Plessey Semiconductors has designed a heart rate monitor demonstration using its EPIC sensor technology.
The EPIC sensor comes in the same size as of a wristwatch and does not require a chest strap or second sensor at the end of a cable that could be easily lost or damaged. This reference design shows that personal monitoring and pulse measuring of ECG signals are simple and easy.
The device straps to the wrist with a sensor electrode on the rear of the device in permanent contact with the wrist and the second electrode is on the front of the device. Touching this top electrode with a finger from the opposite hand enables the device to collect the heart signals.
"Our EPIC technology really makes heart monitoring so much simpler," explained Plessey's EPIC programme director, Dr Paul James. "Just two small contacts and no gels. This is ideal for the sports and fitness market where people want to measure more than just their heart rate when exercising for display either on the device or via a Bluetooth link to a mobile phone, tablet or PC. The data gathered is accurate enough that it can provide detailed ECG signals with the appropriate signal processing, including precise pulse rate and pulse rate variation. This opens up the possibility of estimating key aerobic performance parameters such as VO2max."
Plessey has also designed a version to provide continuous heart monitoring. This device straps to the upper arm and has two contacts on the inside of the strap. These are positioned such that the electrical cardiac signals are out of phase to give a strong differential signal to noise ratio so that unwanted noise artefacts from other muscles can be easily filtered out to give a detailed ECG trace.
Plessey' EPIC sensor technology is a sensor technology that measures changes in an electric field in a similar way to a magnetometer detecting changes in a magnetic field. The EPIC sensor used requires no physical or resistive contact to make measurements.
Plessey will be demonstrating these two reference designs on their booth 627 at the Chicago sensors expo show in June 6-7, 2012
Application notes are available at www.plesseysemiconductors.com/products/epic/applications/