Vishay OPTO Squad

Part 2 of “A Brief History and Evolution of Automotive Transmissive Sensors”

The TCPT- and TCUT1300X01 Period

Automotive customers needed a transmissive sensor that could operate at higher temperatures and was qualified to AEC-Q101 standards. The molding compound of the emitter and detector limited the operating temperature. Based on the techniques used in Origami, Vishay designed a lead-frame based, custom formed sensor that used emitter and detector chips without lenses. TCUT1300x01With a gap of 3.0mm and tightly controlled chip placement, the operating temperature increased from a maximum of +85°C to +105°C.  Following the Orwellian theory of one detector good, two detectors better, Vishay created a transmissive sensor with two detector windows. With two detectors, steering angle sensors could not only detect a code wheel but could also determine direction and speed, which is critical input to electronic stability control units.

The advantage of this sensor’s construction over standard slotted interrupters includes:

  • Tighter tolerances of package outline dimensions and contact pads
  • Tighter tolerance of optical axis
  • Better co-planarity of contact pads for mounting to PCB

 The TCPT- and TCUT1350X01 Period

Ever-demanding automotive customers needed the sensor to operate at still higher temperatures, to work in near-engine compartments and harsh environments up to 125°C. With some inspired design changes, Vishay was able to manufacture transmissive sensors that met this specification. In addition, the typical output current was increased from 0.6 mA to 1.6 mA.

Tune in for Part – 3: The TCPT- and TCUT1600/30X01 Period

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.


This entry was posted on November 6, 2015 by in Articles, Infrared Emitter, Photo Detectors.
%d bloggers like this: