Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > Sensors/MEMS

IR reflective switch operates in dusty environs

Posted: 25 Aug 2006 ?? ?Print Version ?Bookmark and Share

Keywords:TT electronics? OPTEK Technology? infrared switch? OPB732?

OPTEK Technology's OPB732 reflective IR switch

TT electronics OPTEK Technology announced the development of a long distance infrared switch capable of more than one inch reflective distance. The OPB732 reflective switch has an infrared LED and phototransistor and uses an opaque housing to reduce the sensor's ambient light sensitivity.

The device suits non-contact reflective object sensing circuits in equipment security, machine safety, assembly line and machine automation, as well as door and end-of-travel sensing applications, the company said.

"While an object is in the path of the device, light from the LED will be reflected back to the housing, irradiating the surface of the phototransistor," explained Alan Bennett, sales and marketing VP at OPTEK Technology. "Both the emitter and sensor are protected by a clear window, which allows the device to operate in dusty environments, such as those in industrial and automotive applications."

When infrared light strikes the phototransistor, it becomes forward biased and is considered to be in the "on" state, providing an IC(ON) current proportional to the light striking the phototransistor, added Bennett. When the infrared light from the LED is not reflected to the phototransistor, the device turns "off," minimizing the IC(ON) current.

The OPB732 Series light emitting diode features an 850nm wavelength and a power dissipation of 100mW. Maximum forward current is 50mA and maximum forward voltage is 1.8V (If=20mA). Reverse DC voltage is 3V, with reverse current of 100?A (Vr=2V). Electrical performance of the output phototransistor is characterized at collector-emitter voltages of 30V, collector DC current of 50mA, and power dissipation of 100mW. Operating temperature range for the long distance reflective switch is -40C to 85C.

The OPB732 Series assembly is offered with either PC board through hole pins or 24-inch 26 AWG wires. The phototransistor can be configured as a common collector or common emitter device.

Pricing for the OPB732 reflective switch is $2.97 each in quantities of 1,000. Lead time is from 8 to 10 weeks if stock is not available.

Article Comments - IR reflective switch operates in dus...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top