Features and Benefits
- 16-bit resolution with no missing codes
- 4-channel (AD7682)/8-channel (AD7689) multiplexer with choice of inputs
- Unipolar single-ended
- Differential (GND sense)
- Throughput: 250 kSPS
- INL: ±0.4 LSB typical, ±1.5 LSB maximum (±23 ppm or FSR)
- Dynamic range: 93.8 dB
- SINAD: 92.5 dB at 20 kHz
- THD: −100 dB at 20 kHz
- Analog input range: 0 V to VREF with VREF up to VDD
- Multiple reference types
- Internal selectable 2.5 V or 4.096 V
- External buffered (up to 4.096 V)
- External (up to VDD)
- Internal temperature sensor (TEMP)
- Channel sequencer, selectable 1-pole filter, busy indicator
- No pipeline delay, SAR architecture
- Single-supply 2.3 V to 5.5 V operation with 1.8 V to 5.5 V logic interface
- Serial interface compatible with SPI, MICROWIRE, QSPI, and DSP
- Power dissipation
- 3.5 mW at 2.5 V/200 kSPS
- 12.5 mW at 5 V/250 kSPS
- Standby current: 50 nA
- Low cost grade available
- 20-lead 4 mm × 4 mm LFCSP package
- 20-lead 2.4 mm × 2.4 mm WLCSP package
The AD7682/AD7689 are 4-channel/8-channel, 16-bit, charge redistribution successive approximation register (SAR) analog-to-digital converters (ADCs) that operate from a single power supply, VDD.
The AD7682/AD7689 contain all components for use in a multichannel, low power data acquisition system, including a true 16-bit SAR ADC with no missing codes; a 4-channel (AD7682) or 8-channel (AD7689) low crosstalk multiplexer that is useful for configuring the inputs as single-ended (with or without ground sense), differential, or bipolar; an internal low drift reference (selectable 2.5 V or 4.096 V) and buffer; a temperature sensor; a selectable one-pole filter; and a sequencer that is useful when channels are continuously scanned in order.
The AD7682/AD7689 use a simple serial port interface (SPI) for writing to the configuration register and receiving conversion results. The SPI interface uses a separate supply, VIO, which is set to the host logic level. Power dissipation scales with throughput.
The AD7682/AD7689 are housed in a tiny 20-lead lead frame chip scale package (LFCSP) and 20-lead wafer level chip scale package (WLCSP) with operation specified from −40°C to +85°C. The AD7689 includes an extended temperature range model with specifications guaranteed to a maximum temperature (TMAX) of +125°C.
- Multichannel system monitoring
- Battery-powered equipment
- Medical instruments: ECG/EKG
- Mobile communications: GPS
- Power line monitoring
- Data acquisition
- Seismic data acquisition systems
- Process control
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 (1)
The EVAL-AD7682EDZ is a fully featured evaluation Kit for the AD7682. This board operates in stand alone mode or in conjunction with the Converter Evaluation and Development board, EVAL-CED1Z . When operated with the Converter Evaluation and Development board, software is provided enabling the user to perform detailed analysis of the ADC's performance. This software includes the technical note describing the operation and set up of the evaluation board in standalone operation or when operated with the Converter Evaluation and Development board.
Software & Systems Requirements
Tools & Simulations
AD7682 Companion Parts
Recommended Digital Isolators
- For SPI Interface, lowest power, 2.5 kVrms isolation: ADUM1401.
- For SPI Interface, enhanced system-level ESD performance, 2.5 kVrms isolation: ADUM3401.
- For SPI Interface, smallest package, low voltage I/O (1.8 V to 5.5 V): ADUM3481.
- For SPI Interface, low power, 5.0 kVrms isolation: ADUM4401.
Recommended Driver Amplifiers
Recommended External Voltage References
- For low drift and lower cost sensitive applications: ADR440.
- For low drift and high current output applications: ADR430.
Recommended Voltage Regulators
Product Selection Guide (1)
Technical Articles (3)
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.
Sample & Buy
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.