
1
FN9056.4
ISL6527
Single Synchronous Buck Pulse-Width
Modulation (PWM) Controller
The ISL6527 makes simple work out of implementing a
complete control and protection scheme for a DC-DC
stepdown converter. Designed to drive N-Channel
MOSFETs in a synchronous buck topology, the ISL6527
integrates the control, output adjustment, monitoring and
protection functions into a single package.
The ISL6527 provides 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/
μ
s 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
monitoring the r
DS(ON)
of the upper MOSFET to inhibit PWM
operation appropriately. This approach simplifies the
implementation and improves efficiency by eliminating the
need for a current sense resistor.
Ordering Information
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
- Uses upper MOSFET’s r
DS(ON)
Converter can source and sink current
Small converter size
- Internal fixed frequency oscillator
-
ISL6527: 300kHz
-
ISL6527A: 600kHz
- Internal soft-start
- 14 Lead SOIC or 16 Lead, 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
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
PART NUMBER
TEMP
RANGE (
o
C)
PACKAGE
PKG DWG. #
ISL6527CB
0 to 70
14 Lead SOIC
M14.15
ISL6527ACB
0 to 70
14 Lead SOIC
M14.15
ISL6527CR
0 to 70
16 Lead 5x5 QFN L16.5x5B
ISL6527ACR
0 to 70
16 Lead 5x5 QFN L16.5x5B
ISL6527IB
-40 to 85
14 Lead SOIC
M14.15
ISL6527AIB
-40 to 85
14 Lead SOIC
M14.15
ISL6527IR
-40 to 85
16 Lead 5x5 QFN L16.5x5B
ISL6527AIR
-40 to 85
16 Lead 5x5 QFN L16.5x5B
ISL6527EVAL1
ISL6527 SOIC Evaluation Board
ISL6527EVAL2
ISL6527 QFN Evaluation Board
ISL6527AEVAL2 ISL6527A SOIC Evaluation Board
ISL6527AEVAL2 ISL6527A QFN Evaluation Board
Data Sheet
July 2003
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2003. All Rights Reserved.
All other trademarks mentioned are the property of their respective owners.