New Vishay high-speed PIN photodiode enables improved biosensor performance, slim design for wearables

Figure 1: The VEMD8081 ideal for optical heart rate detection in wearable devices. New Yorker ElectronicsNew Yorker Electronics has added the new Vishay Semiconductors VEMD8081 high-speed and high-sensitivity PIN photodiode with enhanced sensitivity for visible light. The Vishay PIN photodiode provides increased photocurrent of 33 µA in a 4.8 mm x 2.5 mm SMD package with a 5.4 mm² sensitive area detecting visible and near infrared radiation.

Designed at a slim 0.48 mm height, the device is ideal for optical heart rate detection in wearable devices such as fitness trackers and smartwatches when placed between two pulsing green LEDs. They are also used in SpO2 measurement in medical monitors when combined with red and infrared emitters.

Figure 2: Vishay VEMD8081. Source: New Yorker ElectronicsThe new Vishay VEMD8081 offers 15% greater reverse light current than its predecessor, the Vishay VEMD8080, while maintaining the same package dimensions. It utilizes Vishay’s proven wafer technology to detect visible and near infrared radiation. New Yorker Electronics is distributing the new device to offer designers a drop-in replacement that can improve performance by increasing signal output, or extend battery life by reducing LED current.

The VEMD8081’s rectangular shape maximizes the area of the photodiode receiving reflected light, eliminating the wasted area typically found in square photodiodes. For heart rate measurement in wearable devices, the light reflected off the skin is received by the photodiode and converted to an output current, with the device’s increased sensitivity enabling more accurate measurements.

Features and benefits:

• Figure 3: The Vishay VEMD8081. Source: New Yorker ElectronicsEnhanced sensitivity to visible and infrared light
• Rectangular 4.8 mm x 2.5 mm top-view, surface-mount package with a low 0.48 mm profile
• Typical reverse light current of 33 µA
• Radiant-sensitive area measuring 5.4 mm²
• Wide spectral range from 350 nm to 1100 nm
• Fast switching times and low capacitance of 50 pF enable high sampling rates
• ± 65° angle of half-sensitivity
• Temperature range of -40° C to 85° C
• 840 nm wavelength of peak sensitivity
• RoHS-compliant, halogen-free and Vishay green
• Moisture sensitivity level (MSL) of 3 in accordance with J-STD-020 for a floor life of 168 hours
• Appropriate design for high-speed photo detector and wearables applications

Figure 4: VEMD8081 dimensions. Source: New Yorker Electronics

Samples and production quantities of the VEMD8081 are available now, with lead times of 10 weeks. New Yorker Electronics is a franchise distributor for Vishay and supplies the full line of Vishay Optoelectronics including optocouplers, optical sensors, seven-segment displays, infrared receivers, solid-state relays, LCDs, visible LEDs, infrared emitters, plasma displays, photo detectors, IrDA transceivers and infrared touch panels.

About New Yorker Electronics

New Yorker Electronics is a certified franchised distributor of electronic components, well known for its full product lines, large inventories and competitive pricing since 1948. It is an AS9120B and ISO 9001:2015 certified source of passive components, discrete semiconductors, electromechanical devices, Flash and DRAM modules, embedded board solutions, power supplies and connectors, and operates exclusively at heightened military and aerospace performance levels. New Yorker Electronics operates in strict accordance with AS5553 and AS6496 standards in its everyday procedures to thwart the proliferation of counterfeit parts. It is a member of ECIA (Electronics Component Industry Association) and of ERAI (Electronic Resellers Association International).