TPS92010EVM-592: 325mA @ 18V Max, 115V, TRIAC Dim

This EVM uses the TPS92010 high efficiency offline LED lighting driver controller. The power topology is a quasi resonant mode flyback. This makes for a cost competitive solution. This TPS92010 EVM implements a constant current, high efficiency, low ripple AC-DC LED lighting driver.

Current is sensed directly via a resistor and operational-amplifier. This in turn drives an opto-coupler which sets the PWM pulses via the TPS92010 to control the output current at a constant level.

The design also incorporates a circuit to ensure compatibility with a large number of commonly available TRIAC based dimmers. This circuit monitors the line voltage for TRIAC operation. When the TRIAC is operating the line voltage is chopped. This information is used by the circuit to reduce the constant output current level thus dimming the LEDs. It also applies a current path at the input to ensure the TRIAC triggers correctly and maintains triggered condition.