ADS1271
SBAS306A − NOVEMBER 2004 − REVISED DECEMBER 2004
24 Bit, Wide Bandwidth
Analog to Digital Converter
FEATURES
D
105kSPS Data Rate
D
AC Performance:
51kHz Bandwidth
109dB SNR (High-Resolution Mode)
−105dB THD
DESCRIPTION
The ADS1271 is a 24-bit, delta-sigma analog-to-digital
converter (ADC) with a data rate up to 105kSPS. It offers
a unique combination of excellent DC accuracy and
outstanding
AC
performance.
The
high-order,
chopper-stabilized modulator achieves very low drift with
low in-band noise. The onboard decimation filter
suppresses modulator and signal out-of-band noise. The
ADS1271 provides a usable signal bandwidth up to 90%
of the Nyquist rate with less than 0.005dB of ripple.
Traditionally, industrial delta-sigma ADCs offering good
drift performance use digital filters with large passband
droop. As a result, they have limited signal bandwidth and
are mostly suited for DC measurements. High-resolution
ADCs in audio applications offer larger usable bandwidths,
but the offset and drift specification are significantly
weaker than their industrial counterparts. The ADS1271
combines these converters, allowing high-precision
industrial measurement with excellent DC and AC
specifications ensured over an extended industrial
temperature range.
Three operating modes allow for optimization of speed,
resolution, and power. A selectable SPI or a frame-sync
serial interface provides for convenient interfacing to
microcontrollers or DSPs. All operations, including internal
offset calibration, are controlled directly by pins; there are
no registers to program.
VREFP VREFN
AVDD
Control
Logic
DVDD
SYNC/PDWN
MODE
CLK
AINP
DRDY/FSYNC
SCLK
DOUT
DIN
FORMAT
D
DC Accuracy:
D
1.8µV/°C Offset Drift
2ppm/°C Gain Drift
Selectable Operating Modes:
High-Speed: 105kSPS Data Rate
High-Resolution: 109dB SNR
Low-Power: 35mW Dissipation
Power-Down Control
Digital Filter:
Linear Phase Response
Passband Ripple:
±0.005dB
Stop Band Attenuation: 100dB
D
D
D
Internal Offset Calibration On Command
D
Selectable SPIt or Frame Sync Serial Interface
D
Designed for Multichannel Systems:
D
D
D
D
Daisy-Chainable Serial Interface
Easy Synchronization
Simple Pin-Driven Control
Specified from −40°C to +105°C
Analog Supply: 5V
Digital Supply: 1.8V to 3.3V
APPLICATIONS
D
Vibration/Modal Analysis
D
Acoustics
D
Dynamic Strain Gauges
D
Pressure Sensors
D
Test and Measurement
∆Σ
Modulator
Digital
Filter
Serial
Interface
AINN
AGND
DGND
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.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Products
conform to specifications per the terms of Texas Instruments standard warranty.
Production processing does not necessarily include testing of all parameters.
Copyright
2004, Texas Instruments Incorporated
www.ti.com
BURR-BROWN [ BURR-BROWN CORPORATION ]
