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GA1A12S202 Log-scale Analog Light Sensor

SKU: ADA1384

$6.95 AUD, inc GST
$6.32 AUD, exc GST

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GA1A12S202 Log-scale Analog Light Sensor
6.95 AUD

SKU: ADA1384

$6.95 AUD, inc GST
$6.32 AUD, exc GST
In stock, with a short lead time. 115 units dispatch in 4 to 7 days (in addition to the shipping method you choose). Our timing and stock is accurate. Delivery to you by Wed, 30th of Aug with Express Post within Australia.
Shipping Offer

Upgrade a project that uses a photocell with the GA1A12S202 analog 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 analog 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 analog pin. For more information including graphs, power consumption, etc check out the datasheet in the Tech Details tab. On this breakout Adafruit placed a 68KΩ resistor from OUT to ground to turn the current into a voltage.

GA1A12S202 Log-scale Analog Light Sensor (6:52)

Technical Details

GA1A1S202WP Datasheet and Adafruit Fritzing Library available in the product tutorial

  • 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

This product is listed in:

Documentation and Resources:
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Product Comments

We deliver Australia-wide with these options:

  • $3 for Small Items (4-6 days, not tracked, only available on selected small items)
  • $6.95 for Standard Post (2-4 days, tracked)
  • $8.32 for Express Post (1-2 days, tracked)
  • Pickup - Free! Only available to customers who live in the Newcastle region

International Orders - the following rates are for New Zealand and will vary for other countries:

  • $11.49 for Pack and Track (3+ days, tracked)
  • $16.50 for Express International (2-5 days, tracked)

If you order lots of gear, the postage amount might increment based on the weight of your order.

Our physical address:

Unit 18, 132 Garden Grove Parade
Adamstown
NSW, 2289
Australia

Please checkout our customer service page if you have other frequently asked questions such as "do we do purchase orders" (yes!) or "are prices GST inclusive" (yes they are!). We're here to help - get in touch with us to talk shop.