1

®

FN9238.0

ISL8843

Industry Standard Single-Ended Current

Mode PWM Controller

The ISL8843 is an industry standard drop-in replacement for

the popular 28C43 and 18C43 PWM controllers suitable for

a wide range of power conversion applications including

boost, flyback, and isolated output configurations. Its fast

signal propagation and output switching characteristics

make this an ideal product for existing and new designs.

Features include 30V operation, low operating current, 90

µA

start-up current, adjustable operating frequency to 2MHz,

and high peak current drive capability with 20ns rise and fall

times.

Features

• 1A MOSFET gate driver

•90

µA start-up current, 125µA maximum

• 35ns propagation delay current sense to output

• Fast transient response with peak current mode control

• 30V operation

• Adjustable switching frequency to 2MHz

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

• Trimmed timing capacitor discharge current for accurate

deadtime/maximum duty cycle control

• 1.5MHz bandwidth error amplifier

• Tight tolerance voltage reference over line, load, and

temperature

• ±3% current limit threshold

• Pb-free plus anneal available and ELV, WEEE, RoHS

Compliant

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

ISL8843

(8 LD SOIC, MSOP)

TOP VIEW

PART NUMBER

RISING UVLO

MAX. DUTY CYCLE

ISL8843

8.4V

100%

Ordering Information

PART

NUMBER

PART

MARKING

TEMP.

RANGE (°C) PACKAGE

PKG.

DWG. #

ISL8843ABZ

(See Note)

8843 ABZ

-40 to 105

8 Ld SOIC

(Pb-free)

M8.15

ISL8843AUZ

(See Note)

8843Z

-40 to 105

8 Ld MSOP

(Pb-free)

M8.118

ISL8843MBZ

(See Note)

8843 MBZ

-55 to 125

8 Ld SOIC

(Pb-free)

M8.15

ISL8843MUZ

(See Note)

843MZ

-55 to 125

8 Ld MSOP

(Pb-free)

M8.118

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

NOTE: Intersil Pb-free plus anneal products employ special Pb-free

material sets; molding compounds/die attach materials and 100%

matte tin plate termination finish, which are RoHS compliant and

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-020.

COMP

FB

RTCT

VREF

VDD

OUT

GND

1

2

3

4

8

CS

7

6

5

Data Sheet

October 19, 2005

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. 2005 All Rights Reserved.

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