1

®

FN9152.1

ISL6729

Low-Cost Single-Ended Current-Mode

PWM for Microcontroller Based Power

Converters

The ISL6729 pulse width modulating (PWM) current mode

controller is designed for power conversion applications that

are based on a microcontroller or other device which can

generate a digital clock signal at the desired switching

frequency. Similar to the ISL684x family of products, the

ISL6729 provides the basic current mode PWM control

features, but eliminates the error amplifier, the oscillator, and

the reference. An external clock signal applied to the

oscillator input provides the time base and sets the

maximum duty cycle. The reduced feature set is ideal for

those applications where a microcontroller is available to

provide the monitor and control functions. The analog PWM

provides the cycle by cycle peak current mode control,

leaving the monitor and control overhead to the

microcontroller.

Features

• 5V Operation

• 1A MOSFET gate driver

•400

µA startup current

• 30ns propagation delay current sense to output

• Fast transient response with peak current mode control

• Switching frequency to 2MHz

• 20ns rise and fall times with 1nF output load

• Maximum Duty Cycle Determined by Clock Input Duty

Cycle

• Tight tolerance current limit threshold

• Pb-free available

Applications

• Telecom and Datacom Power

• Wireless Base Station Power

• File Server Power

• Industrial Power Systems

• PC Power Supplies

• Isolated Buck and Flyback Regulators

• Boost Regulators

Pinout

ISL6729 (8-PIN SOIC, MSOP)

TOP VIEW

Ordering Information

PART NUMBER

TEMP. RANGE

(°C)

PACKAGE

PKG.

DWG. #

ISL6729IB

-40 to 105

8 Ld SOIC

M8.15

ISL6729IBZ

(See Note)

-40 to 105

8 Ld SOIC

(Pb-free)

M8.15

ISL6729IU

-40 to 105

8 Ld MSOP

M8.118

ISL6729IUZ

(See Note)

-40 to 105

8 Ld MSOP

(Pb-free)

M8.118

Add -T to part number for Tape and Reel packaging.

NOTE: Intersil Pb-free products employ special Pb-free material

sets; molding compounds/die attach materials and 100% matte tin

plate termination finish, which is compatible with both SnPb and

Pb-free soldering operations. Intersil Pb-free products are MSL

classified at Pb-free peak reflow temperatures that meet or exceed

the Pb-free requirements of IPC/JEDEC J Std-020B.

PART NUMBER

RISING UVLO

MAX. DUTY CYCLE

ISL6729

4.75V

100%

COMP

N/C

CS

CLKS

1

2

3

4

8

7

6

5

N/C

VDD

OUT

GND

Data Sheet

July 2004

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

1-888-INTERSIL or 321-724-7143

Copyright © Intersil Americas Inc. 2004 All Rights Reserved.

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