Single-stage PWM controller for PFC and phase-cut dimmable LED driving

Fairchild's FL7734, a highly-integrated PWM controller is now available from Digi-Key. The device benefits from advanced primary-side-regulation (PSR) technology to minimize components for low-power LED lighting solutions. Using innovative Truecurrent technology for tight constant-current control, it enables designs with constant-current (CC) tolerance of less than ±1% in the wide line voltage range to meet stringent LED brightness requirements. The FL7734 can operate with all types of phase cut dimmers. Phase cut dimming is managed smoothly by bleeding current control to achieve 'excellent dimmer compatibility without flicker'. The controller can automatically detect whether there is a dimmer connection. In non-dimming mode, the operating mode is set to optimize power factor and THD by enabling linear frequency control and voltage mode based on DCM, says the company.