Description
●The FAN4800 is a controller for power-factor-corrected, switched-mode power supplies. Power Factor Correction (PFC) allows the use of smaller, lower-cost bulk capacitors, reduces power line loading and stress on the switching FETs, and results in a power supply that fully complies with IEC-1000-3-2 specifications. Intended as a BiCMOS version of the industry-standard ML4800, the
●FAN4800 includes circuits for the implementation of leading edge, average current, boost-type power factor correction, and a trailing-edge Pulse Width Modulator (PWM). A gate driver with 1A capabilities minimizes the need for external driver circuits. Low-power require ments improve efficiency and reduce component costs.
●Features
●Low start-up current (100µA typical)
●Low operating current (2.5mA typical)
●Low total harmonic distortion, high power factor
●Pin-compatible upgrade for the ML4800
●Average current, continuousor discontinuous boost, leading-edge PFC
●Slew rate enhanced transconductance error amplifier for ultra-fast PFC response
●Internally synchronized leading edge PFC and trailing edge PWM
●Reduction of ripple current in the storage capacitor between the PFC and PWM sections
●PWM configurable for current-mode or voltage-mode operation
●Additional folded-back current limit for PWM section
●20V BiCMOS process
●VINOK guaranteed turn-on PWM at 2.25V
●VCCOVP comparator, low-power detect comparator
●Current-fed gain modulator for improved noise immunity
●Brownout control, over-voltage protection, UVLO, soft-start, and reference OK
●Available in 16-DIP, 16-SOIC (wide) packages
●Applications
●Desktop PC Power Supply
●Internet Server Power Supply
●Uninterruptible Power Supply (UPS)
●Battery Charger
●DC Motor Power Supply
●Monitor Power Supply
●Telecom System Power Supply
●Distributed Power
