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  1. Hi all, Finally after some months have gone by, my build of the Power Supply is done. I have used liquibyte schematic Rev. 8 and had made the cirquit board according to the Gerber.zip file he posted here: 0-30V Stabilized Power Supply Page 88 posted October 6, 2014 "http://electronics-lab.com/community/index.php?/topic/29563-0-30v-stabilized-power-supply/&page=88" I left out D10 and R15 as per his description. I have plenty of boards leftover if someone has a need for it. There was only one mistake liquibyte made which have outlined in one of the pictures uploaded here. I was fortunate enough to get a big case with a Toroidal transformer from the scrapyard. Also many parts are recycled from various sources. Regards, William
    4 points
  2. Guest

    0-30V 0-3A Latest Data

    Finally, my post with the Eagle .sch and .brd, full gerbers, and parts list for Digikey in a zip file. I'm also including many of the pics I took as I was building that were posted both before and after this post. I'm still not completely done and may add more pics later. One thing I have changed is the third transformer for the auxiliary circuitry for the temperature sensor and fans and the displays (I wanted a better transformer than the Radio Shack special I had on hand). Archive attached. 30V.zip
    3 points
  3. An H-Bridge (Full-Bridge) driver is quite popular in driving loads such as brushed DC motors and it is widely used in robotics and industry. The main advantages of using an H-Bridge driver are: high efficiency, rotation direction change, and braking the motor. In this article/video, I have introduced a complete H-Bridge DC motor driver using four IR3205 power MOSFETs and two IR2104 MOSFET drivers. Theoretically, the above-mentioned MOSFET can handle currents up to 80A, however, in practice we can expect to get currents up to 40A if the MOSFET temperature is kept as low as possible, using a big heatsink or even a fan. References Article: https://www.pcbway.com/blog/technology/Powerful_H_Bridge_DC_Motor_Driver.html [1]: IRF3205 Datasheet: http://www.irf.com/product-info/datasheets/data/irf3205.pdf [2]: IR2104 Datasheet: https://www.infineon.com/dgdl/Infineon-IR2104-DS-v01_00-EN.pdf?fileId=5546d462533600a4015355c7c1c31671 [3]: 1N5819 Datasheet: https://www.diodes.com/assets/Datasheets/ds23001.pdf [4]: IR2104 Schematic Symbol, PCB Footprint, 3D Model: https://componentsearchengine.com/part-view/IR2104PBF/Infineon [5]: IRF3205 Schematic Symbol, PCB Footprint, 3D Model: https://componentsearchengine.com/part-view/IRF3205ZPBF/Infineon [6]: CAD Plugins: https://www.samacsys.com/library-loader-help
    2 points
  4. Thanks for sharing your project with us. Could you give more details on the control board?
    2 points
  5. The original circuit should work fine up to 15V at 1A if you replace the old opamps with the newer higher voltage ones. You probably should recalculate the resistors that set the maximum voltage and current outputs. If the Chinese kit uses the transistor that shorts the opamp output when the power is turned off then the resistors that feed the transistor need to be recalculated for the reduced voltage. I have used perforated stripboard for many projects including very complicated ones. The copper strips are cut to length with a drill-bit and become almost half the wiring of a pcb. The parts and a few short jumper wires become the remainder of the wiring. Only one wire is in each hole so changing a part is easy like on a pcb.
    2 points
  6. Hi, as promised I made an English translation of my working. Maybe there is few mistakes and I am sorry for that ! Good reading. ExplicationEN.pdf
    2 points
  7. So Finally which version of schematic is correct / flawless to build the PSU ?
    2 points
  8. February 23 above on this page has the latest schematic of the revised 3A lab power supply.
    2 points
  9. Does anyone has LM3914 pspice library? i desperately need it..pleeeeease!
    2 points
  10. Guest

    Low power solenoid?

    I want to apply force for an extended amount of time (10 secs to a couple minutes) using a solenoid actuator. Unfortunately, it seems that solenoids use a lot of power when they are active. Is there a solenoid type that will only use power when switching between active and not active? There's probably a way I can do this with an external mechanism, but I was wondering if there may be commercial solenoids that have this built-in. Thanks, Jessica
    2 points
  11. Illegal content (ebook/magazines/software) will be deleted without any notice. Thanks
    2 points
  12. In a few circuit diagrams i have they refer to a what seems to me is a transistor with B C E as a overload protector and with number A16 and i have looked for a few hours on the net and i can't find anything on this little fellow, Anyone knows what I'm looking for and wanna share that info Please .... Come on !! 48 visits !! some one must know what it is !!! PNP is it also...........
    2 points
  13. At last i got a theori from a totally different place and he wasn't shure either but he had a weak memory that it could be 1A16 and a PNP transistor but after several deep searches on the I-net it didn't make any kind of senses whatsoever ???
    2 points
  14. When you use your resistive divider to drop the voltage down to 5 volts, you just need to select values of resistors to limit the current. This is basic ohm's law. V/R. Was this your question or did I misunderstand? I am not sure how you intend to monitor status by using one 5 volt pin. As an interface to the parallel port, you could use an LM3914. This would give you the resolution you need. There are also many other ways to proceed. You need to convert from analog to digital to read anything useful from the parallel port. MP
    2 points
  15. Hi TJBraza, http://www.analog.com/UploadedFiles/Data_Sheets/ADT7485A.pdf Although, it will probably require a small program written in C or Visual basic to convert the string MSB & LSB into a more easier read etc... Take a moment and review the data sheet, the IC has a lot of potential.
    2 points
  16. I can't find SL100 & SK100 transistor :'( Which transistors can replace these? Thank you for your help~ ;)
    2 points
  17. Calm down people. It is not Mixos's fault, if it is against the law he has to remove the content. This site is very good for asking electronic related questions, I have yet to find a better one.
    2 points
  18. 1 point
  19. You will have to open the Eagle schematic with the software and then you will see that the values are linked to the reference number of the parts. This way it will be easy to identify.
    1 point
  20. If the transformer is rated at 24VAC/2A then it provides a maximum power of 24V x 2A= 48VA. But if the output is 30V at 2.0A then the load uses 30V x 2A= 60VA plus heating power. The peak of 24VAC is 40V which feeds the bridge rectifier which charges the main filter capacitor to the peak voltage minus the rectifier forward voltage. So then the transformer must produce 40V at 2.0A= 80VA which is much more than the overloaded 48VA. 80VA/24V= 3.33A, not 2A. For a regulated output of 30.0VDC at 3A then I recommended using a transformer rated at 28VAC/4.3A. For an output current of 3A then you must look at how much heat is produced by the single output transistor which is why I recommended using two output transistors to share the heat. Edited with strike-throughs.
    1 point
  21. 1 point
  22. Hi there. I need a good bench power supply, which i want to build myself, for my hobby lab. The thing is, i have been thinking about LM-317 as my linear voltage regulator (and because here where i live i don't have no access to better ones). The design must have these features: a)Current control from few mA to 5A b)Voltage control from 0V to 30V. For this purpose I've built this schematic, which i attached here. Please, tell me what you think about this project or if does work or does not, for i am a beginner in these things. R8 is just a dummy load. The things i need help: 1) How can i add a minimum load (10 mA as by LM-317 datasheet) to keep the power supply operating in different potentials? 2) I need a replacement for 2n3822, i can't find it in my country too. 3) Can I run it from a fixed switched power supply (way more cheaper than buying a transformer here)? 4) In the future, I'm thinking about adding digital control with PWM to this circuit with Arduino or something like that. Do you think this is feasible? Thanks in advance and sorry for my English. PS: i have already looked here in this forum about the 0-30v power supply with op amps, but i really like the LM-317 concept, although i will build this last one if my project fails.
    1 point
  23. Hi, I just finish my power supply ! I made a PDF document (with a lot of picture and explanation) who resume all the story about this adventure, and made a lot of measurment ! It is in French but I will translate in English soon. I thank all this community, who made a great job ! I join you some photos and my work on a PDF format. Alimentation0_30V.pdf
    1 point
  24. Thanks for sharing this project. I just edited it a bit, so code would look better.
    1 point
  25. Since it was years ago I do not remember which page of which thread has version 6 or 7. I have the schematic and parts list of version 6 here:
    1 point
  26. Dmitry

    MS.NET on ARM devices

    Some developers really need MS .NET Framework for some reason on their ARM devices (mainly on Raspberry Pi). So, basing on their requests, I have made a short tutorial on how to setup .NET on Raspberry Pi.
    1 point
  27. HarryA

    Transformer Watts

    I enlarged the image off the Amazon.com but could not read it https://www.amazon.com/Black-Decker-LCS1620-Lithium-battery/dp/B01M6TQPY2/ref=sr_1_3/141-0275392-4037060?ie=UTF8&qid=1499813460&sr=8-3&keywords=Black+%26+Decker+LCS1620 ...but ebay.com has a readable image http://www.ebay.com/itm/Black-Decker-LCS1620-20v-20-Volt-Lithum-Ion-Battery-Charger-NEW-/272090041874?epid=1640405275&hash=item3f59d48e12:g:mf8AAOSwawpXr3eh 120v @60hz 300ma
    1 point
  28. The clipping circuit does not have energy storage elements like capacitors but it includes both resistors and transistors. This circuit is normally used for the selection in the transmission purpose. The ability of diodes to allow the flow of current in only one direction. A diode is best tested by measuring the voltage drop across the diode when it is forward-biased. A forward-biased diode acts as a closed switch, permitting current to flow. No voltage exists at the diode but voltage may be present in the circuit due to charged capacitors.
    1 point
  29. youth

    PCB manufactureres

    I use WellPCB quite a bit. They aren't the cheapest, but the quality is superb, they may offer features and service you might need. http://www.wellpcb.com/ If it's only a single board or two I tend to make them myself.
    1 point
  30. Ok, skip the voltage and current LCD panel With R18 = 33 kOhm I have got 4,7 A on out... U3 was replaced for another .
    1 point
  31. I have some questions I was hoping someone would help me work through. I am building an outdoor fountain that I want powered by a solar cell. Can I run the solar cell wires directly into the BLDC motor and have it operate only when sun is shining? The brighter the sun the faster the motor turns. Or do I need more circuitry to make it work? If I do hook up a small 3.7 v 2000 mAh Li Ion battery, I need a charge controller? And what? Pump Voltage VDC - 6.0 Nominal Current Draw: 0.27 Amps Power Usage: 7.0 Watts Solar cell Output Voltage: 0.5 volts (Vmax) Output Current: 3.5 Amps (Imax) Average Power: 1.75 Watts Is there any way to turn the motor on for 1 minute every hour on the hour? Miniature controller or driver of some sort? System as compact and concealable as possible. Any help out there For this one? Oh one more thing, is there a micro charge controller out there that would protect the battery when it was full by dumping the load into some LED’s or something of that nature?
    1 point
  32. PCB Manufacturer uses: Front-end tool data preparation, Preparing the photo tools, Print inner layers, Etch inner layers, Register punch and Automatic Optical Inspection (AOI), Lay-up and bond, Drilling the PCB, Electroless copper deposition, Image the outer layers, Plating, Apply solder mask, Silk-screen and cure.
    1 point
  33. audioguru

    Power supply

    You forgot to say if the 10V output from your power supply must be AC or DC. You also forgot to say if the input is AC or DC and its voltage and frequency. Did you know that the output power from your power supply will be 10V x 1000A= 10000 Watts? Where will it come from? What will it be used for?
    1 point
  34. I have a 12v transformer for interior lights and a few lights for it, but want to make it a dimmer light. the working amps are 250mA. I would like to know how to wire up these three ways, so i can try each one and see if its any good and use the best.... Touch lamp. touch the metal to turn on dimmest. press again for brighter and again for brighter and again for off. Manual pot adjuster. and digital potentimeter. press up to turn up and make brighter and down for darker / off, and a reset button to turn instant off. Any help and sche... will be helpfull. Thanks in advance
    1 point
  35. You points are well made; thanks. On day one I found two voltage boosters on Ebay that gave more than 100 volts so I ordered both of them from China. The first one I received was a 12v dc to 200 v dc. After connecting it up and adjusting it for 200 v I put a 100k resistor across the output and got 2 volts output! It took a one mega-ohm load to keep 200 v. The second one (12v dc to 220 v ac) works well. I connected it to the 220v to 120v step down transformer and into a full wave bridge rectifier with a 100mfd capacitor and got 140 v dc; 9.6 volts input. With a 8.4 v NiMH rechargeable battery I get 128 v dc. So I am happy with that and very surprised that the 50/60 hertz transformer works at all!
    1 point
  36. hi... welcome to the forum site. best electronic means that it will show the good features. good means working skills and new features because it explains product quality. I like [url=http://thefarmerworld.tk/agriculturetools.html] modern farming [/url] features. ..............................................................................................................................
    1 point
  37. Looking for an Ultrasonic Cleaner schematic. Gokar
    1 point
  38. How many digital IO lines do you have on your microcontroller? and how many LEDs do you want to drive?
    1 point
  39. A schematic would help us to answer the question. I wouldn't recommend either. A MOSFET would probably be better.
    1 point
  40. audioguru

    Desperate Help Needed

    Nobody makes an LA4058. You got the numbers mixed up, the schematic shows a Sanyo LA4508. Your 13.6V transformer must feed the rectifiers on the Power Part of the schematic. Maybe you fed the transformer wrongly to the amplifier instead of to the rectifiers? Then probably many parts are destroyed. Your 13.6V transformer will produce a peak of 19.2V and the rectifiers reduce it to +17.2V. With a 17V supply the LA4508 produces about 6W at clipping into 4 ohms per channel. Who told you 100W? It has fairly high distortion at low and high frequencies and it cuts frequencies above only 5kHz. Your amplifier probably uses one LA4508 for left woofer and left tweeter and the second LA4508 is probably used for right woofer and right tweeter.
    1 point
  41. 1 point
  42. Guest

    0-30V 0-3A Latest Data

    Continued
    1 point
  43. i need to create voltaic sparks that jumps from one electrode to another between a medium of air. sort of like jacob's ladder. the distance of one electrode to another is about 0.5". i gather that the breakdown voltage of air for said distance is about 4kV. i'm targeting more of around 20-30kV, just to be sure. the sparks do not have to last long, just about 1 sec, max. the purpose of this simple contraption? i want to create a sustained jacob's ladder, rather than one lasting only a second (as the described contraption does). so what this contraption will do is apply the breakdown voltage, ionizing the air and then the sustained high voltage will be supplied by my DC arc welder that outputs 25V @ 50A. don't worry, i won't put the two to be electrically parallel to each other. the contraption has to be very cheap (would simply winding a step-up transformer be enough)?? i've tried different sources, the cheapest i found was simply buying a cheap stun gun (around $10-20) than can supply a few million volts -- pretty good. but the laws in canada does not allow the trade of any sort of weapon (even for self defense) whatsoever. i've tried looking at neon sign transformers but they cost at least $50.
    1 point
  44. thanks hero999 is there any formula for this issue? my coil is 57ohm
    1 point
  45. No, lead acid batteries are far too heavy. I was looking at maybe NiMH or more likely some LiPo batteries commonly used on RC cars and the like. Looking at 3-6AmpH class batteries. Might lean towards 12V, since there is so much standard stuff for that as far as wiring and other components. Safety is of course important and any good suggestions on grounding/shielding are welcome and appreciated.
    1 point
  46. 10,000V at 0.02A is 200W which is a lot of power for a little power supply.
    1 point
  47. Here is the book in pdf for you all. You can press the free button and you have to wait about a minute then it gives you the links. Just pick one. http://rapidshare.com/files/3372603/Practical_Electronics_for_Inventors.pdf
    1 point
  48. after removing of ebook files, the page is not visited so much and not updated messages as before...
    1 point
  49. Here is all I have Playstation2_Repairguide.pdf
    1 point
  50. Hi Maliki, National Semi doesn't have a spicy ( ;D) model for their LM3914. I looked on Google for Spice and then Pspice Model For LM3914 and found many people asking for a model too. One guy found a similar model to pspice online at a university. There are many French links. Parlez vous francais? Not me, and I hate Google's horrible translator. ;D
    1 point
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