Healthcare industry booming and wearable smart watch market promising

In recent years, wearable devices such as smart bracelets and watches have been developing rapidly. This is mainly because modern people are valuing more exercise and the physiological data can be seen at any time to early detect any abnormal signs of body conditions. This paper will describe the AD8233 ECG biopotential signal conditioning module launched by ADI for you to learn about its functions and applications in healthcare and wearable smart watches.

Highly integration to simplify ECG device design

As society is aging, more and more people are valuing more their health care. Beside exercise and nutrition, if the body conditions can be monitored in real time, it will help to detect the signals of body condition and prevent any poor result. And it is just the reason for why the companies devoting in developing smart bracelets and watches business have achieved a rapid growth of revenues in the past several years.

The wrist is the most common position to wear a wearable device, on which we are used to wearing some ornaments. It is the reason for why there are so many products on the market like smart watches and wrist-wearing devices. Beside the wrists, the head is another preferable position to wear wearable devices. For example, the embedded sensors are integrated in forms like headphones and earbuds, etc. which are used to measure the body parameters including heart rate, oxygen saturation and temperature. The third position on body that can wear a device is the chest. The first generation of heart rate monitor was designed to wear with embracing a chest strap. However, it is preferable now to use a chest patch because wearing a strap is not very comfortable.

ADI captures this market demand and launches the AD8233 new-generation low energy-consumption bioelectrical analog front end (AFE). It is an integrated signal conditioning module suitable for the applications of ECG and other bio-potential measurements. It can be used to build a heart monitoring device that is smaller, lighter, more hidden and of extended battery life. The AD8233 AFE is a fully-integrated single-lead ECG front end designed into a compact and easy-to-use form.

Usually, developers need multiple independent components to design ECG front end which will increase the cost and design time. However, the highly-integrated and ready-to-use AD8233 AFE eliminates unnecessary cost and extra time, which helps the developers to launch a product to the market faster. Moreover, the super-small size of the AD8233 in 2.0mm x 1.7mm allows wearable healthcare devices to be built smaller, lighter and easier to wear.

For the users, it is very uncomfortable to wear a big, cumbersome and obtrusive monitor or even interfere with their daily lives. A long battery life can ensure the heart monitor will continuously perform so as to provide accurate data and it does not need to charge or replace the battery, which will interrupt the monitoring. Thus, this feature is vital. The power consumption of the AD8233 AFE is at a level of microamp, which will greatly extend battery life.

The AD8233 can be used to collect, amplify and filter the small biopotential signals under noisy conditions, for example, those signals generated due to motion or placement of electrode in the distance. With this design, its ultra-low power analog-digital converter (ADC) or embedded micro-controller can collect the output signals easily.

The AD8233 uses one two-pole, high-pass filter to remove the motion artifact and the electrode half-cell potential. Such filter couples closely with the architecture of the instrument amplifier and realizes large gain and high-pass filtering in a single stage which further saves the space and cost. With the help of one general-purpose operational amplifier, the AD8233 can form a three-pole, low-pass filter to remove more noise. The user can select the cut-off frequency of all the filters, being convenient to satisfy the demand of various applications. In order to improve the common mode rejection of the system line frequency and reduce other undesirable interferences, one RLD amplifier used to drive the lead is integrated in the AD8233.

The AD8233 also features fast restore which can shorten the duration at long-time stable tail of the high-pass filter. If an abrupt signal change causes amplifier pulsation (for example, leads off condition, etc.), the AD8233 will automatically adjust to a higher filter cut-off frequency. This function allows the AD8233 to recover rapidly, thus ensuring the measurement is implemented as soon as possible once the electrodes are connected to the object. The AD8233 is packaged in the form of WLCSP with 20 balls and will provide the optimal performance at the temperature between 0℃ and 70℃ and can operate between −40℃ and +85℃. It can be used in healthcare / activity heart rate monitor, portable ECG, wearable and remote health monitor, gaming peripherals and biopotential signal collection, for example, electromyography (EMG) or electroencephalogram (EEG), etc.

In order to help the customers to develop the related products, ADI also provides evaluation board, reference design, web-based filter design toolbox and Spice model for the AD8233 to help the users to design in and accelerate the product launch. The AD8233CB-EBZ evaluation board integrates a front end of the AD8233 heart rate monitor (HRM) and is assembled with various necessary components which are convenient for the initial evaluation of fitness applications. It consists of input, output, supplies and leads off detection terminals which can be routed to the test pins to simplify the connection. The switches and jumpers can be used to set the input bias voltage, shutdown (SDN), right leg drive shutdown (RLD SDN), fast restore (FR), DC/AC leads off detection modes. This evaluation board is designed with a 4-layer structure where the components are mounted only on the primary side and the rubber feet are provided on the secondary side to produce mechanical stability. In addition, the board layout is provided as a visual aid and reference design.

Featured Products



Related news articles

Latest News

Sorry, your filter selection returned no results.

We've updated our privacy policy. Please take a moment to review these changes. By clicking I Agree to Arrow Electronics Terms Of Use  and have read and understand the Privacy Policy and Cookie Policy.

Our website places cookies on your device to improve your experience and to improve our site. Read more about the cookies we use and how to disable them here. Cookies and tracking technologies may be used for marketing purposes.
By clicking “Accept”, you are consenting to placement of cookies on your device and to our use of tracking technologies. Click “Read More” below for more information and instructions on how to disable cookies and tracking technologies. While acceptance of cookies and tracking technologies is voluntary, disabling them may result in the website not working properly, and certain advertisements may be less relevant to you.
We respect your privacy. Read our privacy policy here