gate of the triac through output pin 4.