LinkSwitch™-PH single-stage PFC, primary-side constant current control and TRIAC dimming/non-dimming options dramatically simplifies implementation of LED drivers requiring long lifetime, high efficiency, PF <gt/>0.9, and TRIAC dimming capability (LNK403-410). The single-stage combined power factor and constant-current controller eliminates a switching stage and the electrolytic bulk capacitor. The advanced primary-side control used by the LinkSwitch-PH device provides accurate constant current control while eliminating the need for an optocoupler and current sensing circuits. LinkSwitch-PH incorporates a 725V power FET, a continuous mode PWM controller, a high-voltage switched current source for self-biasing, frequency jittering, protection circuitry including cycle-by-cycle current limit and hysteretic thermal shutdown. Meets high voltage creepage requirement between DRAIN and all other signal pins both on PCB and at package. Typically used in off-line LED driver applications.