The UCC3818 functions as an active power factor-corrected pre-regulator. The controller achieves a 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.

It is designed by Texas Instruments using the BiCMOS technology. The BiCMOS technology combines the strengths of two different process technologies into a single chip: Bipolar transistors offer high speed and gain, which are critical for high-frequency analog sections, whereas CMOS technology excels in constructing simple, low-power logic gates.