Ams Launches New AS705x Analog Front End Series

     Ams announced the launch of the AS705x, its first pure integrated circuit vital signs sensor family. Emath OSram's first-generation biosignal converters offer manufacturers great flexibility, a highly customised optical front end combined with an energy efficient design and compact shape, ideal for applications where circuit board space is limited, such as headphones, smartwatches or smart patches.

     The AS7050 is the first biosignal sensor in EMath OSram's new product line that enables end users to capture biosignals such as heart rate measurement (HRM) and skin resistance (GSR). With the help of two ADC (analog-to-digital converter) channels and an embedded ECG low-noise analog front end, the AS7050 can perform both optoelectronic volumetric pulse wave pattern (PPG) and electrocardiogram (ECG) measurements simultaneously. Customers who require smaller optics and do not require an ECG can choose the AS7056 or AS7057 series.

     "The AS7056 and AS7057 are the smallest AFEs currently available for vital sign monitoring, with chip sizes of approximately 1.7mm x 1.7mm," said Markus Arzberger, MD, Head of the Vital Sign Monitoring Applications Business Unit at Emais Osram. Amys Osram's new biosensor can be used to measure vital signs in PPG-based listening devices or accessories. "These two products allow customers to combine advanced analog-to-digital conversion processes to develop extremely small, highly customized optical fronts."

      Optical systems can be used to noninvasively measure vital signs such as heart rate variability. PPG (photoplethysmography) is the most common optical system solution that can be used for heart rate measurement. Green light enters the body's tissues, where it is scattered and partially absorbed by the blood. A small fraction of the emitted light is scattered back to the photodiode and detected with an integrated circuit. Since blood volume varies at heart rate, light absorption and photodiode signals are modulated accordingly by heart rate.

      The AS7050 offers up to eight LED driver outputs, sampling up to six photodiode inputs, and support for external electrodes. The AS7056 and AS7057 support up to three photodiodes and three EMitters, while one of the emitters in the AS7056 is a VCSEL (Vertical Resonant Cavity Surface Laser) driver. This provides high flexibility for various emitter and photodiode Settings in different applications.