LINEAR TECHNOLOGY - 1 LTC1091 LTC1092 LTC1093 LTC1094 Data Sheet

LTC1091/LTC1092 LTC1093/LTC1094

1-, 2-, 6- and 8-Channel, 10-Bit Serial I/O Data Acquisition Systems

FEATURES and-holds. On-chip serial ports allow efficient data trans- fer to a wide range of microprocessors and microcontrol-

Programmable Features

lers. These circuits can provide a complete data acquisi-

Unipolar/Bipolar Conversions

tion system in ratiometric applications or can be used with

Differential/Single-Ended Multiplexer

an external reference in others.

Configurations

The high impedance analog inputs and the ability to

Sample-and-Holds

operate with reduced spans (below 1V full scale) allow

Single Supply 5V, 10V or ±5V Operation

direct connection to sensors and transducers in many

Direct 3- or 4-Wire Interface to Most MPU Serial

applications, eliminating the need for gain stages.

Ports and All MPU Parallel I/O Ports Analog Inputs Common Mode to Supply Rails An efficient serial port communicates without external Resolution: 10 Bits hardware to most MPU serial ports and all MPU parallel Total Unadjusted Error (A Grade): ±1LSB Over Temp I/O ports allowing eight channels of data to be transmitted Fast Conversion Time: 20µs over as few as three wires. This, coupled with low power Low Supply Current consumption, makes remote location possible and facili- LTC1091: 3.5m A Max, 1.5m A Typ tates transmitting data through isolation barriers. LTC1092/LTC1093/LTC1094: 2.5m A Max, 1m A Typ

Temperature drift of offset, linearity and full-scale error

LI NE AR IT ER RO (L SB • V RE F)

are all extremely low (1ppm/°C typically) allowing all DESCRIPTIO grades to be specified with offset and linearity errors of ±0.5LSB maximum over temperature. In addition, the A

The LTC®1091/LTC1092/LTC1093/LTC1094 10-bit data

grade devices are specified with full-scale error and total

acquisition systems are designed to provide complete

unadjusted error (including the effects of offset, linearity

function, excellent accuracy and ease of use when digitiz-

and full-scale errors) of ±1LSB maximum over tempera-

ing analog data from a wide variety of signal sources and

ture. The lower grade has a full-scale specification of

transducers. Built around a 10-bit, switched capacitor,

±2LSB for applications where full scale is adjustable or

successive approximation A/D core, these devices include

less critical.

software configurable analog multiplexers and bipolar and

unipolar conversion modes as well as on-chip sample- , LTC and LT are registered trademarks of Linear Technology Corporation.

TYPICAL APPLICATION

1.25 VCC = 5V

MPU 0.75

CS P1.4

(VREF) 0.50

ANALOG INPUT #1

CH0 CLK P1.3

0V TO 5V RANGE

LTC1091

ANALOG INPUT #2

CH1 DOUT P1.2 0.25

0V TO 5V RANGE

SERIAL DATA LINK 1091 TA01

GND DIN

FOR 8051 CODE SEE APPLICATIONS INFORMATION SECTION

REFERENCE VOLTAGE (V)

1091 TA02