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NORWOOD, Mass.–(BUSINESS WIRE)–Analog
Devices, Inc.
(ADI) announced today a new electrochemical &
impedance measurement front end that enables the next generation of
vital sign monitoring devices and intelligent electrochemical sensors.
The AD5940
analog front end incorporates both potentiostat and electrochemical
impedance spectroscopy (EIS) functionality on a single chip, allowing
for sensor measurement in both time and frequency domains. The device
features integrated hardware accelerators for advanced sensor
diagnostics, best-in-class low noise for accurate sensor measurements
and is designed for wearable “always-on” applications. Compared to
traditional discrete solutions which pose limitations and require
multiple ICs to achieve similar performance, ADI’s single chip solution
offers advantages in terms of system accuracy and size flexibility to
measure 2-Lead, 3-Lead and 4-Lead electrochemical sensors. It’s an ideal
solution for applications, where high precision biological and chemical
sensing is mission-critical, such as industrial gas sensing, liquid
analysis, material sensing, vital signs monitoring, impedance
spectroscopy and disease management.

AD5940
The AD5940 is the lowest power, highest performance
Impedance and electrochemical front end with intelligent autonomous
control. The analog front end combines leading levels of integration and
performance for potentiostat and impedance-based electrochemical sensor
managements. The on-chip potentiostat allows for a host of standard
electrochemical-based measurement techniques, such as amperometric,
voltametric, or impedance measurements.

The AD5940 is designed to be used in healthcare-related bio-impedance
systems for both skin impedance and body impedance measurements, and
also to work with the AD8233
AFE in a complete bioelectric/biopotential measurement system.

The analog front end chip can measure Voltage, current and impedance.
The device consists of two potentiostat loops, a low bandwidth loop with
ability to generate AC signals up to 200 Hz and a high bandwidth loop
with ability to generate AC signals up to 200kHz. The ultra-low power
Potentiostat consumes 6.5uA in biased mode.

The AD5940 measurement channel features a 16-bit, 800 kSPS, multichannel
successive approximation register (SAR) analog-to-digital converter
(ADC) with input buffers, a built in anti-alias filter (AAF), and a
programmable gain amplifier (PGA). The ADC features an input voltage
range of ±1.35 V. An input mux before the ADC allows the user to select
an input channel for measurement. These input channels include multiple
external current and voltage inputs, and internal voltage channels. The
internal channels enable on chip diagnostic measurements of the internal
supply voltages, die temperature, and reference voltages.

The AD5940 measurement blocks can be controlled via direct register
writes through the Serial Peripheral Interface (SPI) interface, or
alternatively, by using a pre-programmable sequencer, which provides
autonomous control of the AFE chip. 6 kB of static random access memory
(SRAM) is partitioned for a deep data first in, first out (FIFO) and
command memory. Measurement commands are stored in the command memory
and measurement results are stored in the data FIFO. A number of FIFO
related interrupts are available to indicate state of the FIFO.

Pricing & Availability

                         
Product    

Sample
Availability

   

Production
Availability

   

Price per 1000-
unit Quantity

    Package

AD5940

    Now     Released     $4.17     3.6 mm × 4.2 mm, 56 ball WLCSP
               

About Analog Devices
Analog Devices is a leading
global high-performance analog technology company dedicated to solving
the toughest engineering challenges. We enable our customers to
interpret the world around us by intelligently bridging the physical and
digital with unmatched technologies that sense, measure, power, connect
and interpret. Visit http://www.analog.com

Read and subscribe to Analog Dialogue, ADI’s monthly technical
journal, at:
http://www.analog.com/analog-dialogue.html

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Contacts

Doug Dickinson
Analog Devices, Inc.
[email protected]