The input circuit is a simple keypad matrix. To read each button push, the Arduino brings one keypad input line high and checks the voltage of the four output lines in order. The diodes on the PC ...

16-button keypads have a clever method of encoding ... The trio’s solution is an elegant adventure into circuit design. With two diodes and a voltage divider, they devise a simple circuit ...

Looking for a simple circuit to control the light intensity of Light Emitting Diodes (LEDs) or similar lighting ... the schematic diagram to complete the construction, and use any standard 9VDC ...