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 and slave ZCD open detection are built in the R2A20112A, and can constitute a power supply system of high reliability with few external parts.

Features
• Absolute Maximum Ratings
   ⎯ Supply voltage Vcc: 24 V
   ⎯ Junction temperature Tj: –40 to +150°C
• Electrical Characteristics
   ⎯ VREF output voltage Vref: 5.0 V ± 1.5%
   ⎯ UVLO operation start voltage Vuvlh: 10.5 V ± 0.7 V
   ⎯ UVLO operation shutdown voltage Vuvll: 9.3 V ± 0.5 V
   ⎯ UVLO hysteresis voltage Hysuvl: 1.2 V ± 0.5 V
• Functions
   ⎯ Boost converter control with critical conduction mode
   ⎯ Interleaving control
   ⎯ Soft start function for the reference voltage of Error Amp
   ⎯ Two mode PFC output Over-voltage-protection
      Mode1: Dynamic OVP corresponding to a voltage rise by dynamic load change.
      Mode2: Static OVP corresponding to over-voltage in stable.
   ⎯ PFC output Dynamic-under-voltage-protection (DUVP)
   ⎯ Feedback loop open/short detection
   ⎯ Master and Slave independence over-current-protection
   ⎯ 280 μs restart timer
   ⎯ Slave ZCD signal open detection
   ⎯ Over current ON/OFF timer protection for boost Diode short
• Package
   ⎯ Pb-free SOP-16