• Integrated E-Mode GaN Drive
• QR/DCM Operating Modes
• Soft GaN Gate Drive for Optimized EMI Performance
• Wide VCC Operating Range: 7-85V
• Switching Frequency Range: 25kHz–500kHz
• Frequency Modulation to Reduce EMI Noise
• Integrated 700V HV Startup Circuitry
• Programmable Output OVP and UVP
• Programmable Brown-In/Out Protection
• Programmable AC input OVP
• Current Sense Resistor Short-Circuit Protection
• Winding or SR Short-Circuit Protection
• Internal and External OTP
• Compact Package: SSOP9

The SY5023C is a high frequency flyback controller operating in quasi-resonant (QR) mode. It integrates high voltage (HV) start up block for smaller no load loss. It can drive enhancement-mode (E-mode) GaN FET directly. The device is designed for power delivery (PD) capable adapters and quick chargers. Its maximum operating frequency of up to 500kHz allows for reduced transformer, PCB, and capacitor sizes.

The SY5023C operates using peak current control. At heavy load the device enables QR mode. In this mode, the GaN FET turns on at the valley point to minimize switching losses. As the load decreases, the SY5023C enters DCM mode to lower the switching frequency and improve efficiency. Under very light load conditions, the device enters burst mode to further reduce power loss.

The SY5023C integrates comprehensive protection features to ensure reliable operation, including HV startup, brown-out protection, output and VCC overvoltage protection (OVP), output undervoltage protection (UVP), internal and external overtemperature protection (OTP), and open-loop protection (OLP).

It is recommended to use the SY5236 or SY5236A as a secondary-side synchronous rectifier (SR) controller in conjunction with the SY5023C to enable zero voltage switching (ZVS) at high input voltage for efficiency.

The SY5023C is available in a compact SSOP9 package.