UC3854 Datasheet | Texas Instruments

Product Folder Order Now Technical Documents Tools & Software Support & munity UC1854, UC2854, UC3854 SLUS336A - JUNE 1998 - REVISED DECEMBER 2016 UCx854 High-Power Factor Preregulator 1 Features - 1 Control Boost PWM to 0.99 Power Factor - Limit Line-Current Distortion to < 5% - World-Wide Operation Without Switches - Feedforward Line Regulation - Average Current-Mode Control - Low Noise Sensitivity - Low Startup Supply Current - Fixed-Frequency PWM Drive - Low-Offset Analog Multiplier and Divider - 1-A Totem-Pole Gate Driver - Precision Voltage Reference 2 Applications - Offline AC-to-DC Converters - Medical, Industrial, Tele, and IT Power Supplies - Uninterruptible Power Supplies (UPS) - Appliances and White Goods 3 Description The UC1854 provides active-power factor correction for power systems that otherwise would draw nonsinusoidal current from sinusoidal power lines. This device implements all the control functions necessary to build a power supply capable of optimally using available power-line current while minimizing linecurrent distortion. To do this, the UC1854 contains a voltage amplifier, an analog multiplier and divider, a current amplifier, and a fixed-frequency...