Triacs: How to calculate power and predict Tjmax

Focus:

Instructions are given for calculating the power dissipation and maximum junction temperature of triacs and silicon-controlled rectifiers as well as the thermal resistance required for their heatsinks. These calculations are demonstrated in four design examples---1) a vacuum cleaner that uses a triac in a phase control circuit to control its motor speed 2) a refrigerator compressor that uses a triac in an electronic thermostat to control its on-off switching 3) a top-loading washing machine with two triacs that control a reversing induction motor 4) an electric drill with an SCR in a half-wave phase control circuit that controls the speed of a universal (brush) motor.

What you’ll learn:

• How to calculate the power dissipation of Triacs and SCRs

Notes:

NXP Application Note AN10384

View the Source

Author & Publication:

no author listed, NXP, Vendor website, Aug 10 2005

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