International Rectifier IRS2505L Boost PFC Control IC
International Rectifier's IRS2505L Boost PFC Control IC is the world's first offline AC-DC PFC Boost IC that operates in critical-conduction mode. The device features a novel control system that can implement a PFC controller with only five pins, significantly reducing overall system size, component count and system cost. The IC incorporates a free-running frequency oscillator with on- and off-time control of the boost power MOSFET without the need for a secondary winding. Also included in the design is over-voltage protection of the DC bus and cycle-by-cycle over-current protection of the power MOSFET. Micro-power start-up current and an internal 20.8V zener clamp at VCC are provided to simplify the external VCC supply circuitry. ESD and latch immune CMOS technology enables a rugged monolithic IC construction.