1

LTC1096L/LTC1098L

Low Voltage, Micropower

Sampling 8-Bit Serial I/O

A/D Converters

December 1995

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.

However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-

tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

Final Electrical Specifications

DESCRIPTIO

S

FEATURE

s

Specified at 2.65V Minimum Supply

s

Maximum Supply Current: 80

µA

s

Auto Shutdown to 1nA

s

8-Pin SO Package

s

On-Chip Sample-and-Hold

s

Conversion Time: 32

µs

s

Sample Rates: 16.5ksps

s

I/O Compatible with SPI, MICROWIRE

The LTC

cessive approximation sampling A/D converters. They

typically draw only 40

µA of supply current when convert-

ing and automatically power down to a typical supply

current of 1nA between conversions. They are packaged in

8-pin SO packages and operate on a 3V supply. These 8-

bit, switched capacitor, successive approximation ADCs

include a sample-and-hold. The LTC1096L has a single

differential analog input. The LTC1098L offers a software

selectable 2-channel multiplexed input.

On-chip serial ports allow efficient data transfer to a wide

range of microprocessors and microcontrollers over three

wires. This, coupled with micropower consumption, makes

remote location possible and facilitates transmitting data

through isolation barriers.

The circuits can be used in ratiometric applications or with

an external reference. The high impedance analog inputs

and the ability to operate with reduced spans (to 1V full

scale) allow direct connection to sensors and transducers

in many applications, eliminating the need for gain stages.

s

Battery-Operated Systems

s

Remote Data Acquisition

s

Isolated Data Acquisition

s

Battery Monitoring

s

Temperature Measurement

S

APPLICATI

, LTC and LT are registered trademarks of Linear Technology Corporation.

MICROWIRE is a registered trademark of National Semiconductor Corporation.

APPLICATI

TYPICAL

SAMPLE FREQUENCY (kHz)

0.1

1

10

100

1000

1

10

100

1096/8 TA02

Supply Current vs Sample Rate

10

µW, SO-8 Package, 8-Bit A/D Converter

Samples at 200Hz and Runs Off a 3V Battery

3V

1

µF

ANALOG INPUT

CLK

8

7

6

5

1

2

3

4

LTC1096L

MPU

SERIAL DATA LINK

(MICROWIRE AND

SPI COMPATIBLE)

SERIAL DATA LINK

0V TO 3V RANGE

1096/8 TA01

CS/

SHDN

+IN

–IN

GND