The HF01B04 is a flyback regulator with Green Mode Operation. Its high efficiency feature over the entire input/load range meets the stringent world-wide energy-saving requirements. The HF01B04 is an integrated current mode controller with a 700V FET. Its valley switching detector ensures minimum Drain-Source voltage switching every cycle, per Quasi-resonant operation. When the output power falls below a given level, the regulator enters the burst mode to lower the stand-by power consumption. An internal minimum off time limiter prevents the switching frequency from exceeding 150 kHz, which is below the CISPR-22 EMI start limit. Internal 2.4ms soft start prevents the excessive inrush current during start up The HF01B04 provides various protections, such as Thermal Shutdown (TSD), VCC Under Voltage Lockout (UVLO), Over Load Protection (OLP), Over Voltage Protection (OVP) and so on. HF01B04 is available in PDIP8-7B and SOIC8-7B packages.