Infrared LEDs Suit Proximity Sensing
Fri, 02/04/2011 - 9:36am
A new series of high-performance infrared LEDs suited for proximity sensor applications is now available from ROHM Semiconductor . The SIM-030/031ST and SIM-040/041ST surface-mount IR LEDs feature a desirable IR wavelength technology providing peak output of 850/870 nm, compared to 950 nm for comparable devices. The 850/870 nm level is much closer to the peak wave sensitivity of phototransistors (sensors), thus achieving higher efficiency proximity sensing and energy savings of up to 66 percent, according to the company. The small package footprint and low-profile further enhance their application in cell phones and other portable devices. The SIM-030/031ST, the smaller of the two devices, has a 2.3 mm x 1.95 mm footprint and a height of 0.9 mm. With a forward current (IF) of 100 mA, the device delivers typical emission strength of 30 mW/sr (milliwatts per steradian). The slightly larger SIM-040/041ST (3.1 mm x 2.25 mm x 1.6 mm) provides 40 mW/sr, typical emission strength.