Diodes – AP3301 – Quasi-Resonant PWM Controller Provides High Efficiency Across all Loads
AP3301 is a peak-current control Quasi-Resonant (QR) PWM controller optimized for high performance, low standby power and cost-effective offline flyback power supplies.
The AP3301 has multiple modes of operation to minimize power losses dependent on load.
1. Fixed frequency CCM PWM: With heavy or increasing output loads the AP3301 operates in Continuous Conduction (CCM) Mode with a fixed switching frequency of 62kHz; this optimizes power conversion efficiency.
2. QR mode: At medium loads, AP3301 enters valley lock QR mode with frequency fold-back to improve system efficiency and EMI performance. The maximum switching frequency (about 120kHz) is set to clamp the QR frequency to improve efficiency.
3. Burst Mode: At no- or light-load, AP3301 enters burst mode to minimize standby power consumption. The minimum switching frequency (about 20kHz) is set to avoid audible noise.
The AP3301 includes comprehensive protection features such as cycle-by-cycle current limit (OCP), VCC Overoltage Protection (VOVP), internal Overtemperature Protection (OTP) and Overload Protection (OLP).
AP3301 has additional output overvoltage protection (SOVP) and Brown-out protection (BNO) to enhance system reliability.
The Diodes Advantage
AP3301 is a high-performance, and cost-effective AC-DC solution for portable consumer applications which need to pass DOE6/COC Tier2.
- Multiple Modes of Operation: 62kHz CCM PWM Mode, QR-Mode and Burst Mode Optimizes efficiency across all load levels
- Active Frequency Dithering in 62kHz CCM PWM and QR modes Reduces EMI emission
- Adjustable OCP Line Compensation Making OCP balance more flexible
- Overcurrent Protection, VCC Overvoltage Protection, Internal Overtemperature Protection, Overload Protection Increases system reliability and robustness
- Output Overvoltage Protection (SOVP) Precise output OVP protection which improves the OVP performance
- AC Input Brown-Out Protection(BNO) BNO protects system from damage due to ultra low line condition
Applications
- Switching AC-DC adapter
- ATX/BTX auxiliary power
- Set-Top Box (STB) power supply
- Open-frame switching power supply
Link to the Datasheet
