The HA16141P/FP and the HA16142P/FP are power supply controller ICs combining an AC-DC converter switching controllers for power factor correction and off-line power supply switching controllers. PFC (Power factor correction) section employs average current mode PWM and off-line power supply control section employs peak current mode PWM. The HA16142P/FP is the change version of HA16141P/FP's PWM maximum on duty cycle. The PFC operation can be turned on and off by external control signal. Use of this on/off function makes it possible to disable PFC operation at a low line voltage, or to perform remote control operation from the transformer secondary side. The PFC power supply boosted output voltage is not only fed to an error amplifier input signal but also fed to as the boost voltage monitor circuit. PG signal is put out if the boost voltage is out-of-spec.