hybridfree/eevblog-posts huggingface dataset:
Protecting biases from feedback - Page 1
Forum section: electronics / beginners

author: LoveLaika
author_rank: Frequent Contributor
timestamp: November 24, 2021, 05:33:20 am
content: I work with some silicon photomultipliers a lot, and they need to be properly biased at the right voltage in order to work correctly. In my cases, this involves adding a voltage at the cathode/anode. I typically pass the bias voltage through a 2nd-order Low Pass Filter (RC), and that's good enough usually. The trick is when you put two or more SiPMs in parallel.When working with two or more SiPMs, rather than connect the common cathode/anode together, I tend to pass the voltage through their own separate LPF for each separate diode (though there are instances where I can't, when the common bias points are connected together already). I found that if the capacitor values of the LPF are not large enough, the current from one SiPM will affect the others (this was evident when common bias points were already connected together). Thus, increasing the cap values reduces the 'crosstalk'/'feedback' amongst the SiPMs.However, I wonder if there isn't a better way, to have each bias voltage separate on each SiPM in order to prevent 'crosstalk'/'feedback'. One way I thought of was using an adjustable linear regulator for each sensor. The thing is, the bias voltage that I want will be the same as the input voltage going into each regulator. Theoretically, if I make it so that the regulator has the largest gain via resistor ratios, then the output should be the same voltage as the input. Setting it up like that, would using a linear regulator like that provide some kind of protection?
Protecting development boards against short circuits during prototyping - Page 1
Forum section: electronics / beginners

author: bodzio_stawski
author_rank: Regular Contributor
timestamp: February 14, 2024, 12:37:42 am
content: Hi!I would like to ask you to share your experiences. I'm talking about development boards and ways of securing them. When connecting such boards to something external, there is always a risk of damaging the board (e.g. the microcontroller on it), which will result in a short circuit.And while other types of boards are connected to a laboratory power supply with a current limiter, development boards are almost always powered from the USB port and with a USB current meter, we can observe a sudden increase in current during damage.Due to the fact that development boards available on the market may have varying degrees of protection - or almost no protection at all - I would like to ask you if you have any cool tricks for securing development boards from the USB port side? Something like a fuse or current limiter like below? Or any other simpler or more complicated methods?https://www.mikroe.com/current-limit-6-click

author: mawyatt
author_rank: Super Contributor
timestamp: February 14, 2024, 01:56:46 am
content: If you can run the USB port power from a lab supply with current limit set just above normal operation and with a lab supply with low output capacitance, this should help.Best,

author: JustMeHere
author_rank: Frequent Contributor
timestamp: February 14, 2024, 02:23:19 am
content: Your USB port should be protected. After all, a fault in the cable itself is very likely to happen given enough time. I know cheap HP boards protection is shit.They do make USB isolators. I had to use on some inventory scanners because they would kill the mobo if connected to anything other than USB 1.
Protecting gates and properly grounding P-Mos UPS circuit? - Page 1
Forum section: electronics / beginners

author: Russbo
author_rank: Newbie
timestamp: April 01, 2017, 07:57:59 pm
content: Hi there.I'm trying to put together a P-Mos UPS circuit to switch between a 5 cell lithium battery (16-21V usable range) and a 24V AC/DC power supply.I found a design from an old post (https://www.eevblog.com/forum/chat/battery-backup-circuit/) that somebody found from the schematic for the Tinyduino. For a 5 and 3.3V pair of sources, this works great. However there are issues I'd have using this design with beefed up FETs:1. I have a lot more potential in my circuit, if I pulled the battery FET to ground as this circuit does, I believe I would exceed the Vth of virtually any MOSFET and break it.2. The circuit simulates well if I replace the 5V with a grounded 24/0V dc source. However, if I instead use a constant 24V source with a switch inline, when I break the connection (unplugging my power supply in the real world), I get a range of strange voltages between 13 and 17V instead of the expected 0V where the DC supply was disconnected and this is fed into the gate of the N Mosfet, turning it on when I don't want it on. Current still only appears to flow through from the battery to the load but I don't think this behavior is desirable.I can stop pulling the DC fet to ground simply by connecting a zener between the source of the N mosfet and ground to limit the voltage to the DC fet gate to say, 10V instead of 0V.I can't apply the same technique to the battery FET because it's using the DC supply to drive its gate and when the DC supply is removed, the only voltage there (should be) ground, so a zener won't work in this case.The image of the original circuit and my attempt are attached. Really any method that would work I'm happy with, even if it means increasing component count, using an MCU etc. I don't mind. All help is much appreciated. Thanks!

author: EPTech
author_rank: Regular Contributor
timestamp: April 02, 2017, 03:27:24 am
content: Yes indeed,Just put a zener of 15V with a series resistor of say 22k between source and gate and pull down the gate with another FET. That should protect your gates.Your FET's are the wrong way round. The sources should be connected to battery and external supply. The drains should be connected to Vcc.In case of the NTZD3152P, it already has ESD protected gates, just a series resistor will suffice.Happy designing.
Protecting PSUs in series - Page 1
Forum section: electronics / beginners

author: TeraHz
author_rank: Contributor
timestamp: April 02, 2012, 07:31:27 pm
content: Hi guys,I have two 24V 6.5A switching PSUs that I'd like to connect in series and tap in the middle to power two circuits, one at 48V (~2.5A draw) and one at 24V (about 1A draw).Apart from putting a diode across the output terminals of each PSU, what else is a good practice to do for protection?Thanks

author: PA0PBZ
author_rank: Super Contributor
timestamp: April 02, 2012, 08:01:52 pm
content: Well, you could have some fun (even with the diode) if you don't power them up at exactly the same time so maybe something that connects the load only after both are powered up? And make sure that the outputs are floating
Protecting SMPS and driving circuit from inductive loads (motor) - Page 1
Forum section: electronics / beginners

author: amaschas
author_rank: Regular Contributor
timestamp: June 14, 2022, 04:33:10 pm
content: Hi all, I have been working on a project that involves driving a 24V/1A (max under load) geared motor bidirectionally from a SMPS. I've been trying to understand what exactly is involved in protecting the power supply from the various conditions that can arise from inductive loads and getting a bit confused. From what I understand, when a motor slows or reverses, the energy stored in the coils need somewhere to go, and so the circuit that controls the motor needs to be able to absorb that energy somehow. My application involves turning the motor one direction for a few seconds, and then reversing it and turning it the other way, under load the entire time. If I understand correctly this kind of a worse case scenario for back EMF. The motor will be rotating fairly slow, < 60 RPM, and it is is geared which IIRC mitigates this issue somewhat, but I feel like I'm still going to need some kind of back EMF protection.The driver I am using is a MAX14870 (https://www.pololu.com/file/0J885/MAX14870.pdf) which seems way too tiny to be able to drive a motor, though the specs are well above what my motor requires. It advertises free-wheeling diodes, but if I understand correctly those only clamp the voltages under the level that would damage the _driver_, and I'm actually not quite clear on whether those diodes actually absorb any energy. I'm wondering if I need some sort of circuit to feed any excess energy into a beefy resistor, or if the driver itself is sufficient to handle the motor load in my case. I'm considering a scaled down version of this circuit:https://drmrehorst.blogspot.com/2022/05/bank-account-protection-circuit-for.html, though without the capacitor since the IC data sheet specifically notes "Maxim does not recommend using external capacitors across the motor terminals. Added capacitance between H-bridge outputs increases the power dissipated in the H-bridge".Alternatively I am considering a MOV like this one:https://www.digikey.com/en/products/detail/eaton-electronics-division/MLVC13V024C1050/13687315
protection diode - Page 1
Forum section: electronics / beginners

author: snailFury
author_rank: Contributor
timestamp: December 21, 2013, 03:37:40 pm
content: Hi. I'm trying to find out if I am using this diode device correctly as a protection device against high voltage.I'm trying to use the diode as in the first attachment schematic. I want to use an arduino pin to send a voltage to the base of a transistor in order to complete a circuit that will close the switch in a relay that is controlling wall voltage (120V) powering other mechanics.I've read that the diode is necessary to protect the arduino when the relay switch closes.The second attachment image shows my breadboard. The diode is in the middle of four wires.Upper left and lower right wires (larger red) go to the switch on the relay.Upper right(smaller red with black cap) is 12V.Lower left(smaller yellow with black cap) goes to leg of transistor(collector).Is this diode connected properly to protect the arduino?thanks

author: madires
author_rank: Super Contributor
timestamp: December 21, 2013, 03:58:52 pm
content: Yes, you've connected the diode correctly. For more information on flyback diodes please seehttps://en.wikipedia.org/wiki/Flyback_diode.

author: Kjelt
author_rank: Super Contributor
timestamp: December 21, 2013, 04:00:17 pm
content: Yes connected ok, you can simply deduct it, if you place it the other way round you put Vrelay-0,6V on the collector and short it if you operate the transistorNow the diode only conducts if the voltage on the collector goes over the Vrelay+0,6V and the conducts it to Vrelay safely. Place it as close to the relay as possible.

author: snailFury
author_rank: Contributor
timestamp: December 21, 2013, 04:04:30 pm
content: thanks and thanks!

author: Macbeth
author_rank: Super Contributor
timestamp: December 21, 2013, 09:27:27 pm
content: Lots of relays come with the protection diode built in (or some cheaper ones use a parallel resistor). It's worth checking the datasheet. Certainly all the automotive "plug and play" relays I've encountered have some form of protection in them.

author: christopher iles
author_rank: Regular Contributor
timestamp: December 26, 2013, 06:19:50 am
content: Your diode is correctly placed. The reason you need it is that the back EMF from the relay coil when it de-energises can be as much as 40 TIMES the applied voltage, in your case 480v with a 12v relay. It is always good practice to put a diode across a relay coil as you have done.

author: ConKbot
author_rank: Super Contributor
timestamp: December 26, 2013, 02:21:49 pm
content: Quote from: christopher iles on December 26, 2013, 06:19:50 am+1 to that. I got my hand bit pretty hard once by a relay in a 24V vehicle that had been miswired and was oscillating. I heard the buzzing, and was feeling around in the confined space to find the buzzing thing. Turned it it was the relay, and my hand found the back of it, and it felt on par with grabbing 120V mains with one hand. But it was un-expected so it was quite startling.
Protection Diodes on 3 Terminal Regulators. - Page 1
Forum section: electronics / beginners

author: Lee Leduc
author_rank: Regular Contributor
timestamp: July 01, 2016, 05:09:11 pm
content: I have a question about protection diodes used on fixed and adjustable 3 terminal regulators.The attached image shows the datasheet recommended diodes for these 2 regulators. Should D?? be added to the adjustable regulator to protect it if the output falls below ground (negative) as D2 protects the fixed regulator?Thank you.

author: Gyro
author_rank: Super Contributor
timestamp: July 01, 2016, 05:37:31 pm
content: D?? isn't normally used unless there is also a negative rail in the system that might pull the output negative (maybe at power down). It really depends what the regulator is powering, you would probably want to include it if you were making a bench psu for instance.
Protection for frequency meter input - Page 1
Forum section: electronics / beginners

author: PinheadBE
author_rank: Regular Contributor
timestamp: September 09, 2023, 09:50:12 am
content: Hi,I scored an old ICM7216 based frequency meter, which is working very well.I do not have nor schematics, neither precise specs.The UHF input which goes through a prescaler (reference scrubbed off....) has a limitation of 3 V p-p (printed on the front panel)The overall bandwidth on this input is unknown (I do not have a sig gen that goes over 60 MHz), but will probably not exceed 100 MHzI was looking for a circuit to protect that input . There seems to already be two simple diodes, but they look so fragile (1N4148 like) that I do not trust them, and I would like to add some more beefy protection.I was considering figure 11 on this pagehttps://www.digikey.be/en/articles/protecting-inputs-in-digital-electronicswithout the cap, of course.But I would prefer to have some sort of "Automatic Gain" circuit which automagically keeps the amplitude within the 3 V p-p range.I suspect this must be fairly simple with an op-amp(s) based circuit, but my knowledge in analogue circuitry is too basic.Could someone help me with this, or point me to a page with some useful information ?Thanks a lot !

author: PinheadBE
author_rank: Regular Contributor
timestamp: September 09, 2023, 09:54:16 am
content: .... or simplier : A simple 2.9 V Zener and its series resistor ?Would this work without affecting the bandwidth (< 100 MHz) ?

author: ledtester
author_rank: Super Contributor
timestamp: September 09, 2023, 11:30:44 am
content: Generally frequency counters have an amplifier at the input because they are usually used with very low level signals -- like the mV RMS range.If you are concerned that a signal source may be too powerful you can always insert an attenuator to decrease it:#91: Basic RF Attenuators - Design, Construction, Testing - PI and T style - A Tutorial -- w2aewhttps://youtu.be/A5gGeV7CiQ0Some counters have a built-in attenuator you can activate with a switch.

author: Kleinstein
author_rank: Super Contributor
timestamp: September 09, 2023, 11:32:30 am
content: Zener diodes often have quite some capacitance. So they may load down a higher frequency signal quite a bit.The more usual way are diodes like the 1N4148 towards some voltage (zener or string of diodes with a bias current).The diodes are ususally not that bad and tend to fail short unless there is really serere overcurrent (e.g. > 1 A for a 1N4148).

author: PinheadBE
author_rank: Regular Contributor
timestamp: September 09, 2023, 12:03:45 pm
content: Thanks for your answer.I intend to use this meter also to test logic signals that can go up to 5 V. Therefore, I would prefer not to rely on the original protection: this was already a cheap meter in its time, and since the markings are not readable on the prescaler chip, I would not like to have it releasing its magic smoke....I will take a look at that YT video.Have a nice day
Protection for GPS input - Page 1
Forum section: electronics / beginners

author: rakeshm55
author_rank: Regular Contributor
timestamp: May 11, 2019, 12:31:42 pm
content: Hi,How to protect Antenna input signals from ESD?I have connected a low capacitance ESD diode. What is the standard mechanism used to protect GPS module (Sensitive to ESD) from ESD faults.

author: Yansi
author_rank: Super Contributor
timestamp: May 11, 2019, 02:25:05 pm
content: You have your answer on the schematic.Other option is to use a diode clamp.

author: dmills
author_rank: Super Contributor
timestamp: May 11, 2019, 02:46:06 pm
content: A Quarter wave stub to ground should work and can be printed right onto the board.regards, Dan.

author: radiolistener
author_rank: Super Contributor
timestamp: May 11, 2019, 03:54:33 pm
content: Here is typical solution to protect from overvoltage. In your case, you can use 1:1 RF transformer.

author: Yansi
author_rank: Super Contributor
timestamp: May 11, 2019, 05:39:11 pm
content: Quote from: dmills on May 11, 2019, 02:46:06 pmWill ruin impedance matching and will work likely only rather narrowband.Also please keep in mind that GPS is like what... 1600MHz? The 1/4 wave stub will be unacceptably long for most applications on a PCB.

author: dmills
author_rank: Super Contributor
timestamp: May 11, 2019, 07:07:32 pm
content: GPS is rather narrow band, CA is only a MHz wide so less then 0.1% fractional bandwidth, and at ~1600MHz a quarter wave shorted stub will be less then 4.5cm long.I don't see a problem with a stub line, and if you play it right you can also use it as the choke for the DC to power the antenna LNA.Regards, Dan.
Protection requirement for battery charger - Page 1
Forum section: electronics / beginners

author: Freshman
author_rank: Regular Contributor
timestamp: February 14, 2025, 05:17:41 am
content: Any idea on whether the MCP73832 IC (https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/MCP73831-Family-Data-Sheet-DS20001984H.pdf) can be used to charge a battery pack with two cells in series?Typically, battery protection circuits include individual cell voltage monitoring to prevent cells from exceeding their maximum voltage, which could lead to thermal runaway.How to check whether the MCP73832 is designed for 2S cell packs? Going through the datasheet I think it lacks the ability to measure the voltage of each cell separately. How to check whether there are any safety mechanisms are in place that eliminate the need for individual cell monitoring? Would you recommend pairing this charger with an additional battery management IC for enhanced protection?Edit: Correct datasheet and part number is MCP73842 ,https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/21823D.pdf. My apologies.

author: Zipdox
author_rank: Regular Contributor
timestamp: February 14, 2025, 06:12:27 am
content: It clearly says fully integrated single cell, so no, it can't be used for two cells in series. There are also dual cell charge ICs.

author: squadchannel
author_rank: Frequent Contributor
timestamp: February 14, 2025, 06:35:49 am
content: "MiniatureSingle-Cell, Fully Integrated Li-Ion, Li-Polymer Charge Management Controllers"

author: Freshman
author_rank: Regular Contributor
timestamp: February 14, 2025, 12:39:17 pm
content: My apologies, this is the correct datasheet and part number:https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/21823D.pdf, which can use to charge 2 cells. MCP73842.
Protective Backing  - Page 1
Forum section: electronics / beginners

author: sdscotto
author_rank: Contributor
timestamp: May 14, 2011, 11:42:18 pm
content: I'm looking for a source for single sided sticky foam backing. It goes on the back of a PCB. It looks like this:Does anyone know what this material is called and where to get it?Thanks in advance,scotto

author: tecman
author_rank: Frequent Contributor
timestamp: May 14, 2011, 11:54:32 pm
content: Adhesive backed foam !Look in a craft store. Readily available, and cheap.paul

author: sdscotto
author_rank: Contributor
timestamp: May 15, 2011, 12:45:19 am
content: Thank you!

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 15, 2011, 02:56:22 am
content: and if you cannot find the adhesive backed foam. then find a normal foam (without adhesive), and buy a double sided tape, stick them together the you got the above mentioned foam.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: May 15, 2011, 11:20:45 am
content: Quote from: Mechatrommer on May 15, 2011, 02:56:22 amThere is out there high quality tape,just search on eBay about :SEKISUI 5760Thermal Adhesive1) Special characteristics about holding well in hot surfaces2) Made in Japan.

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 15, 2011, 12:12:06 pm
content: Quote from: Kiriakos-GR on May 15, 2011, 11:20:45 amno need ebay. even my place at the edge of the world here, i still can find decent functional tape. and i usually heat the adhesive before sticking it for stronger adhesion. adhesive works better in hot condition.
Protective earth clearance/creepage distance - Page 1
Forum section: electronics / beginners

author: chagli
author_rank: Contributor
timestamp: March 18, 2019, 02:01:39 pm
content: Hi,I am working with 'new' safety standard IEC-62368.I don't know if protective earth is classed ES1 (energy source class 1) as it is typically accessible by the end user. Or maybe it has no predefined class and creepage and clearance distances relative to earth must be solely computed from voltages.Thank you.
Protek P-3502c help needed. - Page 1
Forum section: electronics / beginners

author: Recarta
author_rank: Newbie
timestamp: September 15, 2017, 09:25:00 pm
content: I purchased a Protek P-3502c. Thanks to Dave for the advice!It did not come with the leads. It only had a BNC to alligator clip and an AC current clamp....After reading a few forum comments, I purchased an appropriate set of leads. My question is..What leads/connector do I need for the component tester?I will attempt to attach a picture of the receptacle.I do hope it is something simple like a banana plug.
Proteus 8.7 set layer usage - Page 1
Forum section: electronics / beginners

author: Adrian_Arg.
author_rank: Frequent Contributor
timestamp: June 04, 2018, 01:44:45 am
content: Good, I need to know where this "set layer usage" is for a job and I am not able to find it, I put a video of what I need (min 0.55). The problem is that in the new version of the program 6.7 sp3 is not there. Thanks in advance.

author: Wilksey
author_rank: Super Contributor
timestamp: June 04, 2018, 11:18:10 am
content: First you need to set the stackup : Technology->Set Layer StackupThen when you have chosen how many layers you want you can go to Technology->Set Layer PairsThen you can configure you layer pairs.

author: Arturoizer
author_rank: Newbie
timestamp: June 06, 2018, 03:31:25 am
content: The content of the community is very useful to me, how can I find out where else?

author: Wilksey
author_rank: Super Contributor
timestamp: June 06, 2018, 11:37:08 am
content: How can you find out where else what?Are you looking for something in specific?This forum has multiple sub categories that you can browse / post to depending on what you need.
Proteus design pcb layout problem - Page 1
Forum section: electronics / beginners

author: zzlong94
author_rank: Contributor
timestamp: April 04, 2018, 02:19:28 pm
content: i had a few problem with my pcb layout designthe pcb layout of mine hv the shape and name of each component that i had place.any method to remove the name or the shape of the component to prevent it from short circuit?thx.

author: Buriedcode
author_rank: Super Contributor
timestamp: April 04, 2018, 11:52:42 pm
content: I have never used proteus before, but it appears you have printed your layout and included the top (and maybe bottom) silkscreen, which is often used for component placement, name, and value (like R1 10k).I quickly googled and came across this post on stackexchange:https://electronics.stackexchange.com/questions/41543/print-a-pcb-layout-several-times-in-the-same-sheet-at-once-in-proteusIt shows a dialogue where there are tick boxes for the layers to be included in your print out. If you are etching your own boards and printing this for "toner transfer" or UV exposure, then you should only have the "bottom copper" ticked - assuming your board has only the bottom layer. Uncheck both the "top silk" and "bottom silk"

author: zzlong94
author_rank: Contributor
timestamp: April 05, 2018, 04:41:16 am
content: Thx a lot bro for ur useful information.Finally, i had finally remove the shape and the name of the component.U hv help me a great job.all the best to you!:)
Proteus ISIS or Altium designer summer 09? - Page 1
Forum section: electronics / beginners

author: nasrmiad
author_rank: Contributor
timestamp: February 05, 2012, 03:33:16 pm
content: Which do you think is better for schematics and simulation? I was thinking of doing the schematics in Proteus ISIS and then transferring to Altium for the PCB design. What do you think?

author: EEVblog
author_rank: Unknown
timestamp: February 05, 2012, 11:49:57 pm
content: Altium is hopeless for simulation.You can make it work, kinda, but it's painful.Never used Proteus, so can't comment.I use LTspice for simulating small sub-circuits where needed.Dave.

author: logictom
author_rank: Unknown
timestamp: February 06, 2012, 11:14:24 pm
content: I've never used either for simulation - again only ltspice.Where I work they bought ISIS but dropped it in favour of Altium. I've only used Altium and so far haven't had many issues with it.

author: DLWarr
author_rank: Newbie
timestamp: January 28, 2019, 03:23:52 am
content: Well, I use All,,Proteus, Altium, LTSpice... For simulation Proteus is absolutely the best for Microprocessor based design, You actually write your software for the processor then add it to the possessor in the simulation, and you can mix it with desecrate components etc.Altium is best for FPGA design, but not that great with the simulations.. and LTSpice has become best for desecrate (specific Purpose ICs, op-amps, transistor,ect) simulations..For PCB design work Altium is the Best and the defacto, Followed by Proteus, and LTSpice has no PCB capability...LTSpice is a Must have,,, and although free, it is used by design engineers around the world to communicate their design Ideas with each other, as every one has it...Proteus is best for all round simulate and then convert to a PCB...Altium is best if you want to design PCB's for a living.. It is the most time extensive and complex to learn of the 3, but top grade PCB's...When selecting design software its good to keep in mind that if you, for any reason leave the field for a time, it can be difficult to re-educate yourself to your complex software....

author: dmills
author_rank: Super Contributor
timestamp: January 28, 2019, 06:59:01 pm
content: The thing is simulation is mostly useful for confirming that you have not made a thinko on things like filters and control loops, it is of very limited use on jellybean circuits because it is only ever as good as the models, and beginners do not really seem to get this.I nearly never simulate more then a dozen components at a time, you know, is that MFB filter actually right? Is that loop stable? Those kinds of questions for which simulation is good, but generally going in I know what I am expecting to see. Simulation is great for telling you something will not work, but any sim reporting that something will work should be read as a 'maybe'.I find Proteus (And I have had to use it) inferior in all ways to even old AD plus spice of choice, or even something like (Spit!) Pads/DxD, and it takes something to make me consider DxD to actually be more useful.... Both Altiums nod toward simulation and their FPGA tools are not worth the time however.Regards, Dan.
Proteus optocouplers - Page 1
Forum section: electronics / beginners

author: Brigadir
author_rank: Newbie
timestamp: April 04, 2020, 09:55:59 pm
content: Guys, how can I add any of these optocouplers to Proteus?https://eu.mouser.com/Optoelectronics/Optocouplers-Photocouplers/MOSFET-Output-Optocouplers/_/N-awss6?P=1yocruu

author: Jwillis
author_rank: Super Contributor
timestamp: April 05, 2020, 05:15:47 am
content: I seems the libraries are supported by most ECAD tools including Proteus . You used the Library Loader to convert to your ECAD tool format. I could be wrong .

author: Adrian_Arg.
author_rank: Frequent Contributor
timestamp: April 06, 2020, 02:50:32 pm
content: I have proteus 8.9, when you go to the component database it connects you to a site and automatically downloads them if you have the network license activated.
ADC measuring  - Page 1
Forum section: electronics / beginners

author: kingkings
author_rank: Newbie
timestamp: June 30, 2020, 02:58:32 pm
content: hello A friend of mine needs help with this questionA temperature transducer that outputs 10 mV / oC is used to measure the temperature in a room ranging from 0 to 100 oC.sensor information is given to the Analog input of two different ADCs.ADC1: 8 bit, nominal input range 0- 5 volts,ADC2: 12 bit, nominal input range 0-10 voltsand he have to measurea) What is the resolution of each of these ADCs (voltage value you can measure, i.e. step size)?b) How the bit resolution varies depending on the temperature range for both ADCs.c) If ADC1 created a binary code (1110 0010), what is the input voltage range that can generate this code?d) If ADC2 created a binary code (0000 1110 0010), what is the input voltage range that can generate this code?e) Find the codes produced by two ADCs: (i) 3.5V (ii) 2.35 and (iii) 6.35 V Input voltages:if u can help you are so welcome otherwise do not comment , thanks

author: radiolistener
author_rank: Super Contributor
timestamp: June 30, 2020, 03:19:11 pm
content: Quote from: kingkings on June 30, 2020, 02:58:32 pmit depends on ADC clock speed, clock jitter and ADC properties.You're needs to measure dynamic range of your ADC, then you can calculate it's effective resolution:ENOB = (SNR - 1.76) / 6.02where SNR is measured dynamic range of your ADC in dB.

author: radiolistener
author_rank: Super Contributor
timestamp: June 30, 2020, 03:30:19 pm
content: Quote from: kingkings on June 30, 2020, 02:58:32 pmit depends on reference voltage Vref, ADC bits resolution and output format, for unsigned integer, it will beVoltage = Value * Vref / 2^NBut actual value may be a little different, just because real ADC may have some nonlinearity.

author: kingkings
author_rank: Newbie
timestamp: June 30, 2020, 08:41:32 pm
content: Quote from: radiolistener on June 30, 2020, 03:30:19 pmfor e,c,d assuming appropriate voltages from the range given for adc 1 and adc 2 may you explain more , as which provided above is the whole question nothing more , also maybe a hint for B

author: JustMeHere
author_rank: Frequent Contributor
timestamp: July 01, 2020, 08:04:49 am
content: Is this your homework?

author: mikerj
author_rank: Super Contributor
timestamp: July 01, 2020, 10:05:14 am
content: Quote from: JustMeHere on July 01, 2020, 08:04:49 amIt's a"friend's"homework

author: kingkings
author_rank: Newbie
timestamp: July 01, 2020, 10:56:29 am
content: Quote from: mikerj on July 01, 2020, 10:05:14 amexactly

author: garethw
author_rank: Regular Contributor
timestamp: July 02, 2020, 03:06:34 pm
content: For ADC1 which is 8 bits, assuming a VRef of 5V:2^8 =256 values5 / 256 = 19.5mV per LSBRange = 0V - 4.98VHopefully you can work the other one yourself 👍🏻
Prototyping RF Circuits - Page 1
Forum section: electronics / beginners

author: krivx
author_rank: Frequent Contributor
timestamp: September 10, 2013, 03:46:10 pm
content: I need to duplicate a circuit that has adds ~400MHz signal to an input DC signal. The VCO and bias tee are built using parts from Mini-Circuits so I'm not too worried about the component choices, however the original build was done on pad-per-hole veroboard. If I duplicate this, am I better off using a construction technique better suited to high-frequency circuits? Should I be looking at dead-bug/manhattan style builds instead of a direct copy of the original?
Prove me wrong (solved)( voltage doubler, redundant diodes) - Page 1
Forum section: electronics / beginners

author: Raj
author_rank: Frequent Contributor
timestamp: November 12, 2019, 04:25:20 pm
content: I'm there commentator, 'Suraj Grewal' in this video.Prove the statement in the screenshot is working for schematic in that point of video.Video link-https://youtu.be/Rmq4OKhKX-4My statement... There will never be current flow across diode d3,d4

author: Raj
author_rank: Frequent Contributor
timestamp: November 12, 2019, 04:35:11 pm
content: Extra protection for capacitor?

author: Raj
author_rank: Frequent Contributor
timestamp: November 12, 2019, 04:47:10 pm
content: redrawn for clearity

author: AVGresponding
author_rank: Super Contributor
timestamp: November 12, 2019, 04:47:30 pm
content: This circuit is a bit of a mule, a hybrid of dual rail centre tapped half wave and single rail full bridge. Is it a single rail full bridge with a bodge to get a dual rail supply?

author: Yansi
author_rank: Super Contributor
timestamp: November 12, 2019, 04:52:36 pm
content: Just a damn classic voltage doubler with two useless diodes.

author: Raj
author_rank: Frequent Contributor
timestamp: November 12, 2019, 04:55:44 pm
content: Quote from: Yansi on November 12, 2019, 04:52:36 pmMaybe he did that on purpose, so that it becomes more memorable.

author: JackJones
author_rank: Regular Contributor
timestamp: November 12, 2019, 05:14:28 pm
content: Sometimes this circuit is used for products that work with both 120VAC and 240VAC.Drawn like this it would double the output voltage, but when you break the link between TP+ and AC- it would act as a full bridge rectifier for 240V (or 230V really) countries. Although for use with 230V there should be resistors across both the caps to balance out the leakage current.That might be where the mistake comes from, it's not an uncommon thing to see in various products as I understand it.

author: Raj
author_rank: Frequent Contributor
timestamp: November 12, 2019, 05:20:41 pm
content: Quote from: JackJones on November 12, 2019, 05:14:28 pmBingo....ive seen that in many smps power supply input side...would have made more sense if he was to put a switch there.

author: schmitt trigger
author_rank: Super Contributor
timestamp: November 12, 2019, 05:35:51 pm
content: This circuit (with a switch as mentioned above) was used for many years in the "silver box" PC supplies.The switch would modify the circuit as a voltage doubler (for 120VAC) or a full bridge (for 240 VAC).

author: soldar
author_rank: Super Contributor
timestamp: November 13, 2019, 11:06:52 am
content: Quote from: Raj on November 12, 2019, 04:25:20 pmPlease use descriptive titles in your threads.

author: Raj
author_rank: Frequent Contributor
timestamp: November 14, 2019, 10:01:07 am
content: Quote from: soldar on November 13, 2019, 11:06:52 amApparently I can still modify it... Suggest one.

author: Gyro
author_rank: Super Contributor
timestamp: November 14, 2019, 10:09:57 am
content: Voltage doubler, redundant diodes?
Providing too much V and I ( current? ) - Page 1
Forum section: electronics / beginners

author: Hextejas
author_rank: Frequent Contributor
timestamp: February 08, 2024, 07:37:55 am
content: Total newbie so please be nice.The issue came up when I was asked to furnish a 8V power supply to charge a car vacuum.I didn't have one, I had a 12, 14, 22, etc., so I answered no. and that made me endlessly curious .I was hoping that the circuit could handle any range of voltages and/or currents and would only draw what was needed,I know that cant be correct but i don't know why.Would someone please point me in the right direction ?Forever grateful.George

author: brucehoult
author_rank: Super Contributor
timestamp: February 08, 2024, 07:50:15 am
content: If the voltage is correct then there's no such thing as "supplying" too much current, only too little.The DUT will use the current it needs. If it needs more than your power supply is built to deliver then either the PS will start to output a lower voltage, or it will blow up (0V is also a lower voltage)If you supply too much voltage then a DUT with simple design (e.g. purely resistive load) will take more current in the same proportion. e.g. if you give 12V instead of 8V then it may also take 1.5x more current than normal, which multiplied together means 2.25x more power consumption and heat in the device. Some might handle this, many will fail.Pure excess voltage can also destroy some devices, even at low current.And of course some smarter devices will have their own active voltage regulation and/or current limiting and work just fine.

author: Zero999
author_rank: Super Contributor
timestamp: February 08, 2024, 08:09:56 am
content: Quote from: brucehoult on February 08, 2024, 07:50:15 amThat's true, but 8V is very close to the full charge voltage of two lithium ion cells, so it's possible it requires a battery charger, rather than a dumb 8V power supply. If so, then it will need to limit the current, depending on the battery capacity and voltage. Connecting it to an 8V supply, which is not current limited might blow it up.

author: brucehoult
author_rank: Super Contributor
timestamp: February 08, 2024, 10:40:43 am
content: Quote from: Zero999 on February 08, 2024, 08:09:56 amAbsolutely! You'd be crazy to use lithium cells without a proper charge controller, either built into the pack, or in an external charger.We don't know which is the case here.

author: Zero999
author_rank: Super Contributor
timestamp: February 08, 2024, 06:38:36 pm
content: Quote from: brucehoult on February 08, 2024, 10:40:43 amIt's possible the original poster requires something like this, but I can't be sure without more information: vacuum cleaner make/model, battery capacity etc.https://energylightbulbs.co.uk/replacement-8-4v-car-charger-for-rechargeable-flood-lights-torches-battery?utm_source=google&utm_medium=cpc&utm_campaign=Smart+Shopping&utm_id=12775947335&gclid=CjwKCAiAlJKuBhAdEiwAnZb7lc6t1MkKP1gGx3mExrCpq1VUkL4mgZgjjn7N6F25qSuc_z_q41A9_hoC-6AQAvD_BwE
Proximity sensors required for mini quadcopter - Page 1
Forum section: electronics / beginners

author: abhishekkumar1902
author_rank: Regular Contributor
timestamp: September 11, 2017, 06:28:21 am
content: I am looking for some really good industrial grade proximity sensors to be mounted on a mini quad (frame could fall anywhere between 90x90mm to 330x330mm) for obstacle detection and collision avoidance use cases.Distance measuring range should be well enough up to at-least 100-150cms. Although I have found some SHARP IR sensors which looks good though but still wanted to know if something better is available in the market, and optionally if they do work flawlessly in bright sunlight or in presence of overly IR prone areas.
PS3 Slim Voltage breaks down - Page 1
Forum section: electronics / beginners

author: Subtixx
author_rank: Newbie
timestamp: November 12, 2019, 01:40:46 pm
content: So I have a broken PS3 which has a red light, when pressing the on button it changes to green and beeps 1 time. After about a second the green light vanishes. Pressing the power button turns the PS3 to standby again.I’ve tested the voltage of the power supply and its 12V so thats ok. Then I tried powering the PS3 from a bench supply in CC mode. The PS3 tried to take more than 1A which I think is too high? Connecting the power supply & the bench supply (so power supply to the 5v of the power button and the bench supply to the PS3 12v itself) which did the same thing.The output of the PS3 supply shows 12V for 1-3 Seconds, after that it breaks down to 0. Which indicate that something on the board is shorting.The board is a KTE-001, I’ve tested all caps and coils which all tested was fine. Hopefully anybody has a new idea how to get to the bottom of this problemKind regardsSubtixx
PS5004 precision power supply question  - Page 1
Forum section: electronics / beginners

author: ExodusEffects
author_rank: Contributor
timestamp: August 17, 2018, 12:31:34 am
content: I’m fairly new to buying test instruments and I’d like to get one more power supply to be able to increase the amount of voltage or current available with my DP712. I love the rigol but I feel having one more small supply would definitely be beneficialMy main question is what would you say the value of a well working unit in good shape would be. I have the opportunity to import one from the states for $180 CND in total. It’s a .01% power supply with some additional built in features

author: ArthurDent
author_rank: Super Contributor
timestamp: August 17, 2018, 12:55:41 am
content: I assume you must have the 5000 series power module to plug this into because this is not a stand alone power supply. These supplies were made starting in the early 1980s so it is quite old. If you are looking for a 0-20.0000VDC power supply at up to about .3A it would probably work but I would be looking for something more capable and modern.

author: ExodusEffects
author_rank: Contributor
timestamp: August 17, 2018, 06:11:36 am
content: Yes I have the TM5006 but not the 5003, however I’ll need to do work in the TM5006. Needs a new fuse and ribbon cable among a few other small things, it was a gift ( assuming I could get what I needed for it ). Is it worth investing the time and money though do you think or am I better or to just sell the 5006 as is and invest the money plus what I have saved towards another much smaller unit
PSC Motor thin wire - Page 1
Forum section: electronics / beginners

author: justinjja
author_rank: Regular Contributor
timestamp: September 01, 2018, 06:51:36 pm
content: Why is the purple wire thinner than all the others?This is a blower motor from an HVAC.Thanks,Justin

author: justinjja
author_rank: Regular Contributor
timestamp: September 01, 2018, 06:57:54 pm
content: Nevermind,Even though the purple wire is less than half the size of the other wires,It is actually a higher AWG than the other wires, must have much thinner insulation.Still doesn't make sense to have less insulation, (Both legs are 120v here) but whatever...
Pseudo-Differential ADC - understanding reference voltages - Page 1
Forum section: electronics / beginners

author: Chris42
author_rank: Contributor
timestamp: July 28, 2022, 08:16:14 pm
content: Hello,I'm building a circuit that is supposed to measure light intensity using photodiode.For transimpedance amplifier I'm using the following circuit with Vbias set to 1.2V.For digitization I want to use MCP3561 24 bit Pseudo-Differential ADC (https://ww1.microchip.com/downloads/en/DeviceDoc/MCP3561.2.4R-Data-Sheet-DS200006391A.pdf).When there is not light, amplifier will output biasing voltage so I wanted to set up the ADC to measure difference between output and Vbias.Ideally Vbias would correspond to code 0 and Vbias + 2V would correspond to the highest code.My understanding is that I need to connect Vbias to Vin- and output from the amplifier to the Vin+. However I still have some troubles understanding how to connect reference voltages. This ADC has positive reference voltage and negative reference voltage.My question is what is negative reference voltage used for and how I'm supposed to connect the reference voltages in my case? Do I just connect 2V reference to Ref+ and call it a day or is it more complicated?

author: Kleinstein
author_rank: Super Contributor
timestamp: July 28, 2022, 09:12:27 pm
content: The ADC is more like true differential and can have both Ref- and Vin- to move quite a bit. Pseudodifferential would normally be with the negative sides with only a limited range (like +-0.5 V) - normally just used for slightly different grounds.The ADC does not need an extra negative supply to handle a negative input. So the ADC ref could be fixed like ref- near ground and ref+ at something like +2.5 V to get a range of +-2.5 V (or less with internal gain).The circuit as shown may not be suitable to direcly drive the ADC input. The ADC input should be diven with much lower impedance, more like in the 100 Ohms range than the 100 K range.

author: MasterT
author_rank: Frequent Contributor
timestamp: July 28, 2022, 09:25:08 pm
content: Page 85 figure 7-1 Application Example.ADC doesn't have input buffer, impedance is 260 kOhm at G=1, 102k resistor is no go. Again, look for examples.

author: Terry Bites
author_rank: Super Contributor
timestamp: July 28, 2022, 11:48:10 pm
content: Use a good free pd amp design tool. Then an SE to Diff converter circuit - read:www.analog.com/en/design-center/reference-designs/circuits-from-the-lab/cn0272.htmlThe differntial photodiode amp has a single bias point for both cathodes, the anodes are a zero volts. Easy.

author: Chris42
author_rank: Contributor
timestamp: July 29, 2022, 07:35:18 am
content: Quote from: MasterT on July 28, 2022, 09:25:08 pmThat's a good point!I have updated the circuit (gain was also to low) and now this resistor is 750 ohms.Quote from: Terry Bites on July 28, 2022, 11:48:10 pmThis circuit would be good however it would be nice to get away with just a single rail supply. This circuit is going to be powered from micro USB port so I would need a switching converter to get +-5V rails.
PSPICE help - Page 1
Forum section: electronics / beginners

author: slow_rider
author_rank: Regular Contributor
timestamp: February 27, 2015, 01:22:11 pm
content: I have defined a voltage controlled variable impedance and would like to use the control voltage in order to change the resistances and see the output for all the different values. From whatever reason it will only show me one in TRAN. Any suggestions?Vscr 1 0 PULSE (0 1 0.5m 1u 1u 0.5m 1)Vcontrol 4 0 DC 1L 1 2 10mC 2 3 1uRref 5 0 50X 4 0 5 3 0 ZX <-- ctrl+ / ctrl- / Rref / out+ / out-.LIB C:\CIR\CADLAB.LIB.TRAN 0.1m 4m 0 10u.DC Vcontrol LIST 0.5 1 1.5 2.PROBE.ENDSo this is basically Vscr going into L - C and R(Vcontrol)
PSpice - Resistor Tolerance - Page 1
Forum section: electronics / beginners

author: thebatosai
author_rank: Newbie
timestamp: February 09, 2015, 04:31:32 pm
content: Hi,I am learning to use PSpice and I stumbled upon fairly simple problem but unable to figure out. I want to add PSpice - Resistor Tolerances to the resistor but for some reason tolerance field is disabled. I am using generic resistor from analog library. Any suggestion, if I am not understanding something here.
PSpice simulation of LM4871 oscillator - Page 1
Forum section: electronics / beginners

author: judge
author_rank: Contributor
timestamp: May 12, 2021, 05:21:19 pm
content: I'm trying to run a simulation of the circuit below (using a LM4871 model) in PSpice (the TI version) but it doesn't oscillate. Could this be because of how I set up the run parameters, or am I just expecting too much from the LM4871 model?

author: SilverSolder
author_rank: Super Contributor
timestamp: May 12, 2021, 07:10:06 pm
content: Lots of people on here use LTspice, if you don't care about the kind of simulator, you might get more help with that just from more people using it.

author: judge
author_rank: Contributor
timestamp: May 12, 2021, 08:59:28 pm
content: The pspice LM4871 model doesn't work in LTSpice

author: Zero999
author_rank: Super Contributor
timestamp: May 13, 2021, 10:05:00 am
content: I'm confused. I Googled the data sheet for the LM4871 and it's an audio amplifier, not a VFD driver IC, like the LM9022 in the schematic at the start of the thread, but the internals and specification appears to be the same. Are they both the same IC, just with different part numbers, aimed at different applications?

author: Warhawk
author_rank: Frequent Contributor
timestamp: May 13, 2021, 10:22:32 am
content: i would try:"Skip initial bias point calculation" settingsAdd initial conditions - it is IC directive I think. Put there like 0.1V on one cap or experiment..

author: mikerj
author_rank: Super Contributor
timestamp: May 13, 2021, 10:26:49 am
content: Quote from: Zero999 on May 13, 2021, 10:05:00 amYes, the same part with the power of "marketing" applied.

author: judge
author_rank: Contributor
timestamp: May 14, 2021, 12:07:49 pm
content: I used the internal block diagram in the datasheet to model the device in LTSpice. I used the UniversalOpamp2 model and set the level to 3b.