Critical Conduction Mode Interleaved PFC Control IC
Jul 14, 2010
The R2A20118A controls a boost converter to provide an active power factor correction.
The R2A20118A is based on R2A20117, and additional functions are OVP2 and Brownout.
The R2A20118A 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.
The feedback loop short detection, two modes overvoltage protection and OVP2, overcurrent protection, overcurrent
timer latch protection, and ZCD open detection are built in the R2A20118A, and can constitute a power supply system
of high reliability with few external parts.
Absolute Maximum Ratings
Supply voltage Vcc: 24 V
Operating junction temperature Tjopr: –40 to +150°C
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
Boost converter control with critical conduction mode
Two mode overvoltage protection and OVP2
Mode1: Dynamic OVP corresponding to a voltage rise by dynamic load change
Mode2: Static OVP corresponding to overvoltage in stable.
OVP2: OVP2 sense the PFC output voltage by independenced pin.
Feedback loop short detection
Slave ZCD signal open detection
RAMP charge current selectable function
Master and Slave independenced overcurrent protection
Overcurrent timer latch protection at abnormal operation
280 s restart timer
Soft start function for the reference voltage of Error Amp
Package: Pb-free SOP-20
Taping Abbreviation (Quantity)
W (2,000 pcs/reel)
Jul 14, 2010
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