ADI AD7689

AD7689 General Description

The AD7682 and AD7689 are advanced analog-to-digital converters (ADCs) designed for precision data acquisition systems. These 16-bit SAR (Successive Approximation Register) ADCs offer exceptional performance and versatility, making them ideal for a wide range of applications.

The AD7682 provides 4 channels, while the AD7689 offers an expanded 8-channel configuration. This flexibility allows for efficient multiplexing and channel selection.

Both ADCs offer true 16-bit resolution with no missing codes, ensuring accurate and reliable data conversion.

The low crosstalk multiplexer in the AD7682/AD7689 supports various input configurations, including single-ended, differential, or bipolar. This flexibility is valuable for accommodating different sensor types.

These ADCs feature an internal reference voltage with selectable options of 2.5V or 4.096V, providing stable and precise reference levels for conversions.

Additional integrated components include a temperature sensor, a selectable one-pole filter, and a sequencer for efficient channel scanning.

The ADCs utilize a straightforward SPI interface for configuration and data retrieval. The SPI interface operates at a separate supply voltage (VIO), which can be adjusted to match the host logic level.

Power dissipation scales with the data throughput, ensuring efficient energy usage.

Both the AD7682 and AD7689 are available in compact packages, including a 20-lead lead frame chip scale package (LFCSP) and a 20-lead wafer-level chip scale package (WLCSP).

These ADCs are suitable for a wide temperature range, with operation specified from -40°C to +85°C. An extended temperature range model of the AD7689 is also available, with specifications guaranteed up to a maximum temperature (TMAX) of +125°C.

Pin configuration/ function description

Specifications

Features

High Resolution: Provides 16-bit resolution with no missing codes, ensuring accurate data conversion.

Multiplexer Options: Offers a 4-channel configuration in AD7682 and expands to an 8-channel multiplexer in AD7689, supporting various input options:

Unipolar single-ended
Differential (GND sense)
Pseudobipolar
Throughput: Capable of achieving a throughput of 250 kSPS, facilitating rapid data acquisition.

Excellent Linearity: Impressive integral nonlinearity (INL) performance with ±0.4 LSB typical and ±1.5 LSB maximum, equivalent to ±23 ppm of full-scale range (FSR).

Dynamic Range: Boasts a dynamic range of 93.8 dB, ensuring the capture of a wide range of signal amplitudes.

Signal-to-Noise Performance: High signal-to-noise and distortion ratio (SINAD) of 92.5 dB at 20 kHz, with total harmonic distortion (THD) of -100 dB at 20 kHz.

Flexible Input Range: Supports an analog input range from 0 V to VREF, with VREF scalable up to VDD.

Multiple Reference Options: Provides flexibility with multiple reference types, including internal selectable 2.5 V or 4.096 V, external buffered (up to 4.096 V), and external (up to VDD) references.

Internal Temperature Sensor: Includes an internal temperature sensor (TEMP), adding environmental monitoring capabilities.

Additional Features: Equipped with a channel sequencer, selectable 1-pole filter, and a busy indicator for enhanced functionality.

Low Latency: Utilizes a SAR (Successive Approximation Register) architecture with no pipeline delay, ensuring fast and accurate conversions.

Wide Voltage Range: Operates on a single supply voltage ranging from 2.3 V to 5.5 V, with a logic interface compatible with 1.8 V to 5.5 V.

Versatile Serial Interface: Compatible with various serial interface standards, including SPI, MICROWIRE, QSPI, and DSP.

Power Efficiency: Low power dissipation, with options like 3.5 mW at 2.5 V/200 kSPS and 12.5 mW at 5 V/250 kSPS. Offers a standby current of 50 nA for power-saving applications.

Cost-Effective Variant: Available in a low-cost grade for budget-conscious applications.

Compact Packages: Housed in space-saving 20-lead packages, including a 4 mm × 4 mm LFCSP package and a 2.4 mm × 2.4 mm WLCSP package.

Equivalent Parts

Absolute maximum ratings

Application

Multichannel System Monitoring: Used to monitor multiple channels simultaneously, making it ideal for systems that require continuous data monitoring.

Battery-Powered Equipment: Well-suited for battery-operated devices where power efficiency is critical.

Medical Instruments (ECG/EKG): Ensures precise data conversion in medical equipment, particularly in electrocardiography (ECG or EKG) devices where accuracy is paramount.

Mobile Communications (GPS): Supports the data acquisition needs of mobile communication devices, including Global Positioning System (GPS) receivers.

Power Line Monitoring: Used in power grid monitoring systems to gather critical data for power management and optimization.

Data Acquisition: Provides accurate analog-to-digital conversion for data acquisition systems across various industries.

Seismic Data Acquisition Systems: Enables precise data collection and analysis in seismic applications, where even slight variations in signals are significant.

Instrumentation: Used in various instrumentation systems that require high-resolution data conversion, ensuring measurement accuracy.

Process Control: Plays a role in process control systems, contributing to the control and monitoring of industrial processes.

AD7689 Evaluation Board

https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/eval-ad7689.html

https://www.ovaga.com/blog/transistor/ad7689-evaluation-board-eval-ad7689-and-eval-ad76muxcbz

AD7689 Application Notes

https://www.analog.com/media/en/technical-documentation/application-notes/ee395v01.pdf

AD7689 C Code

https://github.com/analogdevicesinc/no-OS/blob/master/drivers/adc/ad7689/ad7689.c

AD7689 Conversion Pin 11

https://www.analog.com/media/en/technical-documentation/data-sheets/ad7682_7689.pdf

Related Parts

Connection Diagram

Dimensions

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AD7689 Evaluation Board: EVAL-AD7689 and EVAL-AD76MUXCBZ

Specifications