The triac dimming method is widely used in the LED lighting industry. What are the following factors for the flicker of LED lamps caused by the triac dimming:

1. Caused by rush current

Because the triac front-cutting chopper keeps the input voltage at the peak position, the input filter capacitor will receive a larger inrush current at this time, which can cause the thyristor to be cut off, causing the thyristor to restart continuously.

Second, caused by the holding current of the triac

At present, the power levels of triac dimmers on the market are different. If the conduction is small, it may also cause the LED lights to flicker. Therefore, the input voltage and current source are relatively small, which may cause the current to fail or the chip The power supply is not working, the circuit stops working, etc., which causes the LED lights to flicker.

Third, caused by impedance matching problems

When the triac is turned on, the impedance of the triac and the drive circuit will occur, and the triac driver circuit may have impedance matching problems with the triac dimmer due to the existence of differential aluminum wave capacitors. Therefore, it is generally better to use a smaller differential filter capacitor in the planning circuit.