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SLUS311A – JULY 1999 – REVISED AUGUST 2000
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POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
D 5-Bit Digital-to-Analog Converter (DAC)
supports Intel Pentium II
D Microprocessor VID Codes
D Compatible with 5-V or 12-V Systems
D 1% Output Voltage Accuracy Ensured
D Drives 2 N-Channel MOSFETs
D Programmable Frequency to 800 kHz
D Power Good OV / UV / OVP Voltage Monitor
D Undervoltage Lockout and Softstart
Functions
D Short Circuit Protection
D Low Impedance MOSFET Drivers
D Chip Disable
AVAILABLE OPTIONS
T
J
PACKAGED DEVICES
T
J
D, 16-PIN J, 16-PIN N, 16-PIN PW, 16-PIN
0°C TO 70°C UCC3588D UCC3588J UCC3588N UCC3588PW
description
The UCC3588 synchronous step-down (Buck) regulator provides accurate high efficiency power conversion.
Using few external components, the UCC1588 converts 5V to an adjustable output ranging from 3.5 VDC to
2.1 VDC in 100-mV steps and 2.05 VDC to 1.3 VDC in 50-mV steps with 1% dc system accuracy. A high level
of integration and novel design allow this 16-pin controller to provide a complete control solution for today’s
demanding microcontroller power requirements. Typical applications include on board or VRM based power
conversion for Intel Pentium II microprocessors, as well as other processors from a variety of manufacturers.
High efficiency is obtained through the use of synchronous rectification.
The softstart function provides a controlled ramp up of the system output voltage. Overcurrent circuitry detects
a hard (or soft) short on the system output voltage and invokes a timed softstart/shutdown cycle to reduce the
PWM controller on time to 5%.
The oscillator frequency is externally programmed with RT and operates over a range of 50 kHz to 800 kHz.
The gate drivers are low impedance totem pole output stages capable of driving large external MOSFETs. Cross
conduction is eliminated by fixed delay times between turn off and turn on of the external high side and
synchronous MOSFETs. The chip includes undervoltage lockout circuitry which assures the correct logic states
at the outputs during power up and power down.
This device is available in 16-pin surface mount, plastic and ceramic DIP, and TSSOP packages. The UCC3588
is specified for operation from 0°C to 70°C.
Copyright 2000, Texas Instruments Incorporated
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
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VSENSE
ISNS
SS/ENBL
D0
D1
D2
D3
D4
RT
VCC
DRVLO
DRVHI
GND
PWRGOOD
VFB
COMP
D, J, N AND PW PACKAGES
(TOP VIEW)
