Single-Chip Opto Device Converts Light To Voltage December 2004 Issue Published Date: January 06, 2005
Combining the components of a typical discrete optoelectronic solution—photodiode, transimpedance amplifier and gain setting resistors—the single-chip TSL12/13/14 devices sense light and convert it to a voltage. Since all three elements are mounted on a single die, board space and noise are minimized. They provide an analog voltage proportional to light intensity. Each device is designed to meet a system’s low, middle or high range responsivity and rise-time performance, depending whether high sensitivity or high speed is more important for the application. The TSL12 has the greatest responsivity at 246 mV/µW/cm2 but the slowest rise time at 64 µs. The TSL14’s responsivity is just 16 mV/µW/cm² but rise time is much faster at 4 µs. Operating voltage is in the range of 3V to 5V and the spectral sensitivity range is 350 to 1,050 nm for all devices. Typical supply current is 1.1 mA and the operating temperature range is -25°C to +85°C. They are supplied in a clear plastic 3-lead through-hole package and a plastic side-looker package. Pricing for all three is $0.59 each/1,000. TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS INC., Plano, TX. (972) 673-0759.
