CONTROLLED FREQUENCY POWER FACTOR CORRECTION CIRCUIT AND METHOD

摘要

A power factor correction (PFC) circuit (10) includes a latch (16) having an output that initiates a coil current (I>COIL<) in response to a transition edge of a clock signal (CLOCK) to generate a PFC signal (V>OUT<). An input receives a control signal (TERM). A current modulation circuit (14) has a first input (36) coupled for receiving the PFC signal to establish a charging time (T>CH<) of the coil current. A second input senses the coil current to establish a duty cycle of the coil current over a period of the clock signal, and an output (38) provides the control signal as a function of the charging time and the duty cycle.