FN9010 Rev 3.00

Page 1 of 18

Dec 1, 2004

FN9010

Rev 3.00

Dec 1, 2004

ISL6402A

1.4MHz Dual, 180° Out-of-Phase, Step-Down PWM and Single Linear Controller

DATASHEET

The ISL6402A is a high-performance, triple-output controller

optimized for converting wall adapter, battery or network

intermediate bus DC input supplies into the system supply

voltages required for a wide variety of applications. Each

output is adjustable down to 0.8V. The two PWMs are

synchronized 180o out of phase reducing the RMS input

current and ripple voltage.

The ISL6402A incorporates several protection features. An

adjustable overcurrent protection circuit monitors the output

current by sensing the voltage drop across the lower

MOSFET. Hiccup mode overcurrent operation protects the

DC-DC components from damage during output

overload/short circuit conditions. Each PWM has an

independent logic-level shutdown input (SD1 and SD2).

A single PGOOD signal is issued when soft-start is complete

on both PWM controllers and their outputs are within 10% of

the set point and the linear regulator output is greater than

75% of its setpoint. Thermal shutdown circuitry turns off the

device if the junction temperature exceeds +150°C.

Features

• Wide Input Supply Voltage Range . . . . . . . . . 4.5V to 24V

• Three Independently Programmable Output Voltages

• Switching Frequency . . . . . . . . . . . . . . . . . . . . . . .1.4MHz

• Out of Phase PWM Controller Operation

- Reduces Required Input Capacitance and Power

Supply Induced Loads

• No External Current Sense Resistor

- Uses Lower MOSFET’s rDS(ON)

• Bi-directional Frequency Synchronization for

Synchronizing Multiple ISL6402As

• Programmable Soft-Start

• Extensive circuit protection functions

- PGOOD

-UVLO

- Overcurrent

- Overtemperature

- Independent Shutdown for Both PWMs

• Excellent Dynamic Response

- Voltage Feed-Forward with Current Mode Control

• QFN Packages:

- QFN - 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 Available (RoHS Compliant)

Applications

• Power Supplies with Multiple Outputs

• xDSL Modems/Routers

• DSP, ASIC, and FPGA Power Supplies

• Set-Top Boxes

• Dual Output Supplies for DSP, Memory, Logic,

P Core

and I/O

• Telecom Systems

Ordering Information

PART NUMBER

TEMP. RANGE

(°C)

PACKAGE

PKG.

DWG. #

ISL6402AIR

-40 to 85

28 Ld QFN

L28.5x5

ISL6402AIR-T

28 Ld QFN Tape and Reel

L28.5x5

ISL6402AIR-TK

28 Ld QFN Tape and Reel

L28.5x5

ISL6402AIRZ

(See Note)

-40 to 85

28 Ld QFN

(Pb-free)

L28.5x5

ISL6402AIRZ-T

(See Note)

28 Ld QFN Tape and Reel

(Pb-free)

L28.5x5

NOTE: Intersil Pb-free 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-020C.

NOT RECOMMENDED FOR NEW DESIGNS

REFER TO ISL6441