ADS7945 Datasheet, PDF (1/49 Pages) Texas Instruments – 14-Bit, 2 MSPS, Dual-Channel, Differential/Single-Ended, Ultralow-Power Analog-to-Digital Converters

ADS7945
ADS7946
www.ti.com
SBAS539B – JUNE 2011 – REVISED SEPTEMBER 2011
14-Bit, 2 MSPS, Dual-Channel, Differential/Single-Ended,
Ultralow-Power Analog-to-Digital Converters
Check for Samples: ADS7945, ADS7946
FEATURES
1
•23 Sample Rate: 2 MSPS
• 14-Bit, Pin-Compatible with 8/10/12-bit
ADS7947/8/9 Family (ADS7946)
• Outstanding Performance:
– SNR: 84 dB (ADS7945)
– No Missing Codes
– INL: 1.5 LSB (max) (ADS7945)
• Low Power:
– 11.6 mW at 2 MSPS Operation
– Auto Power-Down at Lower Speeds:
– 7.2 mW at 500 kSPS
– 1.4 mW at 100 kSPS
– 0.3 mW at 20 kSPS
• Wide Supply Range:
– Analog: 2.7 V to 5.25 V
– Digital: 1.65 V to AVDD
• Simple Serial Interface (SPI)
• Fully Specified from –40°C to +125°C
• Tiny Footprint: 3 mm × 3 mm QFN
APPLICATIONS
• Optical Networking
• Medical Instrumentation
• Battery-Powered Equipment
• Data Acquisition Systems
DESCRIPTION
The ADS7945/6 are 14-bit, 2 MSPS analog-to-digital
converters (ADCs), with differential and single-ended
inputs, respectively. The devices operate at a 2
MSPS sample rate with a standard 16-clock data
frame. The devices feature both outstanding dc
precision and excellent dynamic performance; the
ADS7946 is pin-compatible with the 8/10/12-bit
ADS7947/8/9 devices. The devices include a
two-channel input multiplexer and a low-power
successive approximation register (SAR) ADC with
an inherent sample-and-hold (S/H) input stage.
The ADS7945/6 support a wide analog supply range
that allows the full-scale input range to extend to ±5 V
differential or 5 V single-ended. A simple SPI™, with
a digital supply that can operate as low as 1.65 V,
allows for easy interfacing to a wide variety of digital
controllers. Automatic power-down can be enabled
when operating at slower speeds to dramatically
reduce power consumption.
Offered in a tiny 3 mm × 3 mm QFN package, the
ADS7945/6 are fully specified over the extended
temperature range of –40°C to +125°C and are
suitable for a wide variety of data acquisition
applications where high performance, low power, and
small package size are key.
AVDD
REF REFGND DVDD
AVDD
REF REFGND DVDD
AIN0P
AIN0N
MUX
S/H
AIN1N
AIN1P
SAR
ADC
ADS7945
SPI
PDEN
CS
SCLK
SDO
CH SEL
AIN0
AIN0GND
AIN1GND
AIN1
MUX
S/H
SAR
ADC
ADS7946 _PDEN
CS
SPI
SCLK
SDO
CH SEL
GND
GND
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