Temperature sensor

Able to precisely measure temperature, hyper-accurate digital temperature sensors from ams OSRAM have raised the bar on monitoring body temperature.

Health monitoring devices give valuable insights into many bodily functions – without medical appointments or invasive procedures. Equipped with sensors, they measure blood pressure, heart rate, or body temperature. These days, consumers are learning to what extent they can rely on such measurements, not only for wellness and fitness using consumer devices like smart watches, wrist bands, or earbuds, but also to manage or monitor known or new health conditions, often using medical-grade wearable devices that must meet the highest standards of accuracy and reliability over continuous, long-term use. This is driving both market demand and innovation for such devices, especially where temperature is a cost-effective first indicator of conditions such as the COVID-19 virus.

One prevalent condition is diabetes. Around 422 million adults globally suffer from diabetes and must continually monitor their blood sugar to minimize long-term potential serious damage to the heart, blood vessels, eyes, kidneys, and nerves. Today, Continuous Glucose Monitoring (CGM) systems are available as medical patches that prick the skin to measuring the glucose value of the blood over a period of 30-90 days. These devices must provide accurate measurement despite influencing factors of the immediate environment. So, additional sensors, like a temperature sensor, can help to reduce environmental impacts and improve performance of the CGM-System.

However, one of the most complex engineering problems to solve is the accurate monitoring of health conditions. For the manufacturers of these devices, there are many application and design challenges that must first be overcome.


Meeting the complex challenges of monitoring body temperature

ams OSRAM is helping manufactures to resolve each of these challenges with the most sophisticated solution currently available. The hyper-accurate digital temperature sensor family from ams OSRAM can precisely measure body and skin temperature (the AS6221 offers 0.09°C accuracy over a temperature range of 20-42°C) even for critical healthcare applications. Because of this, the AS6221 helps customer designs obtain medical certification, such as EN 12470-3, required for all medical thermometers in the European Union. Watch the benefits in our video:
 


In wearables, battery-driven patches, and even medical-grade solutions, sensors must be small enough for the device to be comfortable to wear for personal health monitoring – especially where designs call for multiple sensors and other components (The AS6221 is just 1.5mm x 1mm WLCSP). Thermal conduction can be an issue with many other sensor options: the housing of the digital sensor system must be designed to conduct the temperature to the sensor without loss; while it must account for heat generated by any other components to remain accurate, for example by isolation method or using further temperature sensors to measure any thermal influences caused.


In all battery-powered mobile electronic devices, power efficiency is a must – especially for long-term, continuous monitoring – and this family of sensors has outstanding low power consumption. In operation mode the AS6221 consumes only 6µA at four measurements/sec (although up to 27 measurements/sec is possible). In standby mode, this falls to 0.1µA.

These ams OSRAM technologies support the development of health monitoring devices by enabling reliable measurement. The AS6221 is a complete digital sensor system requiring no calibration or linearization. The family enables many different system designs and the AS6221 achieves optimal results through the shortest possible thermal connection and reduced thermal capacity of the PCB. The sensor and its digital interface – with the option of using multiple sensors on one bus – offers easy integration into systems and smart interaction with machine–learning algorithms. An integrated alert functionality triggers an interrupt to the external micro controller when a temperature threshold is exceeded.

The ams OSRAM digital temperature sensors meets the highest quality standards to provide you with exceptional reliability over the lifetime of your product. If you would like to learn more, please ask for an evaluation or demo kit, or see our new temperature sensor video.