ADS1225

¨

¨

ADS1226

1

FEATURES

DESCRIPTION

APPLICATIONS

MUX

SerialInterface

DS

ADC

VREFP VREFN

Buffer

AVDD

DVDD

GND

MUX

ADS1226Only

AINP1

AINN1

AINP2

AINN2

DRDY/DOUT

SCLK

TEMPEN

START

Oscillator

MODE

BUFEN

ADS1225

ADS1226

24-Bit Analog-to-Digital Converter

with One- and Two-Channel Differential Inputs and Internal Oscillator

2

• 100SPS Data Rate (High-Speed Mode)

The ADS1225 and ADS1226 are 24-bit delta-sigma

analog-to-digital

(A/D)

converters.

They

offer

• Single-Cycle Settling

excellent performance, ease-of-use, and low power in

• Easy Conversion Control with START Pin

a small 4mm × 4mm QFN package and are

• Automatic Shutdown

well-suited

for

demanding

high-resolution

• Low Noise: 4µV

measurements, especially in portable and other

space-saving and power-constrained applications.

Mode)

• Input Multiplexer with Two Differential

The ADS1225 and ADS1226 convert on command

Channels (ADS1226)

using a dedicated START pin. Simply pulse this pin to

initiate a conversion. Data is read in a single cycle for

• Voltage Reference Supports Ratiometric

retrieval over a 2-wire serial interface that easily

Measurements

connects

to

popular

microcontrollers

like

the

• Self-Calibrating

MSP430.

After

the

conversion

completes,

the

• Simple Read-Only 2-Wire Serial Interface

ADS1225 and ADS1226 automatically shuts down all

circuitry.

• Internal High-Impedance Input Buffer

Internal features include a two-channel multiplexer

• Internal Temperature Sensor

(ADS1226),

selectable

input

buffer,

temperature

• Internal Oscillator

sensor, and oscillator. The full-scale range is defined

• Low-Power: 1mW While Operating, < 1µA

by the external voltage reference with support

During Shutdown

provided for up to a 5V differential input signal. Two

operating modes allow for speed (100SPS data rate,

• Analog and Digital Supplies: 2.7V to 5.5V

15

µV

data rate).

• Hand-Held Instrumentation

The ADS1225/6 supports 2.7 to 5.5V analog and

digital supplies. Power consumption is 1mW while

• Portable Medical Equipment

converting with 3V supplies. The ADS1225 and

• Industrial Process Control

ADS1226 are fully specified over an extended

industrial temperature range of –40°C to +105°C.

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas

Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2

All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Copyright © 2006–2009, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.