ADS8634 Datasheet, PDF (1/75 Pages) Texas Instruments – 12-Bit, 1MSPS, 4-/8-Channel, Bipolar-Input, SAR Analog-to-Digital Converter

ADS8634
ADS8638
www.ti.com
SBAS541A – MAY 2011 – REVISED AUGUST 2011
12-Bit, 1MSPS, 4-/8-Channel, Bipolar-Input, SAR Analog-to-Digital Converter
with Software-Selectable Ranges
Check for Samples: ADS8634, ADS8638
FEATURES
1
•23 Selectable Input Range:
±10V, ±5V, ±2.5V, 0V to 10V, or
0V to 5V
Up to ±12V with External Reference
• No Latent Conversions Up to 1MSPS
• Outstanding Performance:
12 Bits No Missing Codes
INL: ±0.9LSB
SNR: 71.8dB
• Highly Integrated:
4- or 8-Channel Input Mux
Temperature Sensor
Internal Voltage Reference
Alarm Thresholds for Each Channel
• Low Power:
14.45mW at 1MSPS
5.85mW at 0.1MSPS
Flexible Power-Down Mode
• SPI™-Compatible Serial Interface
• Extended Temperature Range:
–40°C to +125°C
• Small Footprint: 4mm × 4mm QFN Package
DESCRIPTION
The ADS8634 and ADS8638 (ADS8634/8) are 12-bit
analog-to-digital converters (ADCs) capable of
measuring inputs up to ±10V at 1MSPS. Using a
successive approximation register (SAR) core, these
ADCs provide a sample-and-hold front-end with no
latency in conversions. The ADS8634 includes an
input multiplexer (mux) for measuring up to four
inputs. The ADS8638 can measure up to eight inputs.
In addition to the input multiplexer, the ADS8634/8
feature an internal temperature sensor, voltage
reference, and a digital comparator for setting alarm
thresholds on each input; therefore, a minimal
amount of external components are required. A
simple SPI-compatible interface provides for
communication and control. The digital supply
operates from 5V all the way down to 1.8V for direct
connection to a wide range of processors and
controllers.
Ideal for demanding industrial measurement
applications, the ADS8634/8 are fully specified over
the extended industrial temperature range of –40°C
to +125°C and are available in a small form-factor
QFN-24 package.
APPLICATIONS
• Industrial Process Controls (PLC)
• Data Acquisition Systems
• High-Speed, Closed-Loop Systems
• Digital Power Supplies
HVDD
AIN0
AIN1
AIN2
AIN3
MUX
AINGND
Temp
Sensor
HVSS
AVDD
REF
REF
DVDD
Alarm
Threshold
Comparator
ADC
SPI
ADS8634
AGND
REFGND
DGND
HVDD
AL_PD
CS, SCLK,
DIN, DOUT
AIN0
AIN1
AIN2
AIN3
AIN4
AIN5
AIN6
AIN7
AINGND
Temp
Sensor
MUX
HVSS
AVDD
REF
REF
DVDD
Alarm
Threshold
Comparator
ADC
SPI
ADS8638
AGND
REFGND
DGND
AL_PD
CS, SCLK,
DIN, DOUT
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.
SPI is a trademark of Motorola.
2
All other trademarks are the property of their respective owners.
3
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2011, Texas Instruments Incorporated