what is meant by programmable digital power supply using 8051 microcontroller?
341482
Ok break it down:\n1) A power supply converts AC power (110 in the states) to some other required voltage. For this (lab) project I'd presume a DC regulated voltage from, say 1.5 to 15V something like that.\n\n2) Digital and programmable means you'd control the output voltage with some sort of digital signal like up/down buttons, a keypad, or a PC hookup.\n\n3) You are supposed to use an 8051 to accomplish this.\n\nSo there are several ways to do this. One way would be to have the 8051 accept a command to set the voltage and produce a PWM signal. Let's say the PWM signal is a 5V output switched from 0 to 100%. You can use an RC filter to produce 0V to 5V from this signal. If your instructor is nice, you could argue that this meets the criteria -- especially if you use it to drive a pass transistor to develop some serious current (but your voltage is now 0V to 4.3V because of the BE drop).\n\nBut I'd instead use an op amp with gain X3 (plus a little extra) so that I got from 0 to 15.7V and then use the pass transistor. Another idea would be to use the voltage to drive a simple current source which would program a LM317 voltage regulator.\n\nWeb searches on things like LM317, PWM, and "pass transistor" are your friends here.
710844
‘softwired’ (using a programmed microcontroller) or hardwired (using traditional electronic components).
970234
try AC BELL / Thermal Take.\n\nAC BELL's a Power Supply brand specialist for Branded / Home Made CPU, such as MAC, Fujitsu, HP, etc. But I Forgot the exact URL.\n\nBut for thermal take, try this
387324
If its a 12v power supply you need then i think Radio shack should have a suiteable replacement  and they have power supplies with changeable polarity. Ebay has them but a lot of looking to find one .
247015
I heard that at least once upon a time you could only get Dell power supplies that work with Dell Computers. I know this was definitely true for Compaq. If you got the replacement part from Dell it would most likely cost a fortune. Open the case and find out the wattage. Is the case a Micro ATX, or an ATX (Basically itty bitty case or big case) Is the power supply up near the top like "normal" computers or weird and sideways.\nI would saya if the power supply is 250 watts or more and is in a standard computer spot it probably is a standard ATX power supply. you can look on Newegg.com for a bunch.
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Nothing is for free.  Peripherals you put inside your computer take certain amount of power.   Motherboard, keyboard, mouse, graphics card, hard drive, cd drive, and etc. etc. all require certain amount of power.\n\nThe issue with have a good power supply isn't about speed.  It's about stability.  Your power supply is in charge of converting the AC current from the wall to DC.  An ideal power supply will provide stable DC current with very little ripple current.   Ripple current is the deviating fluctuation that is present in all DC current provided by a power supply.\n\nAnd it is possible to have too much wattage but only in extreme cases.  Electronic device like power supplies work with tolerance levels usually given in percentages.  So two different rated power supplies built with 5% tolerance will have different tolerances.  With a lot of power you lose a precision.  With precision you use a certain amount of power.  (Analogy would be fidelity and power in audio terms.)
425700
Try a book called "C and the 8051". Writing code for the 8051 is basically the same as any other processor, so if you know C, you have little else to learn. Mainly, you want to know how the processor works (RAM layout, bits and bytes, interrupts, and any special hardware). Keil is probably the best compiler out there for the 8051, so have that too.\n\nP.S. Normally all programs are done in C. C++ really isnt needed for the 8051.\n\nGood luck!!
1016840
Use a 7106 or 7107 IC.  They provide analog to digital conversion and drivers for a liquid crystal display.  The source in "references" provides kits to make a panel mounted ohm or volt meter using these ICs.  \n\n"Google" these ICs and you will find more.
575580
http://www.pcguide.com/care/care/gen/powerOnOff-c.html
620372
there are micro chips you can get that you can use to make a ide 2 usb cable but then you still have to build a power supply for 12 and 5 volt supply and you would be better off getting the ide 2 usb then trying to do micro circuits and then the static and making the circuit board basically you almost need to go to devry or MIT to learn how to do it so make it easy on yourself and buy it
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http://www.digchip.com/datasheets/parts/datasheet/280/MAX4603.php\n\nFour switches, two NC and two NO. Used in Relay Replacement, Test Equipment, Communication Systems, PBX, PABX Systems, Audio-Signal Routing. \n\nthe complete datasheet can be found on maxim-ic site:
1005090
Something that adds numbers using digital logic. It's works by connecting the carrys from four full adders to create a 4 bit ripple adder. The carry ripples down the adders, which is why it's called a ripple adder.\n\nGenerally considered a slow design. Look into Carry Look Ahead adders if you want something faster.
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If it's for a simple hobbyist application they need to know only the resistance value and its power rating.\n\nA full specification would also include:\n\ntolerance,  thermal coefficient,  maximum voltage.
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IEEE 829 - Test Procedure Specification (TPS)\n\n\n...did you SEE the memo about the new cover sheet?
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Do you mean power supply or cable?\n\nI need more info
186229
Here are some sites that may help.  Both have circuit examples utilizing LVDT's.  Hope this helps.
13376
I believe you can 'short' thru a couple of pins and the PSU will operate but I don't know which ones.\n\nI can tell you to check out pimprig.com. They are a computer modding website and I'm sure the question has been answered there recently.