The UCC2818D is a BiCMOS Power Factor Preregulator designed to 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. It offers new features such as lower start-up current, lower power dissipation, overvoltage protection, a shunt UVLO detect circuitry, a leading-edge modulation technique to reduce ripple current in the bulk capacitor and an improved, low-offset (±2mV) current amplifier to reduce distortion at light load conditions. Also offers an on-chip shunt regulator with low start-up current.
Controls boost preregulator to near-unity power factor
Limits line distortion
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
150µA Typical start-up current
Green product and no Sb/Br
Device has limited built-in ESD protection, leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.