NPN phototransistors exhibit fast response times

Edited by the Electronicstalk editorial team Nov 10, 2005

TT Electronics' Optek Technology has developed a series of NPN silicon phototransistors in 1206 chip packages.

Providing design engineers with a miniaturised surface mount device for infrared detection in sensing applications, TT Electronics' Optek Technology has developed a series of NPN silicon phototransistors in 1206 chip packages.

Designated the OP520/OP521 Series, the surface mount devices exhibit response times of 15us with peak response to 880nm wavelength light.

"Design engineers working with infrared sensing systems now have the option of using these miniature surface mount photodetectors, enabling them to put the sensors virtually anywhere in their systems", said Dave Birtalan, Vice-president of Optek Technology's components business unit.

"Their fast response times and high sensitivity make them ideal for machine automation applications, miniature optical encoders, and other high speed noncontact position sensing systems".

The OP520 and OP521 Series devices are silicon NPN phototransistors designed to detect 880nm wavelength infrared light.

Both devices are packaged in a 1206 chip with a flat moulded lens; the OP520 features an opaque lens to shield it from ambient light, while the OP521 lens is water clear, giving it a wider response range.

According to Birtalan, the OP520/OP521 Series IR detectors are part of a major expansion of Optek's surface mount infrared components, which will include IR LEDs and silicon NPN phototransistors in 0805 and 1206 chip size packages; 1.9mm plastic packages, and PLCCs (plastic leadless chip carriers) in a variety of mounting styles and lense options.

Electrical performance of the OP520/521 Series is characterised at collector-emitter voltages of 30V, emitter-collector voltage of 5V, collector current of 20mA and power dissipation of 75mW at 25C.

They are RoHS-compliant, as well as compatible with high temperature (260C) lead free soldering processes, and are rated for operation from -25 to +85C.

The OP520/OP521 Series are designed to be mechanically and spectrally matched to Optek's OP250 Series surface mount infrared LEDs.

Typical pricing for the OP520/OP521 Series phototransistors starts at $0.20 each in quantities of 1000 pieces, with samples available immediately.

Production quantity lead times are from stock to 8 weeks, if not available in stock.