1

®

FN4138.8

HI7191

24-Bit, High Precision, Sigma Delta A/D

Converter

The Intersil HI7191 is a monolithic instrumentation, sigma

delta A/D converter which operates from

±5V supplies. Both

the signal and reference inputs are fully differential for

maximum flexibility and performance. An internal

Programmable Gain Instrumentation Amplifier (PGIA)

provides input gains from 1 to 128 eliminating the need for

external pre-amplifiers. The on-demand converter

auto-calibrate function is capable of removing offset and gain

errors existing in external and internal circuitry. The on-board

user programmable digital filter provides over 120dB of

60/50Hz noise rejection and allows fine tuning of resolution

and conversion speed over a wide dynamic range. The

HI7190 and HI7191 are functionally the same device, but the

HI7190 has tighter linearity specs.

The HI7191 contains a serial I/O port and is compatible with

most synchronous transfer formats including both the

Motorola 6805/11 series SPI and Intel 8051 series SSR

protocols. A sophisticated set of commands gives the user

control over calibration, PGIA gain, device selection, standby

mode, and several other features. The On-chip Calibration

Registers allow the user to read and write calibration data.

Features

• 20-Bit Resolution with No Missing Code

• 0.0015% Integral Non-Linearity (Typ)

•20mV to

±2.5V Full Scale Input Ranges

• Internal PGIA with Gains of 1 to 128

• Serial Data I/O Interface, SPI Compatible

• Differential Analog and Reference Inputs

• Internal or System Calibration

• 120dB Rejection of 60/50Hz Line Noise

• Settling Time of 4 Conversions (Max) for a Step Input

• Pb-Free Plus Anneal Available (RoHS Compliant)

Applications

• Process Control and Measurement

• Industrial Weight Scales

• Part Counting Scales

• Laboratory Instrumentation

• Seismic Monitoring

• Magnetic Field Monitoring

Related Literature

• Technical Brief TB363 “Guidelines for Handling and

Processing Moisture Sensitive Surface Mount Devices

(SMDs)”

• TB348 “HI7190/1 Negative Full Scale Error vs

Conversion Frequency”

• AN9504 “A Brief Intro to Sigma Delta Conversion”

• TB329 “Intersil Sigma Delta Calibration Technique”

• AN9505 “Using the HI7190 Evaluation Kit”

• TB331 “Using the HI7190 Serial Interface”

• AN9527 “Interfacing HI7190 to a Microcontroller”

• AN9532 “Using HI7190 in a Multiplexed System”

• AN9601 “Using HI7190 with a Single +5V Supply”

Ordering Information

PART

NUMBER

PART

MARKING

TEMP.

RANGE

(°C)

PACKAGE

PKG.

DWG. #

HI7191IP

HI7191IP

-40 to 85 20 Ld PDIP

E20.3

HI7191IPZ

(See Note)

HI7191IPZ

-40 to 85 20 Ld PDIP*

(Pb-free)

E20.3

HI7191IB

HI7191IB

-40 to 85 20 Ld SOIC

M20.3

HI7191IBZ

(See Note)

HI7191IBZ

-40 to 85 20 Ld SOIC

(Pb-free)

M20.3

HI7191IBZ-T

(See Note)

HI7191IBZ

-40 to 85 20 Ld SOIC

Tape and Reel

(Pb-free)

M20.3

HI7190EVAL

Evaluation Kit

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.

*Pb-free PDIPs can be used for through hole wave solder processing

only. They are not intended for use in Reflow solder processing

applications.

Data Sheet

June 1, 2006

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. 2003, 2005, 2006. All Rights Reserved

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