Diodes Incorporated AP3128 PWM Controller
Diodes Incorporated AP3128 PWM Controller is a peak-current control and multi-mode (QR+CCM) PWM controller. This controller is optimized for high performance, low standby power, and cost-effective offline flyback converters. The AP3128 controller is designed to enter burst mode at no-load/light-load and minimizes standby power consumption. This controller features a 105kHz maximum switching frequency that clamps the QR frequency to reduce switching power loss and the minimum frequency avoids audible noise. The AP3128 controller offers multi-mode control, soft start during the startup process, frequency foldback for high average efficiency, and secondary winding short protection with FOCP. Typical applications include a cell phone charger, Power Delivery (PD) application, ATX/BTX auxiliary power, Set-Top Box (STB) power supply, and open frame switching power supply.
Features
- Multi-mode control
- Quasi-Resonant (QR) operation at high line voltage
- Continuous Current Mode (CCM) operation at low line voltage
- Non-audible noise quasi-resonant control
- Soft start during the startup process
- Frequency fold back for high average efficiency
- Constant Over Current Protection (OCP)
- Secondary winding short protection with FOCP
- Frequency dithering for reducing EMI
- Useful Pin fault protection:
- SENSE pin floating
- FB/optocoupler open/short
- Comprehensive system protection feature:
- VCC Overvoltage Protection (VOVP)
- Overload Protection (OLP)
- Brown Out Protection (BNO)
Specifications
- 10V to 50V supply voltage range
- -40°C to 150°C operating junction temperature range
- 80kHz (CCM mode) oscillation frequency
- 1µA startup current
- -800mA to 300mA output current range
- 550mW Power Dissipation (PD) at TA < 25°C
Applications
- Cell phone charger
- Power Delivery (PD) application
- ATX/BTX auxiliary power
- Set-Top Box (STB) power supply
- Open frame switching power supply
Block Diagram
Typical Application Circuit
Published: 2021-11-08
| Updated: 2022-03-11