AS1631

Half bridge Resonant LLC control chip

The AS1631 is a resonant switching power controller based on a half-bridge LLC resonant converter. The chip integrates high-voltage start, AC power failure detection and X capacitor discharge functions to meet the requirements of fast start and ultra-low standby. The AS1631 integrates a half-bridge drive to directly output a 50% duty cycle complementary drive. The chip has a built-in high-precision VCO oscillator with a maximum operating frequency of 350kHz. The chip integrates the function of adaptive dead zone control to ensure the zero voltage on (ZVS) of the power switch tube, which improves the system efficiency. At the same time, the capacitive zone protection function is integrated to avoid the bridge arm straight through and hard switch, which improves the reliability of the system.

In addition, the chip can be controlled into the low standby mode by an external signal, reducing the standby loss of the system. The AS1631 is fully integrated with protection features, including: VDD overvoltage/undervoltage protection (VDD OVP/UVLO), VBT undervoltage protection (VBT UVP), AC overvoltage and input undervoltage protection (LOVP & HV/BR BOP), overload protection (OLP), and resonator overcurrent protection (CBC OCP / SOCP), Output overcurrent protection (OCP), capacitance zone protection, SEL pin short-circuit protection, overheat protection (OTP).

Main feature

• High precision VCO control

• Supports maximum frequency 350kHz

• Integrated 650V half-bridge drive

• Integrated high-voltage start function

• Adaptive dead zone time control

• The soft boot function is configurable

• Integrated AC power failure detection and X capacitor discharge

• Support PFC-free design applications

• Normal working mode or low standby mode can be configured

• Encapsulation type SOP-16

• Integrated protection features:

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

• VBT Undervoltage Protection (VBT UVP)

• HV pin input Undervoltage protection (HV BOP)

• BR pin configurable input Undervoltage protection (BR BOP)

• AC Overvoltage Protection (LOVP)

• Overload Protection (OLP)

• Cavity current Cyclic overcurrent protection (CBC OCP)

• Output Overcurrent Protection (OCP)

• Capacitive area protection

• SEL pin open short circuit protection

• Overheat protection (OTP)

Typical application

• TV board card power supply

• LED Applications

• Adapter power supply

• Open, server and other switching power supply