These chips came to mind... built in photodiodes (1x visible, 1 x infrared)=
, ADC,=20
drive external LED with programmable current (the Si1143 can drive 3 x LEDs=
=20
independently).

http://www.silabs.com/products/sensors/Pages/default.aspx

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Brent Brown, Electronic Design Solutions
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Hamilton 3200, New Zealand
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Fax: +64 7 849 0071
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eMail:  brent.brown@clear.net.nz



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