Description: The R2A20112A controls a boost converter to provide an active power factor correction. The R2A20112A adopts critical conduction mode for power factor correction and realizes high efficiency and a low switching noise by zero current switching. Interleaving function improves ripple current on input or output capacitor by 180 degrees phase shift. Soft-star, the feedback loop short detection, two mode over-voltage-protection, over-current-protection, Over current ON/OFF timer protection for boost Diode short an