DESCRIPTION The TK83854 family of integrated circuits provide active power factor correction for power systems that otherwise would draw non-sinusoidal current from sinusoidal power lines. These parts implement all the control functions necessary to build a power supply preregulator capable of optimally using available power-line current while minimizing line-current distortion. To do this, the TK83854 contains a voltage amplifier, a precision analog multiplier/divider, a current amplifier, and a fixed-frequency PWM. In addition, the TK83854 contains a power MOSFET gate driver, 7.5 V reference, line anticipator, load-enable comparator, low supply detector, and overcurrent comparator. FEATURES ■ Control Boost PWM to 0.99 Power Factor ■ Limit Line Current Distortion to < 5% ■ Worldwide Operation without Switches ■ Feed-Forward Line Regulation ■ Low Noise Sensitivity ■ Pin Compatible with UC2854, and UC3854 (Licensed Source) ■ Low Start-Up Supply Current ■ Fixed-Frequency PWM Drive ■ Low-Offset Analog Multiplier/Divider ■ 1 Amp Totem-Pole Gate Driver ■ Precision Voltage Reference
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