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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. But even if we disable debug, it will call print method and do not print anything. I mean we should make it something like #ifdef DEBUG Serial.print("\n debug controlled print"); #endif Here when we disable macro, its like code is not written for compiler, code will be removed in macro processing itself.
    2 points
  4. 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
  5. Thanks for sharing your project with us. Could you give more details on the control board?
    2 points
  6. 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
  7. 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
  8. I use copper wire, not rice wire. They put rice in everything they make, especially batteries.
    2 points
  9. So Finally which version of schematic is correct / flawless to build the PSU ?
    2 points
  10. February 23 above on this page has the latest schematic of the revised 3A lab power supply.
    2 points
  11. Does anyone has LM3914 pspice library? i desperately need it..pleeeeease!
    2 points
  12. 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
  13. Illegal content (ebook/magazines/software) will be deleted without any notice. Thanks
    2 points
  14. 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
  15. 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
  16. 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
  17. 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
  18. I can't find SL100 & SK100 transistor :'( Which transistors can replace these? Thank you for your help~ ;)
    2 points
  19. 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
  20. I ordered a LYG55T024FS52S motor (https://www.hurst-motors.com/lyg55geared.html), but I misread the information about the capacitor. I thought it said capacitor was supplied with the motor, but that was only for the 115 VAC motors. Since I ordered the 24V, mine did not come with a capacitor. So I’m looking to buy one. The spec sheet says I need a 20/15 mfd 50/60 Hz capacitor. This is the closest I’ve found: http://www.mcmaster.com/7245K721/ Will that work for this purpose?
    1 point
  21. https://search.yahoo.com/search?p=2381BG-2-6&fr=opensearch
    1 point
  22. W25Q32 refers to a specific model of serial flash memory produced by Winbond Electronics Corporation. In particular, the "W25Q32" is part of the W25Q series, which consists of a range of flash memory chips differing in capacity and features. Standard SPI Instructions: The W25Q32JV is accessed through an SPI-compatible bus consisting of four signals: Serial Clock (CLK), Chip Select (/CS), Serial Data Input (DI), and Serial Data Output (DO). Standard SPI instructions use the DI input pin to serially write instructions, addresses, or data to the device on the rising edge of CLK. The DO output pin reads data or status from the device on the falling edge of CLK. SPI bus operation Mode 0 (0,0) and 3 (1,1) are supported. The primary difference between Mode 0 and Mode 3 concerns the normal state of the CLK signal when the SPI bus master is on standby and data is not being transferred to the Serial Flash. For Mode 0, the CLK signal is typically low on the falling and rising edges of /CS. For Mode 3, the CLK signal is usually high on the falling and rising edges of /CS. Dual SPI Instructions: The W25Q32JV supports Dual SPI operation when using instructions such as "Fast Read Dual Output (3Bh)" and "Fast Read Dual I/O (BBh)". These instructions allow data to be transferred to or from the device at two to three times the rate of ordinary Serial Flash devices. The Dual SPI Read instructions are ideal for quickly downloading code to RAM upon power-up (code-shadowing) or for executing non-speed-critical code directly from the SPI bus (XIP). When using Dual SPI instructions, the DI and DO pins become bidirectional I/O pins: IO0 and IO1.
    1 point
  23. Why not read books that interest you? For example:: Digital Design and Computer Architecture
    1 point
  24. Introduction Arduino IDE is a convenient tool to write your code and upload to microcontrollers. However, it doesn’t come with debugger function, which means the only way to debug our program is through using debug message through standard output, in this case, Serial Monitor. Debug message is handy and it helps to print out the information the registers holds at a specific time, but once you have done debugging and your program is ready to go, we often have to delete/comment out those debug message code manually, in a big project, this could be problematic as there are just too manny of them. Today, I am going to show you an easy method to turn on / off debug message with only a few lines of code. Method Take a look of the following C code, //#define __DEBUG__ #ifdef __DEBUG__ #define DEBUG(...) printf(__VA_ARGS__) #else #define DEBUG(...) #endif Since all Ameba microcontroller supports printf(), we can re-define printf() to a preprocessor function, in this case, I name it DEBUG(). Whenever you want to print out the debug message, instead of Serial.print() or printf(), you should try using DEBUG() instead, it works just like the previous two, but can be easily enabled or disabled by uncomment //#define __DEBUG__ or just leave the comment syntax there. Let’s look at an example Example code 1 This is a simple code that only print out “Debug msg 1” and “Debug msg 2” alternatively with a 1 second delay in between. Screenshot 2021-01-22 1639441919×1079 173 KB Note that the first line of the code is uncommented, and we are seeing the debug messages actually got printed out using the DEBUG() function. Example code 2 Screenshot 2021-01-22 1641171920×1077 127 KB Note that this is the same code except I keep the first line commented out, and as a result, no debug messages got print out at all. It works! Conclusion All you need to do is to copy the few lines of code from above into the top of your arduino sketch and you may name your custom debug function anything you like and it will work like a charm. Turn on / off is just to keep / remove the // at the first line, very convenient. Hope you like this content, stay healthy and happy coding~
    1 point
  25. I am confused with the two SIDACs (Silicon Diode for Alternating Current) in series. They are rated 220-250 volts switching each. 240 mains voltages would be in the order of 340*1,4 or 480 volts peak. About the same as the two SIDACs; not much to switch with? "These tasks of the starter are taken over by two 135 V sidac (or a single 270 V one). The starting voltage is thus 270 V, Which is below the peak value of the mains (about 340 V), but higher than the working voltage of a 20-40 W neon tube." see: https://circuit-diagramz.com/sidac-neon-tube-starter/ I will look at the circuit some more.
    1 point
  26. Hi, where can I find datasheet of STK407-070B? I just want to make a home made amplifier. thanks :D
    1 point
  27. 1 point
  28. The original project used a 24VAC transformer and TL081 opamps that have a maximum allowed supply of 36V. Since the project was not able to produce 30VDC at 3A because the supply voltage was too low, I changed the transformer to 28VAC and changed the opamps to TLE2141 that have a maximum allowed supply of 44VDC. Please post a video of your TLE2141 opamps blowing up if you power them from the 66VDC produced from rectifying the 48VAC from your wrong transformer. Or just parallel the two 24VAC secondaries which produces a rectified 32VDC so that the maximum regulated output from the project will be about 25VDC at 3A. The TLE2141 U2 gets warm, not hot because its output current is fairly low since it drives the driver transistor Q2 that drives the output transistors to 3A.
    1 point
  29. The 24VAC transformer has an output voltage too low for this power supply to produce 30VDC at 3A. The regulation will fail and there will be lots of ripple in the output at and above about 25V at 3A. I recommended a 28VAC or 30VAC transformer and higher voltage opamps years ago. For an output up to 5A then the transformer max output current should be 7A or more, the main filter capacitor C1 value should be about 17000uF or more, there should be 3 output transistors each with its own emitter resistor, a larger heatsink for the output transistors and change the value of R7 from 0.47 ohms to 0.27 ohms. I finished making improvements on this project in July, 2014 but others have made more changes.
    1 point
  30. audioguru

    battery level indicator

    The LM3914 in a DIP case is not made anymore. Buy them before they are all gone.
    1 point
  31. Thanks for the resources!!! I am currently working on the project "Electronic circuits of information collection and processing systems". The topic is very interesting, since I need to investigate the development of the linearizer of the first sensor with smooth and piecewise-linear approximation. It is also necessary to determine the value of the DC component extraction device from the signal of the second sensor. In addition to your recommended resources, I also used the writingcheap.com service, which helped me with the theoretical part of my work of developing an analog-to-digital converter. Using the information of this site http://www.analog.com/en/products/analog-to-digital-converters.html I was able to summarize the results of my research. You have an extremely helpful channel for students on YouTube. You have an extremely helpful channel for students on YouTube.
    1 point
  32. In PCBWay, the boards are good quality and pricing is great while OSH Park is an aggregator. They collect your board files and panelize them with others to get a good price. And in case of Smart-Prototyping, especially their PCBA services. Their service is very affordable.
    1 point
  33. Drill a hole on top of the mailbox and insert a ----> Without its pole. Optional, add a door switch for the LED. Done fast for $1. Some silicone sealant may help.
    1 point
  34. http://www.talkingelectronics.com/projects/SolarLight/SolarCharger-2.html
    1 point
  35. 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
  36. monkfinger

    0-30V 0-3A Latest Data

    Hi all Ok, this is my end result. Built and tested and works quite well. I started with the version posted at the start of this thread. However I had a couple of problems with the current limiter. I didn't have much success with the current limiter clamping the input of U2 - sometimes it would not go right down to 0V, sometimes it would go just below. Just below was a big problem for me - U2 would start to oscillate, with bad consequences for anything connected to the output of the Q4... It would then drive the output high just when I wanted the current limit to become active I should add that I did not use TL2141 or MC34071s, this might be the root of my problem. I fixed this issue with a small change to circuit layout rather than going to expensive opamps. My mods (compared to the circuit posted on start of this thread): * current limit - I removed D9. To replace this, I added another BC548 - the base is driven by the current flowing through the current limit LED. The collector of this BC548 clamps the output of U2 (exactly like the existing BC548 driven by the negative rail). This arrangement means we don't care how close to its supply voltage the output of U3 can go. It avoids the possibility of driving the input of U2 out of spec. Clamping the output of U2 is much more like how the integrated voltage regulators work. It seems better to my mind, to keep U2 out of the loop when current limit is active. [Edit: note that U2 will need a small heatsink with this arrangement] * some rearrangement of the opamp power connections, for all three opamps... U1 & U3 are run via 15V zener diodes, to give a supply of approx 30V. That allows almost any cheap opamp to be used for U1 & U3 (741s or TL071 etc). U2 is connected to unregulated 44V and to the output side of the 0R47. * I used a MC33171 opamp for U2. It is high voltage, but much cheaper (they are £0.60 in UK) than TL2141 or MC34071 (both are £5 here). It is a low power IC by comparison. * 0-30V 4A transformer. * 2 x 6800uF smoothing caps.a big thanks to the contributors on this thread for their efforts, my project was greatly speeded up by borrowing a lot of their ideas Edit: * I also changed the 0R47 to 0R2, as the 0R47 generated too much heat at 3A for my liking. This also means R18 changes to 330K. These two values are not shown on the schematic here.
    1 point
  37. Looking for an Ultrasonic Cleaner schematic. Gokar
    1 point
  38. admin

    LM3914 pspice library

    Here are two SPICE models found online that will simulate the main IC functions including:- a) bar/dot mode selection, dot mode carry for cascaded ICs, c) resistor-programmed hi/lo reference voltages, d) output current selection, e) non-grounded V- and divider ladder, f) independent V+ and Vled, g) leakage current of outputs, h) segment overlap and i) supply current variation with V+ and Vref output load. This model is build by user "alec_t" at electro-tech-online.com forum. LM3914.zip LM3914asc.zip
    1 point
  39. 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
  40. Guest

    0-30V 0-3A Latest Data

    Continued
    1 point
  41. Guest

    0-30V 0-3A Latest Data

    Continued
    1 point
  42. darrins

    PWM using 555 timer

    I read several datasheets and application notes on 555 timers, but I can't seem to find the information I'm looking for. Specifically, I'd like to use the 555 as a pulse width modulator by using the control voltage (pin 5). The datasheets indicate that in monostable mode, the output pulse width can be varied by modulating the voltage at pin 5 (V5). They also indicate that in astable mode, modulating V5 will modulate pulse position. What I'm wondering is this: What is the relationship between the control voltage, V5, and the values of the timing resistors and caps? There are standard formulas for timing based on these resistors and caps. How are those formulas affected by the introduction of V5? Thanks. Darrin
    1 point
  43. BTY79 NTE Replacement BTY79-800R = NTE5531 BTY79-600R = NTE5529 BTY79-500R = NTE5529 BTY79-400R = NTE5527 NTE Datasheet http://www.nteinc.com/specs/5500to5599/pdf/nte5520_31.pdf C106D = NTE5457 NTE Datasheet http://www.nteinc.com/specs/5400to5499/pdf/nte5452_58.pdf Try these suppliers Digikey --- http://www.Digikey.com Mouser --- http://www.Mouser.com Newark --- http://www.newark.com MCM Electronics --- http://www.mcmelectronics.com
    1 point
  44. 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
  45. so let me get this right. Theres a slight power difference in one Tda2003 to another even though there the same. but with a 8pin dual amp would work better cause there together in one IC.
    1 point
  46. I am very sad too :-[ [move] :'( :-[ :-\ :'( :-[[/move] No doubt, ER has been the one of most attractive features of the site. All the thanks and respect goes to Mr. Ante for such a good contribution to this part of site. I now request MIXOS to leave the contents as it is not reasonable to throw away ones friends(books).
    1 point
  47. Pin 8 of the IC should be 5.0V which is the output of the 78L05 voltage regulator or the 6V battery voltage. If you use the voltage regulator and D1 in series with it, then the minimum input voltage is 8.2V. Don't use a 9V battery because its voltage quickly falls lower. The micromitter has an attenuator of 3 resistors at its output to reduce its range. Remove the attenuator for much greater range.
    1 point
  48. ante

    PWM using 555 timer

    Darrin, Can this help you? Ante ::)
    1 point
  49. I attach it here also for fast view...
    1 point
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