>        The other interesting chip is the TSL23x series of light to frequency
>converters.  I do not have an appropriate data book so the question is
>what is the difference between the TSL230 and TSL235?  What TI book
contains this information?

The 235 is a fixed output version of the 230.  The 230 is pin programmable
for output frequency scaling and light sensitivity.

The 235 is 3 lead 230 device with the sensitivity and output scaling preset
by TI.  Vcc, Gnd, and Fout about 10Hz to 500kHz 50% duty square wave.

All of TI optic sensors are described in the TI  Intelligent Optic Sensor
databook.  I don't have the Book # with me but I cat get it at work if you
need it.

TI's web site also contains the information.
--
Richard A. Smith        "I don't believe in magic, but I can simulate it."
ras2@tant.com   - Phil Kinkade