FN8239 Rev 1.00

Page 1 of 7

January 21, 2005

FN8239

Rev 1.00

January 21, 2005

ISL88694

SMBus Accelerator (SMA)

DATASHEET

The ISL88694 SMBus accelerator (SMA) is a dual active

pull-up bus terminator designed to improve data

transmission speed on SMBus or similar 2-wire serial bus

bus.

The SMA detects rising input transitions with two internal

voltage references and two comparators per channel. After

the voltage on a data line crosses the first threshold

speed transition. After the voltage crosses the second

activated, leaving an active pull-up current of 275µA on the

line. When both channels are HIGH, the pull-up current for

both lines is reduced to 100µA to save power. Internal logic

ensures that the active and boost pull-up current sources are

not activated during downward transitions.

invariant for all power supply voltages between 2.7V and

5.5V.

A noise filter on each channel prevents the circuit from

responding to input transitions that do not exceed a voltage-

time threshold. To activate the boost circuit, the input must

The SMA permits operation of the bus at frequencies up to

100kHz, despite the capacitive loads of multiple devices

and/or long PC board traces. Enhanced ESD protection on

the accelerator pins are guaranteed to withstand 8kV ESD

(HBM) events.

The SMBus Accelerator provides an essential function in

SMBus applications because of distributed capacitance of

SMBus and multiple device input capacitances at various

can reliably increase their bus load without the risk of data

loss.

Features

• Active Termination for SMBus lines

• Enhances System Bus Signal Rise Time

• Increases Bus Capacity While Guaranteeing Data Integrity

• 2.2mA Rise Time Supply Current

• 8kV ESD Protection on SDA and SCL Pins

• Wide Operating Voltage Range: 2.7V to 5.5V

• Small Package - SOT23-5

• Pin-for-Pin Compatible with the LTC1694

• Pb-Free Available (RoHS Compliant)

Target Applications

•Servers

• Data Acquisition

•Routers

• Battery Chargers

• Portable Instrumentation

• Notebook

•PC

• Facilities Tracking System

Pinout

ISL88694

(5 LD SOT-23)

TOP VIEW

Ordering Information

PART NUMBER

PACKAGE

TEMP RANGE (°C)

ISL88694IH5

5-pin SOT

-40 to 85

ISL88694IH5Z (Note) 5-pin SOT (Pb-Free)

-40 to 85

Add “-TK” suffix for tape and reel.

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-020.

1

2

3

4

5

N.C.

SMBus1

GND

SMBus2