UNITRODE UC2852
the UC2852 is specified for operation from -40°C to +85°C, and the UC3852 is specified for operation from 0°C to +70°C.| Part No. | UC2852 |
|---|---|
| Datasheet | UC2852 Download |
| Manufacturer |  UNITRODE |
| Description | High Power-Factor Preregulator |
| Buy | Stock & Price |
FEATURES
● Low-Cost Power Factor Correction● Power Factor Greater Than 0.99
● Few External Parts Required
● Controlled On-Time Boost PWM
● Zero-Current Switching
● Limited Peak Current
● Min and Max Frequency Limits
● Starting Current Less Than 1mA
● High-Current FET Drive Output
● Under-Voltage Lockout
DESCRIPTION
The UC1852 provides a low-cost solution to active power-factor correction (PFC) for systems that would otherwise draw high peak current pulses from AC power lines. This circuit implements zero-current switched boost conversion, producing sinusoidal input currents with a minimum of external components, while keeping peak current substantially below that of fully-discontinuous converters. The UC1852 provides controlled switch on-time to regulate the output bulk DC voltage, an off-time defined by the boost inductor, and a zero-current sensing circuit to reactivate the switch cycle. Even though switching frequency varies with both load and instantaneous line voltage, it can be maintained within a reasonable range to minimize noise generation.
