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Adafruit GA1A12S202 Log-Scale Analog Light Sensor

Code: N53DQ

  • Output voltage increases with light on the sensor
  • Logarithmic response not only gives more sensitivity in low light, its also almost impossible to ""max-out"" the sensor
  • Dynamic range of 3 to 55,000 Lux

Product details

Adafruit GA1A12S202 Log-Scale Analog Light Sensor

• Output voltage increases with light on the sensor• Logarithmic response not only gives more sensitivity in low light, its also almost impossible to ""max-out"" the sensor• Dynamic range of 3 to 55,000 Lux• Use indoors and outdoors without needing to recalibrate!

Upgrade a project that uses a photocell with the GA1A12S202 analogue light sensor. Like a CdS photo-cell, the sensor does not require a microcontroller, the analog voltage output increases with the amount of light shining on the sensor face. This sensor has a lot of improvements that make it better for nearly any project. The biggest improvement over plain photocells is a true log-lin relationship with light levels. Most light sensors have a linear relationship with light levels, which means that they're not very sensitive to changes in darkened areas and 'max' out very easily when there's a lot of light. Sometimes you can tweak a resistor to make them better in dark or bright light but its hard to get good performance at both ends. This sensor is logarithmic over a large dynamic range of 3 to 55,000 Lux, so it has a lot of sensitivity at low light levels but is also nearly impossible to ""max out"" so you can use it indoors or outdoors without changing code or calibration. Since the sensor is fabricated on a chip, there are also fewer manufacturing variations, so you won't have to calibrate the sensor from one board to another. Using the sensor is easy as pie: connect the Vin to 2.3-6VDC, Gnd to ground and measure the analogue output on OUT. It will range up to 3V (at extremely bright outdoor sunlight). On an Arduino, just use analogRead() with the OUT pin connected to an analogue pin.

On this breakout there’s a 68KO resistor from OUT to ground to turn the current into a voltage.

Can I use this with conductive thread? 

Asked by: Rosel
Please be assured, if you have any queries with regards to specific products from our stock, we will be more than happy to assist. However, it is important to note that as a retail only company we are unable to assist with any design projects or queries, or advise on specific products that may be required for your purpose. Sorry we could not help resolve your query on this occasion.
Answered by: Dominic
Date published: 2015-11-24

What are the overall dimensions of the unit [mm please] - height / width / thickness ?
Asked by: Anonymous
Specifications: Power with 2.3-6V Onboard 68K load resistor for max 3V analog output 0.2 grams 0.4" x 0.5" x 0.06" (10mm x 13mm x 1.5mm) 0.1" (2.5mm) mounting hole
Answered by: PC
Date published: 2016-03-25
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Bulk Prices

Item code Item name Quantity Price
N53DQ Adafruit GA1A12S202 Log-Scale Analog Light Sensor (1+) £4.99

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