AS2780

High PF, low THD, primary side control quasi-resonant flyback constant voltage controller

The AS2780 is a constant voltage output controller with high power factor, low total harmonic distortion, and primary side control. The chip has a built-in high-voltage start circuit, which can meet the requirements of fast start and ultra-low standby.

AS2780 adopts quasi-resonant working mode, the system has high working efficiency, but also can obtain better EMC performance. The chip can set the lowest operating frequency, which can ensure that the output voltage of the system does not drift under light pseudo load conditions, and meet the requirements of low standby loss.

KP2813 built-in adaptive output voltage limiting mechanism, speed up load dynamic response to meet different application needs. The AS2780 is fully integrated with protection features, including: VDD Undervoltage protection (VDD UVLO), VDD Overvoltage protection (VDD OVP), input Undervoltage protection (BOP), output Overvoltage protection (OVP), output Undervoltage protection (UVP), cycle current Limit (OCP), Abnormal Overcurrent protection (AOCP), overload protection (OLP), short circuit protection (SCP), built-in overheat protection (OTP), front blanking (LEB), etc.

Main feature

• High efficiency in quasi-resonant mode

• Full voltage power factor >0.95, THD<10%

• The graded harmonics meet IEC61000-3-2 Class C

• Built-in fast soft start, system startup time <500ms

• Output constant pressure accuracy ±3%

• Integrated 650V high voltage start and power supply circuit

• Ultra-low starting and operating current, standby power consumption <50mW

• Encapsulation type SOP-8

• Integrated protection features:

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

• Output Overvoltage protection (OVP)

• Input Undervoltage Protection (BOP)

• Overheat protection (OTP)

• Weekly Term Current protection (OCP/AOCP)

• Output Short-circuit Protection (SCP)

• Overload Protection (OLP)

• Front blanking (LEB)

Typical application

• Intelligent lighting, landscape lighting

• Constant voltage external power supply