uc3854dw

高功率因子前置穩壓器

產品信息

特性

• control boost pwm to 0.99 power factor
• limit line current distortion to <5%
• world-wide operation without switches
• feed-forward line regulation
• average current-mode control
• low noise sensitivity
• low start-up supply current
• fixed-frequency pwm drive
• low-offset analog multiplier/divider
• 1a totem-pole gate driver
• precision voltage reference

說明

the uc1854 provides active power factor correction for power systems that otherwise would draw non-sinusoidal 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 line-current distortion. to do this, the uc1854 contains a voltage amplifier, an analog multiplier/divider, a current amplifier, and a fixed-frequency pwm. in addition, the uc1854 contains a power mosfet compatible gate driver, 7.5v reference, line anticipator, load-enable comparator, low-supply detector, and over-current comparator.

the uc1854 uses average current-mode control to accomplish fixed-frequency current control with stability and low distortion.