Infrared sensor modules operate reliably even in direct sunlight

Vishay has launched two infrared (IR) sensor modules which produce robust operation in direct sunlight, while providing enough sensitivity for use in light barrier applications. The surface-mount TSSP93038DF1PZA and leaded TSSP93038SS1ZA, which offer typical irradiance of 1.3 mW/m², are supplied in compact Minimold packages. 

Unlike high-sensitivity fixed-gain IR sensor modules, which require an attenuator such as dark cover glass, apertures, or sunshades to protect them against interference from sunlight, the TSSP93038DF1PZA and TSSP93038SS1ZA have controlled sensitivity which allows them to operate in full sunlight without generating unwanted pulses. 

For short-range applications such as presence and proximity detection, the sensors’ reduced sensitivity eliminates the need for extremely low forward current at the emitter, which can lead to unstable intensity at the output. 

The TSSP93038DF1PZA and TSSP93038SS1ZA can perform proximity sensing at a range of up to 1 m. Range is up to 11 m in light-curtain applications when used with the Vishay TSAL6100 IR emitting diode operating at a forward current of 100 mA. Longer ranges can be achieved by using an emitter with a narrower focus, such as the Vishay VSLY5940, or by increasing the forward current to the emitter. 

These IR sensor modules are suitable for a wide range of proximity and presence detection use cases, including: 

• Vicinity switches
• Presence detection for traffic control lights and parking lots, and gateway access
• Water level detection
• Light barriers for sports racing and robotic lawnmowers 
• Reflective sensors for hand dryers, towel and soap dispensers, water faucets, toilets, vending machine fall detection, and security and pet gates