Controls Boost Preregulator to Near-Unity

Power Factor

World Wide Line Operation

Over-Voltage Protection

Accurate Power Limiting

Average Current Mode Control

Improved Noise Immunity

Improved Feed-Forward Line Regulation

Leading Edge Modulation

150-μA Typical Start-Up Current

Low-Power BiCMOS Operation

10.8-V to 17-V Operation

Programmable Output Voltage (Tracking

Boost Topology)

description

The UCC2819/UCC3819 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 UCC3819 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 UCC3819 allows the output voltage to be programmed by bringing out the error amplifier noninverting input.

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