LTC1287

1

1287fa

FEATURES

DESCRIPTIO

KEY SPECIFICATIO S

TYPICAL APPLICATIO

3V Single Chip 12-Bit

Data Acquisition System

s

Single Supply 3.3V Operation

s

Built-In Sample-and-Hold

s

Direct 3-Wire Interface to Most MPU Serial Ports and

All MPU Parallel Ports

s

30kHz Maximum Throughput Rate

The LTC

contains a serial I/O successive approximation A/D con-

verter. The device specifications are guaranteed at a

supply voltage of 2.7V. It uses LTCMOS

pacitor technology to perform a 12-bit unipolar, A/D

conversion. The differential input has an on-chip sample-

and-hold on the (+) input.

The serial I/O is designed to communicate without external

hardware to most MPU serial ports and all MPU parallel

I/O ports allowing data to be transmitted and received over

three wires. The low voltage operating capability and the

low power consumption of this device make it ideally

suited for battery applications. Given the ease of use, small

package size and the minimum number of interconnects

for I/O, the LTC1287 can be used for remote sensing

applications.

s

Minimum Guaranteed Supply Voltage: 2.7V

s

Resolution: 12 Bits

s

Fast Conversion Time: 24

µs Max Over Temp.

s

Low Supply Current: 1.0mA

s

Battery-Powered Instruments

s

Data Logger

s

Data Acquisition Modules

LTCMOS is a trademark of Linear Technology Corporation

CLK

LTC1287

CS

+IN

–IN

GND

LT1004-1.2

10k

22

µF TANTALUM

22

µF

TANTALUM

+

–

DIFFERENTIAL INPUTS

COMMON MODE RANGE

FOR OVERVOLTAGE PROTECTION, LIMIT THE INPUT CURRENT TO 15mA

CONVERSION RESULTS ARE NOT VALID WHEN THE SELECTED CHANNEL OR

ON OVERVOLTAGE PROTECTION IN THE APPLICATIONS INFORMATION.

*

3V

LITHIUM

TO AND FROM MPU

1287 TA01

+

+

3V Differential Input Data Acquisition System

CODE

0

0.5

1.0

2048

LTC1287 TA02

0

–1.0

512

1024

1536

–0.5

2560

3072

3584

4096

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

APPLICATIO S