Circuit

A circuit is a closed path that allows electricity to flow from one point to another. It may include various electrical components, such as transistors, resistors, and capacitors, but the flow is unimpeded by a gap or break in the circuit.

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Microcontroller Battery Monitor Circuit Needs Only One Pin

“This circuit solved a problem encountered in developing a portable device with an ARM Cortex-M0 processor. The power supply consisted of two AA batteries (2 × 1.5 V), and I needed to signal the user about the battery’s state …

Adding ADC to Microcontrollers without ADC

“I recently had the need to carefully measure a voltage with a microcontroller which lacks an analog-to-digital converter (ADC), and I hacked together a quick and dirty method to do just this using a comparator, two transistors, and a few …

Unipolar Motor Controller

Two circuits will be built today to control Unipolar motors. A unipolar motor is a type of step motor described as needing only a current source. By contrast, bipolar motors require two current sources to move. The complexity of this …

DC Motor Controller

Today we will build a circuit to control DC motors. Electric motors of all kinds work thanks to electromagnetism. They convert electric energy into mechanical energy. DC motors are relatively simple control motors. They are motors that have two modes …

Timer with 555

Today we will build a circuit that is a timer. The IC 555 was used. This was set to Mono-stable mode. When the button is pressed the time starts and the LED lights up. After a while it goes off …

Obstacle detector using Infrared

Today we will build a circuit that detects the interruption of an infrared beam allowing an alarm to be created. The LM358 IC has two comparators. Pin 3 which is the non-inverted end of the voltage comparator is connected to …

Infrared LED Alarm

Today we will build a circuit that detects the interruption of an infrared beam allowing an alarm to be created. The LM358 IC has two comparators. Pin 3 which is the non-inverted end of the voltage comparator is connected to …

Shutdown button for Raspberry PI

Today we will build a small circuit that lets you execute commands in Raspberry Pi to do whatever we want when a button is pressed (in our case to start the shutdown process). This circuit is quite simple and requires …

ADC for Raspberry PI

Using an MCP3008 IC we will add the ability to read analog values on a Raspberry Pi. The Raspberry Pi unlike the Arduinos natively has no way of reading analog data. By adding an integrated as the MCP3008 we can …

Signal Meter (VU Meter)

Today a circuit will be built using an LM3915 IC and it will visually represent the intensity of an audio signal. The LM3915 has an amplitude of 30 dB and the 10 LEDs are activated in 3 dB intervals. If …