White LED on 1.5 v Supply

In this post you will find circuit on how we can light up white LED on 1.5 v supply. Heart of the circuit is the transformer winded on 2.5mm by 0.5 mm core using 0.095 mm wire.

2 White LED on 1.5 v Supply

The circuit below uses only 1.5v to light up 2 white LED.

white-led-on-1-5-v-supply
 Components required:
  • T1 – BC338
  • R1 – 2.7 K
  • C1 – 10 n
  • D1,D2 – Super bright LED
  • Transformer – 60 T, 40 T
  • S1 – On/off Switch
  • Battery 1.5 V

White LED Flasher

Below circuit uses only 1.5v to flash a white LED.

white-led-flasher
Components required
  • T1 – BC338
  • T2 – 2N2222
  • R1 – 2.7 K
  • R2 – 47 R
  • R3 – 330 R – 1K
  • C1 – 10 n
  • C2 – 100
  • D2 – 1N4148
  • Battery 1.5 v

For more post on LED click here.

USB Reading Lamp

USB reading lamp is powered using USB port. The USB port provide 5 v and 100mA which is sufficient for this circuit. Cut the one end of the USB cable and use RED(pin1) and Black(pin4) for 5v positive and negative respectively.

 

USB lamp
Parts
  1. c1,c2 – 100 mF 25 v
  2. Zener diode – 4.7v 400m
  3. R1- 220 r
  4. R2- 100 r
  5. T1 – SL100
  6. White LED – 5 nos.
  7. USB Cable