The FA3641P(N) and FA3647P(N) are the PWM type switching power supply control ICs that can directly drive power MOSFET. These ICs use a CMOS device with high dielectric strength (30V) to implement low power consumption. They feature a number of functions that are equivalent to those of the FA531X series consisting of bipolar devices. In addition, they have a function that reduces the oscillation frequency to suppress loss of the power supply in light load mode and support an overvoltage protection detecting Vcc voltage. These ICs are most suitable for high-performance, energy-saving power supplies that require low input power in standby or no-load mode.