Saturday, July 20th, 2024

## Very simple charge pump voltage inverter

It is sometimes necessary to use a negative voltage in a construction that already has a positive drive voltage. For example, you might want a symmetrical drive voltage for an op-amp that otherwise only consists of logic circuits. Making a circuit that inverts the drive voltage can be a problem, especially in a battery derived equipment. In this circuit, T1 …

## Water heating calculator

This water heating calculator can help you determine both the amount of heat required to raise the temperature of some water (H2O) and the time it will take. It considers the heat capacities of all three states of matter, so it also works if you want to melt the ice or boil water or heat steam. This calculator uses the …

## Simple voltage doubler

This circuit produces a dc voltage at the output that is almost twice the input voltage. For a 12V input the output is 22.1V @ 20mA. The voltage doubler is based on the charge-pump principle of operation. A charge pump is a kind of DC-to-DC converter that uses capacitors for energetic charge storage to raise or lower voltage. Charge-pump circuits …

## Check out the e-books from Element14!

The element14 community provides support and inspiration through a combination of articles, design challenges, roadtests and the power of close to half a million global members with their combined experienced and knowledge. They have released a series of e-books which brings together hints and tips from the element14 community team, inspiration for makers looking to get started, or for inspiration with a project.

## DS18B20 issues

PROBLEM DESCRIPTION I’m using the DS18S20 and DS18B20 in a energy control system. The 1-wire temperature sensors is connected on the same 1-wire bus. Just these two sensors are connected to the bus. The 1-wire is connected to a microcontroller i/o port. To pull down the 1-wire bus, an open drain pulldown transistor and a 1k resistor to +5V are …

## LED series resistor calculator

In electronics, an LED circuit or LED driver is an electrical circuit used to power a light-emitting diode (LED). The circuit must provide sufficient current to light the LED at the required brightness, but must limit the current to prevent damaging the LED. The voltage drop across an LED is approximately constant over a wide range of operating current; therefore, …

## Temperature logger running on Raspberry Pi

In this tutorial, we will implement a simple temperature logger on the Raspberry Pi 3 and connect four DS18B20 temperature sensors to it. The temperature measurements will be stored in a database along with a time stamp. We have selected InfluxDB as the database engine as this is a time-series database and integrates very easy to Grafana. Grafana will retrieve …

## Testing the MH-Z19 Infrared CO2 Sensor Module

A short review of the MH-Z19 CO2 sensor from Winsen connected to the UART of Raspberry Pi 3.