AP3125CM (Not Recommended for new design)

Description

The AP3125CM is a current mode PWM controller which is optimized for high performance, low standby power and cost effective offline flyback converters.

The PWM switching frequency at normal operation is internally fixed (about 65kHz). In no load or light load, the IC will enter the burst mode to minimize standby power. Furthermore, the frequency dithering function is built-in to reduce EMI emission.

Internal slope compensation allows more stable Peak-Current Mode control over wide range of input voltage and load conditions. Internal line compensation ensures constant output power limit over entire universal line voltage range.

Comprehensive protection features are included, such as cycle-bycycle current limit (OCP), V_CC Overvoltage Protection (VOVP), internal OTP, Overload Protection (OLP) and pins’ fault protection. AP3125CM combines secondary side OVP (SOVP) and external OTP.

Feature(s)

• Very Low Start-up Current
• Current Mode Control
• Internal Slope Compensation
• Soft-Start During Startup Process
• Secondary Winding Short Protection with FOCP
• Soft Switching for Reducing EMI
• V_CC Maintain Mode
• Useful Pin Fault Protection:
  
  • SENSE Pin Floating
  • FB/Opto-coupler Open/Short
• Comprehensive System Protection Feature:
  
  • V_CC Overvoltage Protection (VOVP)
  • Overload Protection (OLP)
  • Secondary Side OVP (SOVP) and External OTP
• Mini Size Package of SOT26
• Totally Lead-free & Fully RoHS Compliant
• Halogen and Antimony Free. “Green” Device

Application(s)

• Switching AC-DC Adapter/Charger
• ATX/BTX Auxiliary Power
• Set-top Box (STB) Power Supply
• Open Frame Switching Power Supply