1

®

FN9056.10

ISL6527, ISL6527A

Single Synchronous Buck Pulse-Width

Modulation (PWM) Controller

The ISL6527, ISL6527A make simple work out of

implementing a complete control and protection scheme for

a DC/DC step-down converter. Designed to drive N-Channel

MOSFETs in a synchronous buck topology, the ISL6527,

ISL6527A integrate the control, output adjustment,

monitoring and protection functions into a single package.

The ISL6527, ISL6527A provide simple, single feedback loop,

voltage-mode control with fast transient response. The output

voltage can be regulated to as low as the provided external

reference. A fixed frequency oscillator reduces design

complexity, while balancing typical application cost and

efficiency.

The error amplifier features a 15MHz gain-bandwidth

product and 6V/µs slew rate, which enables high converter

bandwidth for fast transient performance. The resulting

PWM duty cycles range from 0% to 100%.

Protection from overcurrent conditions is provided by

operation appropriately. This approach simplifies the

implementation and improves efficiency by eliminating the

need for a current sense resistor.

Features

• Operates from 3.3V to 5V Input

• Utilizes an External Reference

• Drives N-Channel MOSFETs

• Simple Single-Loop Control Design

- Voltage-Mode PWM Control

• Fast Transient Response

- High Bandwidth Error Amplifier

- Full 0% to 100% Duty Cycle

• Lossless, Programmable Overcurrent Protection

• Converter Can Source and Sink Current

• Small Converter Size

- Internal Fixed Frequency Oscillator

-

ISL6527: 300kHz

-

ISL6527A: 600kHz

• Internal Soft-Start

• 14 Ld SOIC or 16 Ld 5x5 QFN

• QFN package:

- Compliant to JEDEC PUB95 MO-220 QFN - Quad Flat

No Leads - Package Outline

- Near Chip-Scale Package Footprint, which Improves

PCB Efficiency and has a Thinner Profile

• Pb-Free (RoHS compliant)

Applications

• Power Supplies for Microprocessors

-PCs

- Embedded Controllers

• Subsystem Power Supplies

- PCI/AGP/GTL+ Busses

- ACPI Power Control

- DDR SDRAM Bus Termination Supply

• Cable Modems, Set-Top Boxes, and DSL Modems

• DSP and Core Communications Processor Supplies

• Memory Supplies

• Personal Computer Peripherals

• Industrial Power Supplies

• 3.3V Input DC/DC Regulators

• Low Voltage Distributed Power Supplies

Data Sheet

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 1-888-468-3774

Copyright Intersil Americas Inc. 2003-2008. All Rights Reserved

All other trademarks mentioned are the property of their respective owners.

November 18, 2008