FAN7930C PFC Controller in Critical Conduction Mode.

. . FAN7930C is an active power factor correction (PFC) controller designed for boost PFC applications, operating in critical conduction mode (CRM). It uses PWM in voltage mode, comparing the internal ramp signal with the output of an error amplifier to generate a signal to turn off the MOSFET. Since the PFC CRM controller in voltage mode does not require rectified AC line voltage information, it saves the loss of input voltage sensor network power, which is necessary for the PFC CRM controller in current mode.The FAN7930C provides overvoltage protection (OVP), open-circuit feedback protection, overload protection (OCP), input voltage miss detection and under-voltage lockout (UVLO). The PFC-ready pin can be used to trigger other power stages when the PFC output voltage reaches the appropriate level with hysteresis.The FAN7930C can be turned off if the INV pin voltage is lower than 0.45V and the operating current drops to a very low level. Thanks to the new variable duration control method, THD is lower than that of conventional CRM boost PFC circuits. FAN7930C's THD is lower than that of conventional CRM boost PFC circuits. PFC readiness signal. Input voltage failure detection. Maximum switching frequency limitation. Internal soft start and startup without overshoot. Internal harmonic total distortion (THD) optimizer. Precise output overvoltage protection control. Open feedback protection and deactivation function. Zero current detector (ZCD). Internal 150 μs start-up timer. MOSFET overload protection (OCP). Low voltage lock with 3.5V hysteresis. Low inrush and operating current. Totem-pole output with high state clamp. +500/-800mA peak gate control current. 8-pin SOP design. Applications: Power supply. Ballast. LCD TV, CRT TV. SMPS (power source for inverters).