UCC3819A

The UCC2819A/UCC3819A provides all the functions necessary for active power factor corrected preregulators. The controller achieves near unity power factor by shaping the ac-input line current waveform to correspond to that of the ac-input line voltage. Average current mode control maintains stable, low distortion sinusoidal line current.

Designed in Texas Instrument’s BiCMOS process, the UCC3819A offers new features such as lower start-up current, lower power dissipation, overvoltage protection, a shunt UVLO detect circuitry and a leading-edge modulation technique to reduce ripple current in the bulk capacitor.

The UCC3819A allows the output voltage to be programmed by bringing out the error amplifier noninverting input.

The UCC3819A is directly pin for pin compatible with the UCC3819. Only the output stage of UCC3819A has been modified to allow use of a smaller external gate drive resistor values. For some power supply designs where an adequately high enough gate drive resistor can not be used, the UCC3819A offers a more robust output stage at the cost of increasing the internal gate resistances. The gate drive of the UCC3819A remains strong at ±1.2 A of peak current capability.

Available in the 16-pin D, N, and PW packages.