A very simple IR remote control switch for an electrical appliance

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This project describes a technique of adding the remote control feature to an electrical appliance. The goal is to construct a black box where you can plug-in your 120V AC appliance (it can be easily modified for 220 V mains supply too) and control the ON and OFF operations with a TV or DVD remote that uses modulated infra-red (IR) pulse train of 38 KHz frequency. I did this project for my wife who studies late at night on her bed and later feels tired to stand up and turns the light off. Now she does it from bed with

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Using Fixed Voltage Reference (FVR) for A/D conversion in enhanced mid-range PIC microcontrollers

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The reference voltage plays a very important role in any A/D conversion. It determines both the range and the resolution (Volt/Count) of the A/D conversion. Besides, the accuracy of the conversion also depends upon how stable the reference voltage is. Usually in PIC microcontrollers, the reference voltage for A/D conversion can be selected as the supply voltage itself or provided externally through one or more I/O pins. But the new enhanced mid-range family of 8-bit PIC microcontrollers have a built-in module that generates a stable reference voltage internally. It is called Fixed Voltage Reference (FVR) where the output is very

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UNI-DS6 development board for experimenting with dsPIC30F6014A

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UNI-DS6 is an universal development board from mikroElektronika for experimenting with a wide range of microcontrollers including PIC, AVR, dsPIC, ARM, and 8051. I am going to use this board to educate myself about Microchip’s dsPIC Digital Signal Controllers (DSCs). The dsPIC DSCs are 16-bit high performance microcontrollers and more powerful than regular PIC devices. They are special because they combine the best features of microcontrollers with the computational capabilities of a Digital Signal Processor (DSP), and they are capable of doing complex mathematical operations involving Fourier transforms. I am going to describe briefly about the features of UNI-DS6 board

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LM386 based stereo audio amplifier with digital volume control

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Due to its simplicity (requires minimum external components) and high availability, LM386 is very popular among hobbyists for use in low-voltage audio amplification applications. Most of the time a potentiometer is used at the input side of LM386 to provide a volume control in the output speaker. The potentiometer does not control the gain of the amplifier itself, but it creates a voltage divider network at the input, which in fact controls the fraction of the audio signal that is fed to the amplifier. This project is about a stereo audio amplifier using two LM386 ICs with digital volume control for both

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How to interface MAXIM’s DS1868 digital potentiometer with a PIC microcontroller

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Potentiometers find applications in many electrical devices. For example, a light dimmer uses a potentiometer to control the brightness of lamps. In amplifiers, they are used to control the output volume of the music, or change the bass level. In an adjustable power supply we see potentiometers to vary the output voltage and current. In a frequency generator, they are used to control the duty cycle and frequency of the output signal. These potentiometers are electro-mechanical transducers that convert the rotary or linear displacement into a change in resistance. This change in resistance can be used to control anything from

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