A Button and four LED Lights
Need a design – Simple one button push button to turn on 4 different LED (3mm Dome) every time you press the button. JE USA […]
LED-Circuits
Electronic Fifteen LED Roulette
The following was submitted on July 11th, 2007. Message: I want to combine Ne555 with 74154 IC.The indication of the outputs must be shown with […]
Millivolt Meter using a LM3914 LED Dot Display
Here is a easy to read ‘Analog’ Millivoltmeter. Just like the Moving Coil Voltmeter, but does not have that resolution. This gives a easy indication […]
Resistance Measurement Analog LED Meter
This is a LED Analog Meter, This can be used as a Resistance Meter and Low Impedance Voltmeter for Battery Levels. To measure battery voltage, […]
LM555 Voltage Doubler
This circuit shows the voltage doubler working with a 555. LM555 has good drive 200mA, both Vcc and Gnd. 555 has the advantage of having […]
FET Current Source and MOSFET
This is a constant current source using a FET. This is the most simple replacement to series resistor to limit current. The N-Channel FET BF256C […]
Audio Visual User Interface with Ack
This circuit is an User Interface part of a Security Alertness Monitor that i designed decades ago. The circuits are here – Digital Circuits – Part 1 The RAM […]
InfraRed Detector for Proximity Switch
The proximity switch can work for a wide range of power, from 8v to 18v DC, D3 protects reverse power supply connections, and U1 regulates […]