LED driver with single inverter circuit with isolated multi-channel output

摘要

A single-converter circuit-based LED driver circuit (10) with isolated multi-channel outputs is disclosed. The circuit (10) includes an IC control circuit (11), a plurality of isolated output channels (70, 74) each having an output current sensing and conditioning circuit (74, 90), and an output current regulation circuit (128). The output current regulation circuit (128) includes a voltage-sensing transformer winding (T4) that senses an output voltage level across a secondary side of the circuit (10), and a peak output current sensing component (156) that senses output currents from the isolated output channels and determines which channel has a highest current output. Additionally, the circuit (10) facilitates providing output current regulation when detected output voltage is below a predetermined threshold, and providing output current regulation when the detected output voltage is above the predetermined threshold.