AS6A31N

Dual phase interleaved parallel, critical on-mode boost power factor correction controller

The AS6A31N is a two-phase Interleaved, critical on-mode Boost (CRM Boost) constant voltage power factor correction (PFC) controller. The double-phase staggered parallel structure reduces the current stress of each phase, disperses the thermal stress, and reduces the volume of inductance, thus facilitating the system design. The integrated dual-phase interleave clock control logic in the chip can reliably realize the 180° phase difference between the two channels in all working conditions, the input and output current ripple is significantly reduced, and the ripple frequency is doubled, effectively reducing the size of the EMI filter, improving system reliability and reducing the output capacitance capacity requirements. The AS6A31N controlled two-phase circuit can work adaptively in both critical on-mode (CRM) and discontinuous on-mode (DCM).

Full load when the chip works in CRM; The load is reduced when the chip works in DCM to improve system efficiency. The chip can also achieve high power factor (PF) and low input harmonics (THD) performance easily by optimizing the CRM/DCM control algorithm and input line voltage feedforward. In addition, the chip further improves the light-load efficiency through the Burst mode and greatly reduces the standby loss of the system. The AS6A31N is fully integrated with protection features, including: VDD Undervoltage protection (UVLO), VDD Overvoltage protection (VDD OVP), Input Undervoltage protection (BOP), Output Undervoltage protection (UVP), Output Overvoltage protection (OVP), Cycle by Cycle Current Limit (OCP), Enable In-rush Current detection, overheat protection (OTP), and pin open short-circuit protection.

Main features:

• Two-phase interleaved parallel, critical on-mode (CRM)

• All operating conditions, reliable 180° phase shift control technology

• Light load efficiency optimization and standby loss optimization

• Power factor >0.95

• Light load THD optimization, THD<10%

• Dynamic performance optimization

• Adjustable maximum output power

• Auxiliary winding to achieve degaussing detection

• Accurate valley floor conduction

• Internal protection functions:

• VDD overvoltage/Undervoltage protection (VDD OVP/UVLO)

• Input Undervoltage Protection (BOP)

• Output overvoltage/undervoltage protection (OVP/UVP)

• Initiate In-rush Current detection (IN-rush Current)

• Cycle Current Limit (OCP)

• Overheat protection (OTP)

• Pin open short circuit protection

• Encapsulation type SOP-16