PIN Photodiodes Provide Reliable Signal Detection, Enable Slim Sensor Designs for Wearables

MALVERN, Pa. — To meet the need for reliable signal detection in wearable devices and medical and industrial applications, Vishay Intertechnology, Inc. broadened its optoelectronics portfolio with the introduction of two new high speed silicon PIN photodiodes that deliver enhanced sensitivity for visible light. Featuring infrared radiation suppression filters and black packages for an improved signal-to-noise ratio, the Vishay Semiconductors VEMD5510C and VEMD5510CF offer fast switching times and low capacitance in compact top-view, surface-mount packages.

Featuring a large radiant-sensitive area measuring 7.5 mm², the photodiodes offer sensitivity ranges from 440 nm to 700 nm for the VEMD5510C and 440 nm to 620 nm for the VEMD5510CF, with reverse light currents of 0.6 µA and 0.25 µA, respectively. The devices' on-chip suppression filters eliminate disturbances from non-visible light, while their black packages block unwanted lateral illumination. This results in spectral sensitivity of less than 5 % for wavelengths greater than 800 nm for the VEMD5510C and greater than 700 nm for the VEMD5510CF — closely matching that of the human eye.

The photodiodes released today are offered in small 5 mm by 4 mm packages with a low 0.9 mm profile to enable slim sensor designs. The devices are optimized for optical heart rate measurement in wearable devices such as fitness trackers and smart watches, as well as in medical biosensors connected to patient monitoring systems. In addition, the photodiodes provide high speed photo detection for flame detectors and ambient light sensing for display dimming or light adjustment functions.

The VEMD5510C and VEMD5510CF feature a ± 65° angle of half-sensitivity, an operating temperature range of -40 °C to +100 °C, and 550 nm and 540 nm wavelengths of peak sensitivity, respectively. RoHS-compliant, halogen-free, and Vishay Green, the photodiodes provide a moisture sensitivity level (MSL) of 4 in accordance with J-STD-020 for a floor life of 72 hours.

Samples and production quantities of the VEMD5510C and VEMD5510CF are available now, with lead times of eight weeks for large orders. Pricing for U.S. delivery only starts at $0.58 per piece.

For the latest in all things opto — articles, videos, and products — visit Vishay's Opto Squad blog site: www.vishayopto.com.