USB Powered LED Night Lamp Circuit

These days, we can see various USB gadgets on the market. today we try to make USB powered LED night Lamp. You can use it 
as a table lamp by connecting to PC or Laptop. This circuit operates using USB port as its power source. D1 indicates connection 
with USB port. The computer USB port able to provide up to 500mA current. But here, we use 100mA current for this circuit, 
because it's very safely to your computer.You must be confirm accurately the pins (Positive and Ground leads) of USB port.

Components:

S1 – Switch (Can be use to turn ON/OFF lamp)

R1, R2 – 560O/0.25W

R3 – 1K/0.25W

D1 – Red mini LED

D2 – 1N4007

D3...D8 – 6 x 8mm White LEDs

C1 – 0.01f (103) Ceramic

Q1 – BC547 or BC548

Please Note:

You must be confirm accurately the positive & ground leads of USB port before build the circuit. 

Check again the positive & ground leads of USB port before connect it with PC. 

Don't short circuit.