A time controlled switch is an automatic timer switch that turns an appliance ‘on’ for the desired time duration. After the preset time duration, the timer automatically switches off, disconnecting the appliance from the power supply. The time duration for which the appliance should be ‘on’ can be set from 1 to 99 minutes. This switch obviates the need to continuously monitor the appliance—an advantage over ...

Description Create a design and simulate using EE-Sim: [MAX15058] The MAX15058 high-efficiency, current-mode, synchronous step-down switching regulator with integrated power switches delivers up to 3A of output current. The device operates from 2.7V to 5.5V and provides an output voltage from 0.6V up to 94% of the input voltage, making the device ideal for distributed power systems, portable devices, and pr ...

I was thinking about making a resistor decade box, but I found the rotary switches that are used in these most of the time rather expensive and a bit old fashioned. That's why I decided to use a rotary encoder and select the resistors with a microcontroller. Now I only had to find a way to "make" the resistance. Switching resistors with transistors or mosfets gives a high switch resistance and can't handle ...

UPDATE: I eventually decided to use a single switching regulator that I found on digikey which is both awesome and well priced. See this blog post update about it. My first DoorBell Mote prototype was working nicely and it allowed monitoring the door bell (while also triggering it remotely – toddlers love it). But I wanted more. On weekends the family likes to get a well deserved nap during the day and ofte ...

Modern DC/DC controllers from company Infineon, like TLF51801ELV manage even big challenges. Perhaps everyone knows, that modern switch-mode power supplies are able to efficiently convert voltage and to replace linear power supplies. Features of ready-made DC/DC modules as well as SMPS controllers themselves are still better and nowadays it´s no problem to construct a 10A power supply on a small area. It is ...

Here is a simple PIC16F84A alarm clock. This page summarizes this discussion (in french) in my forum, where Samir (aka numerique1) requested for help to build a weekly alarm clock for his school. Many thanks to him for his tests and patience. This clock counts seconds, minutes, hours and day of the week. Time is displayed on 4 seven segment LED displays, and is adjustable with three buttons at start time (u ...

RS232 EIA232F TTL and USB Adaptor Examples Tx and Rx Baud Rate, Misc Asynchronous Tx Loop-Back Test $50 Robot UART What is the UART? The UART, or Universal Asynchronous Receiver / Transmitter, is a feature of your microcontroller useful for communicating serial data (text, numbers, etc.) to your PC. The device changes incoming parallel information (within the microcontroller/PC) to serial data which can be ...

Build a low-cost and very simple serial programmer for a PIC16F84 Microchip Flash Microcontroller. Below picture is my personal writer for F84 chip, it works very nice with Nigel WPicProg V1.20. Introduction I finally found a very nice universal window based software designed to work with any serial programmers for PIC16F84, i.e., WPicProg16 V1.20, written by Nigel Goodwin. Build this programmer before star ...

Description The ISL9307 is an integrated mini Power Management IC (mini-PMIC) ideal for applications for powering low-voltage microprocessor or multiple voltage rails with a battery as an input source, such as a single Li-ion or Li-polymer. ISL9307 integrates two high-efficiency, 3MHz, synchronous step-down converters (DCD1 and DCD2) and two low-input, low-dropout linear regulators (LDO1 and LDO2). The 3MHz ...

Introducing... the Energy Wristband A wristband that tells you energy changes in your home. It connects via a Raspberry Pi computer to a base station like a'current cost' or similar. When a change in energy usage occurs, the wristband vibrates and a small LED bargraph shows your current usage from 1 to 4. Realtime energy use can be queried by pressing the button.     Temporary ownership = maximum ...