MT9526SF is a high-PF, non-Isolated APFC Buck IC for LED driver with integrated rectifier bridge and ultra-fast recovery freewheeling diode. MT9526SF works in Quasi-Resonant Mode (QRM), which improves both of efficiency and EMI performance. 

MT9526SF integrates the ultra-high voltage power supply circuit and the external VDD capacitor is not needed. The system realizes error integration through internal digital integrator, which eliminates COMP pin and COMP capacitor. MT9526SF can meet low THD and odd harmonic requirements through internal THD compensation circuit. 

MT9526SF provides various protections with self-recovery, such as input over-voltage protection (OVP), cycle-by-cycle over-current protection (OCP), over-temperature regulation (OTR), output short-circuit protection, output open-circuit protection, etc., to improve reliability. 

MT9526SF integrates rectifier bridge, freewheeling diode, feedback circuit, CS resistor and high voltage MOS, which further simplifies external circuit and saves the BOM cost. 

• Single-stage active power factor correction (PF > 0.90) 

• Integrates rectifier bridge 

• Internal ultra-fast recovery freewheeling diode 

• Integrates ultra-high voltage power supply without external VDD capacitor and external power supply circuit 

• Embedded with digital integrator, no COMP capacitor needed 

• No external CS resistor 

• Integrates THD compensation circuit 

• Integrates odd harmonic compensation circuit for high subharmonic distortion suppression 

• Internal line voltage compensation 

• Internal demagnetization sensing, no external feedback circuit needed 

• High accurate LED current 

• Output current foldback at low input voltage 

• Good line and load regulation 

• Operates in QRM 

• Integrates input OVP, when input voltage is higher than 400Vac, turns off the power switch, resumes at input voltage below 320Vac. Enhances anti-surge capability and improves system reliability 

• Various protections with self-recovery 

• Power on soft-start 

• Available in ASOP7 package