Series SCR Lamp Flasher Handles A Wide Range of Loads Brief full-power flashes are obtained when the SCR conducts during positive half cycles of the line voltage. The SCR fires when the voltage at the divider, R3 and R4, reaches the gate-firing level. Di ... read more>>
Sequential Led Flasher With Reversible Direction A 555 timer clocks a 74190 up/down counter. The 74190 drives BCD decoder driver 7442. The 7476 is used to reverse the count on 0 and 9, which results in an up-down-up-down count sequence.The Circuit D ... read more>>
Large Lcd Display Buffering Driver Large LCD devices of 1" or more exhibit a large driving capacitance to the driver circuits. To solve this problem, the drive circuit shown (see the figure) introduces a buffer amplifier for each ... read more>>
Flash Signal Alarm This circuit is useful if you need a low-energy flashing alarm. The 200 to 400-dc supply should have enough internal resistance to charge the 0.5 uF capacitor between flashes, about 2 or 3 time consta ... read more>>
Dark-Activated Led Flasher This circuit can be used as a small beacon or marker light, and toys or novelty items. R1 is an LDR that has >= 10 k dark-resistance, or a CDS photocell. C1 determines the flash rate.The Circuit Di ... read more>>
