AD7797: Low Power 24-Bit Sigma-Delta A/D Converter for Bridge Sensors
The AD7797 is a complete analog front end for high precision bridge sensor applications such as weighscales. The AD7797 contains a ∑-∆ ADC capable of 24-bit resolution. The on-chip instrumentation ...More
AD7797: Low Power 24-Bit Sigma-Delta A/D Converter for Bridge Sensors
Product Description
The AD7797 is a complete analog front end for high precision bridge sensor applications such as weighscales. The AD7797 contains a ∑-∆ ADC capable of 24-bit resolution. The on-chip instrumentation amplifier has a fixed gain of 128 so signals of small amplitude such as those from bridge sensors can be interfaced directly to the ADC.
The part has one differential input. The device also contains a temperature sensor which is internally connected to the ADC. This temperature sensor can be used to perform temperature compensation of the bridge.
The device can be operated with the internal clock, or alternatively, an external clock can be used. The output data rate from the parts is software-programmable and can be varied from 4.17 Hz to 123 Hz.
The part operates with a power supply from 2.7 V to 5.25 V. It consumes a current of 250 µA typical and is housed in a 16-lead TSSOP package.
Applications
Features
- RMS Noise: 65 nV
- Instrumentation amp
- Temperature Sensor
- Internal clock oscillator
- Simultaneous 50 Hz/60 Hz rejection
- Update rate: 4.17 Hz to 123 Hz
- Current: 250 µA typ
- Power-down: 1 µA
- Power supply: 2.7 V to 5.25 V
- –40°C to +85°C temperature range
- Independent interface power supply
- 16-lead TSSOP package
Diagrams
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- Other Diagrams
- Symbols and Footprints
Functional Block Diagram for AD7797
Low Power 24-Bit Sigma-Delta A/D Converter for Bridge Sensors
Other Diagrams for AD7797
Low Power 24-Bit Sigma-Delta A/D Converter for Bridge Sensors
Pin Configuration
Circuit Diagram
Functional Block Diagram for AD7797
AD7262 - 1 MSPS, 12-Bit, Simultaneous Sampling SAR ADC with PGA and Four Comparators
AD7657-1 - 250 kSPS, 6-Channel, Simultaneous Sampling, Bipolar 14-Bit ADC
AD7658-1 - 250 kSPS, 6-Channel, Simultaneous Sampling, Bipolar 12-Bit ADC
AD7264 - True Differential, Dual, 1 MSPS, 14-Bit/12-Bit, 2-Channel SAR ADC With PGA
| Part# | Res | Throughput Rate | # of Inputs | Operating Pwr Diss |
|---|---|---|---|---|
| AD7797 | 24 | 123SPS | 1 | 1.6mW |
| AD7796 | 16 | 123SPS | 1 | 1.6mW |
| AD7766 | 24 | 128KSPS | 1 | 18mW |
| AD7767 | 24 | 128KSPS | 1 | 18mW |
| AD9874 | 24 | 541.5KSPS | 1 | 79.5mW |
| AD7791 | 24 | 120SPS | 1 | 800µW |
| AD7764 | 24 | 312KSPS | 1 | 371mW |
| AD7765 | 24 | 156KSPS | 1 | 371mW |
| AD7763 | 24 | 625KSPS | 1 | 956mW |
| AD7760 | 24 | 2.5MSPS | 1 | 958mW |
| AD7762 | 24 | 625KSPS | 1 | 958mW |
AD7797 Model Options
| Model | Status | Package | Pins | Temp. Range |
Price* (1000 pcs.) |
Production** Availability |
ROHS Compilant | Samples Cart | Purchase Cart |
|---|---|---|---|---|---|---|---|---|---|
| AD7797BRUZ | Prodn | 16 ld TSSOP | 16 | Ind | $3.39 | 08/29/2008 |
Y
Material Declaration |
Add To Cart | Add To Cart |
| AD7797BRUZ-REEL | Prodn | 16 ld TSSOP | 16 | Ind | $3.39 | - |
Y
Material Declaration |
Contact ADI | Add To Cart |
| EVAL-AD7797EBZ | Prodn | EVALUATION BOARDS | - | TBD | $130.55 | 10/24/2008 | Y | Contact ADI | Add To Cart |
Help
- Pre-Release: The model has not been released to general production, but samples may be available.
- Production: The model is currently being produced, and generally available for purchase and sampling.
- Last Time Buy: The model has been scheduled for obsolescence, but may still be purchased for a limited time.
- Obsolete: The specific part is obsolete and no longer available. Other models listed in the table may still be available (if they have a status that is not obsolete).
For detailed drawings and chemical composition please consult our Package Site
- Commercial: 0 to +70 degrees Celsius
- Military : -55 to +125 degrees Celsius
- Industrial: Temperature ranges may vary by model. Please consult the datasheet for more information.
- Automotive: -40 to +125 degrees Celsius
Sample availability may be better than production availability. Please enter samples into your cart to check sample availability.
*The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
**Sample availability may be better than production availability. Please enter samples iinto your cart to check sample availability.

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