Instructables

Usb lamp with dark sensor

Step 1: Parts list

12 x   bright white leds 1200 
1    x  2N3904
1    x 100 r resistor
1    x  10k resistor
1    x  usb cable 
1    x 10 r 1/2 watt resistor
1    x LDR

Step 2: Circuit diagram

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complete the circuit according to the circuit diagram, connect the led in parallel (you can add more led if you need) also check fr the polarity of the led before placing it on the board because re-soldering makes the circuit messy

Step 3: Step 2

Step 4: Conclusion

 hope you like the circuit......