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10 years, 6 months ago.
Light Sensors
How can you attach light sensors to LPC1768?
3 Answers
10 years, 6 months ago.
Nikki,
A simple idea would be to put a CDS photocell on one of the Analog-In pins. The CDS cell connected to 3.3V and the Analog-In pin together with a 10k resistor connected to ground and the same Analog-In pin. You may have to play around with the 10k value, depending on the CDS part you use.
...kevin
10 years, 6 months ago.
That's a wide open question... Much depends on what kind of sensor you want to use and what you want to measure about the light.
Sensor options include: photo transistor or diode, CDS cell, PIN photo diode, any number of TAOS light-to-something sensors.
Do you need to differentiate bright from dark? Or do you need to measure a continuous range of light values? Do you only need relative but finely graded light values or do you need to know absolute values (like for exposing film/sensors for photography)?
9 years, 12 months ago.
What connections with the ARM board do we use to differentiate between light and dark using a CdS photocell? We are looking for HIGH (when bright) and LOW (when dark) inputs only.