1

®

High Voltage Synchronous Rectified Buck

MOSFET Driver

The ISL6208A is a high frequency, dual MOSFET driver,

optimized to drive two N-Channel power MOSFETs in a

synchronous-rectified buck converter topology. It is

especially suited for mobile computing applications that

require high efficiency and excellent thermal performance.

This driver, combined with an Intersil multiphase Buck PWM

controller, forms a complete single-stage core-voltage

regulator solution for advanced mobile microprocessors.

The ISL6208A features 4A typical sinking current for the

lower gate driver. This current is capable of holding the lower

MOSFET gate off during the rising edge of the Phase node.

This prevents shoot-through power loss caused by the high

dv/dt of phase voltages. The operating voltage matches the

30V breakdown voltage of the MOSFETs commonly used in

mobile computer power supplies.

The ISL6208A also features a three-state PWM input that,

working together with Intersil’s multiphase PWM controllers,

will prevent negative voltage output during CPU shutdown.

This feature eliminates a protective Schottky diode usually

seen in a microprocessor power systems.

MOSFET gates can be efficiently switched up to 2MHz using

the ISL6208A. Each driver is capable of driving a 3000pF

load with propagation delays of 15ns and transition times

under 10ns. Bootstrapping is implemented with an internal

Schottky diode. This reduces system cost and complexity,

while allowing the use of higher performance MOSFETs.

Adaptive shoot-through protection is integrated to prevent

both MOSFETs from conducting simultaneously.

A diode emulation feature is integrated in the ISL6208A to

enhance converter efficiency at light load conditions. This

feature also allows for monotonic start-up into pre-biased

outputs. When diode emulation is enabled, the driver will

allow discontinuous conduction mode by detecting when the

inductor current reaches zero and subsequently turning off

the low side MOSFET gate. Programmable dead-time

control with gate threshold monitoring is also integrated to

prevent both MOSFETs from conducting simultaneously.

Related Literature

• Technical Brief TB363 “Guidelines for Handling and

Processing Moisture Sensitive Surface Mount Devices

(SMDs)”

• Technical Brief TB389 “PCB Land Pattern Design and

Surface Mount Guidelines for MLFP Packages”

• Technical Brief TB447 “Guidelines for Preventing Boot-to-

Phase Stress on Half-Bridge MOSFET Driver ICs”

Features

• Dual MOSFET Drives for Synchronous Rectified Bridge

• Adaptive Shoot-Through Protection

- Active Gate Threshold Monitoring

- Programmable Dead-Time

•0.5

Ω On-Resistance and 4A Sink Current Capability

• Supports High Switching Frequency up to 2MHz

- Fast Output Rise and Fall Time

- Low Propagation Delay

• Three-State PWM Input for Power Stage Shutdown

• Internal Bootstrap Schottky Diode

• Low Bias Supply Current (5V, 100µA)

• Diode Emulation for Efficiency and Pre-Biased Startup

• VCC POR (Power-On-Reset) Feature Integrated

• Pin-to-pin Compatible with ISL6207, ISL6208, ISL6209

• 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 Plus Anneal Available (RoHS Compliant)

Applications

• Supplies for Intel® and AMD® Mobile Microprocessors

• High Frequency, Low Profile DC/DC Converters

• High Current Low Output Voltage DC/DC Converters

• High Input Voltage DC/DC Converters

Ordering Information

PART NUMBER

PART

MARKING

TEMP.

RANGE

(°C)

PACKAGE

PKG.

DWG.

#

ISL6208ACBZ

(Note)

ISL6208ACBZ -10 to 100 8 Ld SOIC

(Pb-Free)

M8.15

ISL6208ACBZ-T

(Note)

ISL6208ACBZ 8 Ld SOIC Tape and Reel

(Pb-Free)

ISL6208ACRZ

(Note)

08AZ

-10 to 100 8 Ld 3x3 QFN

(Pb-Free)

L8.3x3

ISL6208ACRZ-T

(Note)

08AZ

8 Ld 3x3 QFN Tape and Reel

(Pb-Free)

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.

Data Sheet

February 15, 2006

FN9272.0

ISL6208A

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. 2006. All Rights Reserved

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