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    PIC multimeter help

    Hi All I'm working in a project well a simple pic multi-meter based on on bench power supply one I have working ok, Now I want to make  a portable meter of it now this would be ok if you made sure you got the connections the correct way roun, I know I could add reverse polarity diodes but I...
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    0-30V Stabilized Power Supply

    I was able to open it try this one I've zipped it up see how you get on Placa_principal.zip
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    0-30V Stabilized Power Supply

    why do people need to waste time on simulating the design beats me, The PSU works perfectly has it so in my eye why try and reinvent the wheel. I've found from past experience simulating don't always to seem to work like they do in real life. you can't feel the monitor for heat  ;D
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    0-30 Vdc Stabilized Power Supply

    Thanks for the comment,
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    0-30V Stabilized Power Supply

    You could not have set voltage anyway, You could set the voltage with the wiper but you would have no way of limiting it, if you where to move the pot. The only way would be remove pots and use PWM from the pic. The same goes for the current control. You can read real time voltage,current and...
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    0-30V Stabilized Power Supply

    I remember now why I created a new BOM is that some of the parts do not exist now like the .33R power transistors resistors . I will check that all the values are correct and I have decided to leave my version has it is, After all it is so simple to cross reference between the two drawings and...
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    0-30V Stabilized Power Supply

    R17 is R16 on my schematic They are both laid out the same order so you can cross referaence from the original version. If I get time I will correct my version so it's the same has the original
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    0-30V Stabilized Power Supply

    I will look into it and let you know, Your the first one to spot it.
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    0-30V Stabilized Power Supply

    So you have used Audio's schematic ?, Did you redraw the schematic and then transfered the design over to the PCB package then once you laid it out you ran the DRC rule checker ? or Who's PCB layout you used ?, The only reason I ask is if you have just laid out the PCB yourself just from the...
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    0-30V Stabilized Power Supply

    Looking at your PCB the output tracks are still not big enough to take the current for 5A and yes the pads need upgrading. Here is the modified version this will either do the 3A or 5A version, For the 3A just leave out Q3A & R20A For the 5A change R7 must be 0.27 ohms/10W (TB4 or the 2...
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    0-30V Stabilized Power Supply

    Yes it will require a little Mod, I only built the 3A version I've never really as the need for 5A, The mod is esy to do you can just hardwire the third transistor onto the exsisting tracs just solder the emitter resistor straight onto the pin of the transistor. I can mod the pcb to take the thr...
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    0-30V Stabilized Power Supply

    Yeah I did and you can download it from here, It's single sided and it can be 3A or 5A your choice
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    0-30V Stabilized Power Supply

    I never had that problem, Have you checked that the bridge rectifier is correct ? I used one like this from here http://www.rapidonline.com/Electronic-Components/Discrete-Semiconductors/Bridge-Rectifier-Diodes/4A-8A-In-line-bridge-rectifiers/29673 It's like audioguru stated it must have been...
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    0-30V Stabilized Power Supply

    You could do what I did went to the Texas instruments web site and ordered some samples then you get them for free. You need to listen to audioguru the old design has many faults, I have ben there and done that tried everything to get the old design to work but in the end it went in the bin and...
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    0-30V Stabilized Power Supply

    It is sized 1:1 and it does not need to be mirrored. When you go to print it just make sure the the page scaling is set to none, This is how I did mine and it worked perfectly.
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    0-30V Stabilized Power Supply

    Yes a 24V transformer can be used but you will not get the full 30V plus you will suffer a higher ripple at max voltage set to max current, This would be ok if only want 25V PSU Yes you can use 2N3055 instead of TIP3055
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    0-30V Stabilized Power Supply

    This is my version of the PSU , All tested all working no problems complete with PCB and BOM aslo with connection drawing, I mounted the transistors on a seperate PCB but you don't have to use the PCB you can just hard wire them. EL_power_supply.pdf
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    Led display Digital Voltmeter question

    I brought a kit from Velleman which was based om the ICL7107 and I found that this gave unstable readings and could never cure the bouncing of the readings, May be this is why they stopped selling it ? So in the end I decided to design and build my own based on the MAX7219 and PIC16F876, This...
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    0-30V Stabilized Power Supply

    I forgot to add the latest schematic to the PDF file Picmaster Schematic_Prints.pdf
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    0-30V Stabilized Power Supply

    Here is my vesrion of the power supply comlete. PDF file is a new BOM(for this project only),PCB copper side, PCB overlay, assembly drawings Please let me know if you find any errors or suggestions Picmaster
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