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Showing posts with the label 4066

Centralize power switch for PC arrays with power failure monitor

UPS system is a common peripheral in computer field. Now most of these UPSs are equipped with USB driven system shutdown software. But some of the cheap UPS system may not have software controlled PC shutdown systems and some of them had some limitations too (for example operating system compatibility issues, supporting for multiple nodes, etc.). In this post we design power failure monitor with centralize power switch for array of PCs. Using this system administrators can turn on multiple PCs with single button press and all of these PCs get power down automatically at power failure. To reduce cross platform issues we design this interface to work with main-board power switch and because of this administrators may not need any special software for this system. Most important point of this system is its independence with UPS hardware. Prototype of centralize power switch project Main controller of this system is PIC10F200 - 8bit microcontroller. Thanks to its SOT-23 package w...

Smart Audio Box

Smart Audio Box (SAB) is microprocessor controlled audio switch and amplifier system, which is specifically design for audio composers and for audio engineers. SAB consist of 4 high impedance stereo inputs and two output modes. One output mode can drive stereo headphone/earphone and other output mode can drive pair of 8W speakers. In prototyping stages we identify those modes as " Personal Mode " (headphone output) and " Audience Mode " (power amplifier output). Another main feature of this system is its programmable 16 step attenuation controller. This attenuation controller helps to control the audio output level of each output-mode. Prototyping version of Smart Audio Box The main component of SAB system is ATmega8 MCU, other than that headphone amplifier is design around NJM4556 high current operational amplifier and power amplifier is based on TDA1521A. To operate, this system requires 2 power sources. Microcontroller, ADC interfaces and CMOS logic-s...