The R2A20112 is an active power factorcorrection controller thatoperates in the criticalconduction mode (CRM). And the R2A20112 has the interleaved operation function that controls two boost converters of the master and the slave with 180 degree phase shift.
The 2A20112 is the voltage mode CRM that a Power MOSFET is turned on when the current of the boost inductor reaches zero and turned off by comparing of a ramp slope and an output voltage of the error amplifier. The Power MOSFET switch turn on time is controlled to be constant.
Because turn on time is constant, the peak current of the boost inductor follows the input voltage waveform. The voltage mode CRM PFC controller does not need the input voltage sense line. It can reduce power loss. The master boost converter is controlled by the above voltage mode CRM, and the slave boost converter is controlled by the internal slave control logic and the inductor zero current detection. The interleaved operation can reduce the input current ripple, therefore it reduce an input filter capability, parts count and total cost.
Other data sheets within the file : 2A20112, R2A20112, R2A20112SPW0, R2A20112DDU0