Overview
Features and Benefits
- 18-bit resolution with no missing codes
- Throughput: 400 kSPS
- INL: ±0.75 LSB typ, ±1.5 LSB max
(±6 ppm of FSR) - Dynamic range: 102 dB @ 400 kSPS
- Oversampled dynamic range: 125 dB @ 1 kSPS
- Noise-free code resolution: 20 bits @ 1 kSPS
- Effective resolution: 22.7 bits @ 1 kSPS
- SINAD: 101.5 dB @ 1 kHz
- THD: −125 dB @ 1 kHz
- True differential analog input range:
±VREF0 V to VREF with VREF up to VDD on both inputs - No pipeline delay
- Single-supply 5 V operation with 1.8 V/2.5 V/3 V/5 V logic interface
Product Details
The AD7690 is an 18-bit, successive approximation, analog-to-digital converter (ADC) that operates from a single power supply, VDD. It contains a low power, high speed, 18-bit sampling ADC with no missing codes, an internal conversion clock, and a versatile serial interface port. On the CNV rising edge, it samples the voltage difference between the IN+ and IN− pins. The voltages on these pins swing in opposite phase between 0 V and REF. The reference voltage, REF, is applied externally and can be set up to the supply voltage.
The power of the AD7690 scales linearly with the throughput.
The SPI-compatible serial interface also features the ability, using the SDI input, to daisy-chain several ADCs on a single, 3-wire bus and provides an optional busy indicator. It is compatible with 1.8 V, 2.5 V, 3 V, or 5 V logic, using the separate VIO supply.
The AD7690 is housed in a 10-lead MSOP or a 10-lead QFN (LFCSP) with operation specified from −40°C to +85°C.
APPLICATIONS
- Battery-powered equipment
- Data acquisition
- Seismic data acquisition systems
- DVMs
- Instrumentation
- Medical instruments
Product Categories
Markets and Technologies
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (2)
Documentation
Application Notes (1)
Tested Product Combinations (1)
Software & Systems Requirements
Tools & Simulations
Precision ADC Driver Tool
The Precision ADC Driver Tool is a web application that simulates the performance of precision ADC and driver combinations. Potential issues with driver selection, kickback settling, and distortion are flagged, and design tradeoffs can be quickly evaluated. Simulations and calculations include system noise, distortion, and settling of the ADC input

Product Recommendations
AD7690 Companion Parts
Recommended Digital Isolators
- For SPI Interface, enhanced system-level ESD performance, 2.5 kVrms isolation: ADUM3401.
- For SPI Interface, low power, 5.0 kVrms isolation: ADUM4401.
- For SPI Interface, lowest power, 2.5 kVrms isolation: ADUM1401.
- For SPI Interface, smallest package, low voltage I/O (1.8 V to 5.5 V): ADUM3481.
Recommended External Voltage References
Recommended Driver Amplifiers
- For high frequency, low noise, low distortion applications: ADA4897-1, AD8021.
- For precision, low power, low distortion applications: ADA4841-1, ADA4940-1, ADA4941-1.
- For low frequency, precision, low bias current applications: ADA4627-1, ADA4610-2, AD8476.
Reference Materials
Tutorials (1)
Technical Articles (2)
Rarely Asked Questions (1)
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
PCN-PDN Information
Sample & Buy
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Sampling:
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Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.