The HF600-40 is a highly integrated, multi-mode flyback regulator that is suitable for high-performance and high-efficiency designs. The device adopts continuous conduction mode (CCM) or quasi-resonant (QR) mode. Unlike conventional QR flyback regulators, the HF600-40 provides frequency foldback to guarantee high efficiency across the entire load range.

The HF600-40 is a secondary-side regulation (SSR)-based primary regulator, which must work with secondary-side feedback circuitry. The device integrates high-voltage start-up circuits with an ultra-low quiescent current (I_Q) in burst mode. As a result, power consumption under no load can be below 30mW.

The HF600-40 adopts the patented valley lock technique to restrain valley jumping from one to the other during operation, which can prevent audible noise. The device also adopts various pulse-frequency modulation (PFM) modes based on the input voltage (V_IN), which can significantly enhance the output power (P_OUT) capacity for wide input applications.

The HF600-40 features advanced protections, including primary-sense output over-voltage protection (ZCD OVP), primary-sense output under-voltage protection (ZCD UVP), VCC over-voltage protection (VCC OVP), output overload protection (OLP), internal brown-in (B/I), short-circuit protection (SCP), current-sensing short/open protection (SSP/SOP), internal thermal shutdown (OTP), and under-voltage lockout (UVLO).

The HF600-40 is available in a PDIP8-7B package.