Bicycle back Safety Lights


Posted on Feb 7, 2014

This circuit has been designed to provide a clearly visible light, formed by 13 high efficiency flashing LEDs arranged in a pseudo-rotating order. Due to low voltage, low drain battery operation and small size, the device is suitable for mounting on bicycles as a back light, or to put on by jogger/walkers. IC1 is a CMos version of the 555 IC wired


Bicycle back Safety Lights
Click here to download the full size of the above Circuit.

as an astable multivibrator generating a 50% duty-cycle square wave at approx. 4Hz frequency. At 3V supply, 555 output (pin 3) sinking current operation is far better than sourcing, then LED D1-D6 are connected to positive supply. In order to obtain an alternate flashing operation, a second 555 IC is provided, acting as a trigger plus inverter and driving LEDs D7-D12. D13 is permanently on. The LEDs are arranged in a two series display as shown below, with a center LED permanently on. This arrangement and the alternate flashing of the two series of LEDs provide a pseudo-rotating appearance.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Video DVM circuit
    Overvoltage protection for logic
    Simple 2M 6M Transverter Circuit
    Video Isolator
    Simple TV Remote Control Jammer
    Diesel and Horn Circuit for Train
    reader cloner
    49MHz Toy RF Transmitter
    One-IC two-tones Siren
    Open Loop Speed Control of a DC Motor via 8255 Controller
    Free Energy Schematic
    Amplifier circuit equivalent
    Watermelon raw and cooked discriminating circuit



    Top