The Texas Advanced Optical Systems (TAOS) TSL230R sensor precisely measures light using an array of photodiodes, with an output of digital square waves. The TSL230R has an input dynamic range of 160dB; that is, it can measure light over a range of 100,000,000-to-1.

The TSL230R programmable light-to-frequency converter combines a configurable silicon photodiode and a current-to-frequency converter on single monolithic CMOS integrated circuits. The output can be either a pulse train or a square wave (50% duty cycle) with frequency directly proportional to light intensity. The sensitivity of the device is selectable and the output frequency can be scaled by one of four preset values. An output enable (OE) is provided that places the output in the high-impedance state for multiple-unit sharing of a microcontroller input line.

Features:

• High-resolution conversion of light intensity to frequency with no external components
• Programmable sensitivity and full-scale output frequency
• Communicates directly to a BASIC Stamp or SX microcontroller
• Absolute output frequency tolerance of +/- 20%
• Nonlinearity error (typically 0.2% at 100kHz)
• Stable over wide variety of temperatures

Downloads and Resources:
TSL230R v1.0 Documentation (.pdf)
BASIC Stamp Code for TSL230R (.zip)
N&V column "Look into the 'Eye from TI'" #21 (.pdf)
N&V code "Look into the 'Eye from TI'" #21 (.zip)
BASIC Stamp Experiments using the TSL230 by Mark Hughes (.pdf)
Data Sheet(.pdf)