The HF500-40 is a fixed-frequency, current-mode regulator with built-in slope compensation. The HF500-40 combines a 700V MOSFET and a full-featured controller into one chip for a low-power, offline, flyback, switch-mode power supply.
At medium and heavy loads, the regulator works in a fixed frequency with frequency jittering. Jittering helps reduce EMI energy on the switching frequency and its harmonics. During light-load condition, the regulator freezes the peak current and reduces its switching frequency to 25kHz to offer excellent efficiency. At very light loads, the regulator enters burst mode to achieve low standby power consumption.
Full protection features include brown-in and brown-out, VCC under-voltage lockout (UVLO), overload protection (OLP), short-circuit protection (SCP), input over-voltage protection (OVP), VCC over-voltage protection (OVP), and over-temperature protection (OTP).
The HF500-40 features over-power line compensation to ensure that the overload protection point is independent of the input voltage.
The HF500-40 is available in a PDIP8-7B package.
Fully featured controller in one chip for a low-power, offline, flyback, switch-mode power supply
Multi-mode control during different load conditions
Over-power line compensation and full suite of protection features