Product description
EK028 from Electrokit - Soldering kit. A simple light-activated night-light. The circuit consists of a photoresistor, a driver transistor, and a LED. The photoresistor, together with three 1 MΩ resistors, forms a voltage divider that controls the transistor. When the transistor starts conducting, current flows through the LED, which then lights up.
The the PCB forms a USB-A connector. It can be plugged into a USB port on a computer or directly into a USB charger in a wall socket. Two diodes ensure that the board can be inserted into the USB connector in either orientation.
The board can also be powered by an external voltage source via the pads marked "+" and "-".
The light sensitivity can be adjusted by mounting one, two, or all three of the included 1 MΩ resistors:
- One resistor: high light sensitivity
- Two resistors: medium sensitivity
- Three resistors: low sensitivity
Specifications:
- Operating voltage: 5-15?VDC
- Current consumption: ~5 mA (at 5 V)
- Dimensions: 25.4 x 38.75 mm
