Application Note AN6012 Design of Power Factor Correction Circuit Using FAN7528
The document describes the FAN7528, an active power factor correction (PFC) controller designed for boost PFC applications operating in critical conduction mode (CRM). It operates in voltage mode, eliminating the need for a rectified AC line voltage sensing network to save power. The controller features a dual output control function that adjusts the internal reference voltage based on the AC line voltage range (100Vac or 220Vac) without direct sensing, optimizing output voltage for low and high line conditions.
| Operating Mode | Critical Conduction Mode (CRM) |
|---|---|
| Control Mode | Voltage Mode |
| Low Line Reference Voltage | 1.5V |
| High Line Reference Voltage | 2.5V |
| Output Voltage (Low Line) | 240V |
| OVP Voltage (High Line) | 426V |
| Drive Output Peak Current | 400mA |
| Drive Output Rise/Fall Time | 50ns |
| OCP Threshold | 0.8V |
The FAN7528 operates in the critical conduction mode (CRM).
No, the voltage mode CRM PFC controller does not need the rectified AC line voltage information.
The internal reference voltage is set to 1.5V for low line condition and 2.5V for high line condition.