Compact Transmissive Switch Touts Infrared Sidelookers

By employing optical, noncontact switching technology, the QVE00033 phototransistor infrared transmissive switch is generally more reliable and power-efficient than contact switches. One key feature is the inclusion of miniature infrared sidelookers. The switch's small size and surface-mount package (the temperature-resistant black plastic housing measures 7.50 by 4.05 by 5.40 mm) suit it for noncontact switching applications in disk drives, card detectors, mice and trackballs, and motor and motion controllers. Surface-mounting eliminates through-hole pins or wire leads. Within the device, a gallium-arsenide (GaAs) LED faces a silicon phototransistor across a 2-mm gap with a 0.4-mm aperture. A daylight filter on the phototransistor improves immunity to ambient light. The device operates from −55°C to 100°C and features a reflow soldering temperature of 240°C peak. The QVE00033 costs $0.65 each in 1000-unit quantities.