This handheld electric PCB drill speed controller is cheap, easy to build, and only uses a few components. Basically, it is an Arduino Uno based PWM controller that operates at a relatively high frequency (Figure 1). It features almost 0-100% DC ...
This expandable LED display for a microcontroller in Figure 1 has a simple interface with only 6 data/control wires and can be easily accommodated to a DIY design. The display has static indication. Figure 1. The expandable LED display for a ...
If you need to quickly and inexpensively convert a binary number into a proportional analog voltage, one cool (and easily remoted) way to do it is: 1. Serialize the number into a bit stream with the LSB output first, 2. input the resulting stream ...
Adding a manual reset to a design usually involves designing in a new part with a manual-reset input. But, by adding a couple of low-value resistors, a standard three-pin-reset supervisor can work in most applications. The circuit in Figure 1 ...
It is sometimes necessary for a microcontroller to generate a pulse whose voltage is higher than the power-supply voltage of the microcontroller. The circuit in Figure 1 allows you to generate 14 V pulses from a 5 V power supply. An adaptation of ...
Piezoelectric buzzers find wide use as audible-signal generators because of their low power consumption and clear, penetrating sound. An external driver or a self-driven circuit that oscillates at the resonant frequency of the piezoelectric element ...
Targeted for the smart home, this design leverages two PIC MCUs that use a wireless RF transmitter/receiver to control up to six relays and monitor two analog signals. In this design idea, you will learn how to interface two PIC microcontrollers ...
This 8051 microcontroller-based control circuit adjusts the speed of a small permanent-magnet dc motor via photosensors (Figure 1). The circuit can find applications in light-tracking systems for adjusting tracking-motor speed depending on the ...
This article describes a portable breadboard-friendly adjustable power supply, designed as an ideal supply for Arduino projects and other low-power circuits. It is capable of providing from 0 V to 5.5 V at up to 0.5 A, and is powered by two ...
A recent Design Idea prompted me to offer the simpler solution that I used in a recent project (Reference 1). We needed a momentary power switch with processor supervision. This supervision would allow the processor to delay a power-down request ...