UC3886

UC1886 UC2886 UC3886 Average Current Mode PWM Controller IC FEATURES 10.3V - 20V Operating Range Low Offset Voltage Amplifier High Bandwidth Current and Voltage Amplifiers Low Offset Current Sense Undervoltage Lockout Trimmed 5 Volt Reference Externally Programmable Oscillator Charge Current 1.5A Peak Totem Pole Output Available in 16-pin DIL or SOIC Packages Amplifier DESCRIPTION The UC3886 family of PWM controller ICs is designed for DC-to-DC converters with average current mode control. It is designed for use in conjunction with the UC3910 4-bit DAC and Voltage Monitor. The UC3886 drives an external N-channel MOSFET and can be used to power the Intel Pentium® Pro and other high-end microprocessors. The UC3886 in conjunction with the UC3910 converts 5VDC to an adjustable output ranging from 2.0V to 3.5V in 100mV steps with 35mV DC system accuracy. The oscillator is programmed by the user’s selection of an external resistor and capacitor, and is designed for 300kHz typical operation. The voltage and current amplifiers have 3.5MHz gain-bandwidth product to satisfy high performance system requirements. The internal current sense amplifier permits the use of a low value current sense resistor, minimizing power loss. It has inputs and outputs accessible to allow user-selection of gain-setting resistors, and is internally compensated for a gain of 5 and above. The command voltage input is buffered and provided for use as the reference for the current sense amp...