Simplified white-LED flasher


Posted on Aug 14, 2012

The white-LED flasher in Figure 1 offers an alternative approach to a previously published idea (Reference 1). Targeting use in portable appliances and products powered by a single cell, this circuit flashes an LED to provide a highly visible warning signalfor example, to indicate power on, battery low, or another eye-catching visual signal. However, white LEDs typically present a forward-voltage drop of 3 to 5V. Given that a single cell`s end-of-life output voltage decreases to 1V, flashing a white LED from such a low voltage demands special circuit techniques. The circuit in Figure 1 exploits the low-voltage capabilities of Fairchild`s universally configurable two-input NC7SV57 logic gate. The NC7SV57 operates from a supply voltage as low as 0.9V, a key requirement for single-cell applications.






Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    4 switch combination Combination Lock
    Low-voltage-wien-bridge-oscillator
    Audio Mini FM Receiver
    Recording Level Meter Circuit
    light sensor circuit using pic16c63
    lm3914 ic based on simple battery tester
    Remote Control Tester Circuit PCB
    USB Powered Mobile Phone Battery Charger
    TTL NAND and AND gates
    DEMODULATOR circuit
    Wien-Bridge Oscillator
    Audio Noise Generator Schematic
    Micro Power Transmitting Station
    RING COUNTER WITH VISUAL READOUT



    Top