hybridfree/eevblog-posts huggingface dataset:
CAN bus wiring - Page 1
Forum section: electronics / projects

author: Red_Micro
author_rank: Regular Contributor
timestamp: June 26, 2021, 09:25:55 pm
content: In building a small low power CAN network (~1m, ~10 nodes) I'm thinking of how the wiring can be. It has to have four wires (CANH, CANL, Power and GND). The "master" node will power the rest of the nodes. In the attachment there's a high level block diagram and several random wiring ideas. There can be two options: a daisy-chained architecture or a central hub. Given that I have four wires maybe a hub would be more compact, but the daisy chain could give more flexibility depending on the location of the nodes. The IDC one looks good, maybe it can be modified with an smaller connector and twisted ribbon cable. The drawback is that flat ribbon takes more space. So I basically brainstorming right now. Any ideas or suggestions?

author: ChristofferB
author_rank: Frequent Contributor
timestamp: June 27, 2021, 11:29:07 am
content: Ribbon cable and IDC or DSUB9 connectors would be ideal, in my opinion, as you could add devices into the cable by just crimping on a new connector

author: greasemonkey
author_rank: Contributor
timestamp: June 27, 2021, 01:09:14 pm
content: If you want to do it properly you need to daisy-chain it and terminate. The standard CAN bus cable impedance is 120Ohm but it is expensive and hard to work with. You may use UTP or STP cable but you need to terminate it with 100Ohm resistors. It will work just as well and you have enough spare wires for power.Ribbon cable and a central hub topology will probably work too but you may have problems at higher baud rates and would be susceptible to EMI.I would do it properly.

author: dietert1
author_rank: Super Contributor
timestamp: June 27, 2021, 02:13:47 pm
content: On the hardware level CAN is simple and easy to use. USB cable with DSUB9 connectors works well. I think the bus should have no other connectors than those for the nodes. And the bus should include its terminators, so you don't have to think over the terminators again when connecting a node. The terminator fits into the plug.I remember making a bus with 1 m segments from node to node and with 12V as supply to feed analog circuitry in the nodes.Regards, Dieter

author: Siwastaja
author_rank: Super Contributor
timestamp: June 27, 2021, 03:10:32 pm
content: Daisy chain or short (some 5-10 inches max) stubs work, use whichever is more handy. Do note that daisy chaining is a special case of stubs, just with a smaller stub length down to a few millimeters on a well laid out PCB.
Can CMOS and NMOS live on the same front-side bus? - Page 1
Forum section: electronics / projects

author: technix
author_rank: Super Contributor
timestamp: May 09, 2017, 10:11:09 am
content: I finally found myself two D8087 NMOS FPU to go with my 80C88 processor. It is very hard to find the elusive CMOS variant of 8087 (I know that 80C287 are fairly common but those required a 16-bit bus, which my 80C88 certainly don't have.)Can I let them live on the same bus?

author: DJohn
author_rank: Regular Contributor
timestamp: May 09, 2017, 10:31:22 am
content: Probably, although it would be best to check the datasheets of the particular chips that you have, and there's a chance I've overlooked something.The usual problem with interfacing NMOS with CMOS is that NMOS's outputs aren't guaranteed to go above 2.4V, and CMOS usually likes a bit more. But the random 80C88 datasheet I just checked says VIH minimum is 2.2V, so it looks like they've given it TTL compatible inputs. It should be OK.

author: technix
author_rank: Super Contributor
timestamp: May 09, 2017, 11:17:54 am
content: Quote from: DJohn on May 09, 2017, 10:31:22 amWhat if the specific 80C88 (or other members of the bus for that matter, especially my two AS7C4096 SRAM chips and the EPM7128S bus matrix chip) does not support TTL levels?

author: BrianHG
author_rank: Super Contributor
timestamp: May 09, 2017, 11:54:10 am
content: Pullup resistors on the buss & controls would bridge that little extra. It's not as if you need to worry about signals in the 100s of MHz. I would use SIP resistor packs on sip sockets so you may adjust the value if needed, but, you need so little a boost, I would say 1k or 470ohm would give you a clean reliable clearance. Go for the higher resistance, 1k if it works, to prevent excess current consumption unless you really need the 470 ohm pull. Reserve the 470 ohm for open-collector/open-drain outputs only if truly needed.
can estimate the ic number - Page 1
Forum section: electronics / projects

author: zezo2030
author_rank: Contributor
timestamp: June 11, 2025, 12:45:33 am
content: hican estimate the ic number ,,its for small wireless charger and the freq is 140khz .

author: Poroit
author_rank: Frequent Contributor
timestamp: June 12, 2025, 04:00:50 am
content: A photo of the device may help draw some responses.
Can I activate a device using a digital IO pin? - Page 1
Forum section: electronics / projects

author: STMartin
author_rank: Contributor
timestamp: June 19, 2017, 05:35:23 pm
content: I have a DAQ with a number of digital IOs. I also have a device I want to activate with one of these digital outputs. I'm not trying to power it directly, but rather I want to use the device's remote input pin. Ordinarily the device has 5V on the input pin, and connecting it to the device's ground (using a relay or a switch, for example) will activate it. Both the DAQ and device use 5V, and the 100uA of current the input pin passes is well within the DAQs 2.5 mA limit. Can I join the grounds of the DAQ and the device, and drive the input pin directly through the digital output? Or would I be better off using the digital output to switch a transistor to drive a relay?

author: Fungus
author_rank: Super Contributor
timestamp: June 19, 2017, 05:42:32 pm
content: Quote from: STMartin on June 19, 2017, 05:35:23 pmYes.

author: mdszy
author_rank: Unknown
timestamp: June 19, 2017, 07:30:09 pm
content: Yes, a digital IO pin is absolutely perfect for what you're doing.
Can I connect these two grounds together? (famous last words) - Page 1
Forum section: electronics / projects

author: opusensemble
author_rank: Contributor
timestamp: October 13, 2015, 01:56:44 pm
content: I have floating a HV circuit (transformer 2200V AC secondary) and a floating LV circuit (transformer 24V AC secondary), for which I would like to connect their floating grounds GND1 and GND2 together (image attached). Can this be done without defying any basic rule in physics or electronics?If you're asking why I need this:The LV circuit will supply an opto-isolated IC (with 4kVpeak isolation) which allows voltage measurement through a resistor voltage divider in the floating HV circuit. A common ground is thus required.

author: Fungus
author_rank: Super Contributor
timestamp: October 13, 2015, 02:00:41 pm
content: Yes.(And thanks for such an amazingly clear, informative, well presented question)

author: NEYi
author_rank: Contributor
timestamp: October 13, 2015, 02:13:50 pm
content: You can always measure the voltage difference between two grounds.If there's like 310V difference – I'm pretty sure it's obvious that connecting them won't lead to anything productive.

author: opusensemble
author_rank: Contributor
timestamp: October 13, 2015, 02:41:14 pm
content: Thank you for confirming Fungus. Thank you too Neyi, Blueskull.

author: Marco
author_rank: Super Contributor
timestamp: October 13, 2015, 03:44:33 pm
content: If the positive output of your HV transformer for some reason gets grounded your 24 transformer will see high voltage across it's isolation, might as well get one which is hipot tested at =>2.5kv.

author: Nerull
author_rank: Frequent Contributor
timestamp: October 13, 2015, 04:06:25 pm
content: Quote from: NEYi on October 13, 2015, 02:13:50 pmCapacitive coupling could produce large voltage differences, so that's only reliable if you do a low impedance measurement.
Can I create a constant current supply using a few TLC5940's?  - Page 1
Forum section: electronics / projects

author: TECH_GEEK10
author_rank: Contributor
timestamp: April 03, 2015, 04:27:43 pm
content: I urgently need a constant current, (cc) supply for the purpose of charging a 10 cell, 16Ah Li-Ion pack. I will be charging one cell at a time. I have 50+ PTH Texas Instruments "TLC5940NT"'s that I think I might be able to use for this setup, as they provide a constant current output. I believe I can create a constant current PSU if the PWM out is set to 100%, or so that it doesn't pulse low anymore, & connected all the outputs together for increased current output.Would I be able to use that setup as a constant current power supply? I don't need it to supply much current. The maximum current I would need is ~5A at ~4.2V, which would likely need to use multiple TLC5940NT's to achieve that rating. Right?DatasheetThanks for your help...Stephen

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 03, 2015, 04:53:00 pm
content: Terrible idea. Buy a charger, you're messing with batteries that can explode in extreme cases, and lithium batteries need more TLC than other chemistries.http://batteryuniversity.com/learn/article/lithium_based_batteriesHow urgent is urgent? There might be a hobby shop in your area that sells chargers. A LiPo charger should support Li-ion. Or buy a IMAX B6 on ebay.

author: TECH_GEEK10
author_rank: Contributor
timestamp: April 03, 2015, 04:58:57 pm
content: Quote from: Alex Eisenhut on April 03, 2015, 04:53:00 pmI would be charging them well under their max voltage. (4.0V) The pack also has a battery protection circuit built in that protects each cell from under voltage, over voltage & over current. I don't think the way I would be doing it presents any more risk than using a imax b6 or equivalent.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 03, 2015, 05:15:15 pm
content: Then why even ask? Go ahead.Do you even know how the protection circuit works? By blowing a fuse. You'll never use that battery again.What power supply were you planning on using anyways?
Can I do harmonic analysis of my mains with a sound card? - Page 1
Forum section: electronics / projects

author: Alexandre Mello
author_rank: Newbie
timestamp: November 13, 2013, 06:51:50 pm
content: Can I do harmonic analysis of my mains with a sound card? How do I make an attenuator to match the input requirements of it?I already have a software to do this analysis. What I don't have is an attenuator that makes this operation safe to me and my sound card, and does not interfere in the measurement.Here where I live, the mains voltage is 127V, and I'm thinking in an attenuation of 100x, then my signal at the input at the interface will be 1,27V.Anyone can help?

author: turbo!
author_rank: Regular Contributor
timestamp: November 13, 2013, 09:34:05 pm
content: Quote from: Alexandre Mello on November 13, 2013, 06:51:50 pmYou can fine tune the final reduction with resistive dividers, but you'll need a transformer with good frequency characteristics up to the n-th harmonic you need for galvanic isiolation. Perhaps an output transformer for vacuum tube amplifier?

author: Stove
author_rank: Contributor
timestamp: November 14, 2013, 08:26:12 pm
content: Don't use transformers, if they are too small and saturated they willeven on no draw. Use a resistor divider and then an optical isolator. Be sure to separate power supplies, no much point in isolation otherwise. Upload results please.
Can I drive Peltier Cooler Modules Using Linear Regulators - Page 1
Forum section: electronics / projects

author: Arsh ahmad
author_rank: Regular Contributor
timestamp: August 10, 2022, 05:40:21 am
content: Hello,I want to design a controller for the Peltier module that needs about 6 Amps at 12 volts, But I also want to change its temperature when I want to. One possible solution I can think of is Design a Regulator which I can power with a 6A supply of 12 volts and then I can adjust the output voltage of the Linear Regulator in this way I can control the power through the TEC.I want to know if it will work or if I need another method.Thank you

author: james_s
author_rank: Super Contributor
timestamp: August 10, 2022, 06:51:09 am
content: Sure it will work, but it's not going to be very efficient. I think a better way is to use PWM, depending on the thermal time constant of your setup the frequency could be quite low. An off the shelf PID controller would probably work.

author: Arsh ahmad
author_rank: Regular Contributor
timestamp: August 10, 2022, 07:04:49 am
content: High Voltage TEC controllers are not available so I need a method to drive them for now I need an Open Loop Control. I need to know how to control TEC current or Voltage through PWM since it will require an efficient filter.

author: Wolfram
author_rank: Frequent Contributor
timestamp: August 10, 2022, 08:35:07 am
content: Direct PWM is not ideal for Peltier elements, as losses are proportional to the RMS current while heat transfer is proportional to average current. A PWM waveform has an unfavorable ratio of average to RMS current (1/sqrt(2) = 0.71 for 50 % duty cycle), reducing the system efficiency. As mentioned, a linear regulator will have significant losses as well. A switching regulator would be my chosen approach, for example a buck converter if the supply voltage is higher than the required maximum voltage of the Peltier element.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: August 10, 2022, 02:23:43 pm
content: Is exact temp control necessary? Or can an old fashioned on/off switch work?If it is an incubator for laboratory purposes the temp range is more exact than if it is just to keep your bananas cool.A bang-bang circuit that turns on the cooling module at its most efficient voltage might be helpful and less wasteful of power especially if the power is a battery.

author: Siwastaja
author_rank: Super Contributor
timestamp: August 10, 2022, 02:39:48 pm
content: You totally can, efficiency is crap, but it's crap anyway with Peltiers. If you manage to successfully cool the Peltier itself, which is not trivial at all, then you no doubt manage to cool the linear regulator which can work with high temperature difference to the atmosphere, unlike the Peltier.With PWM, you risk physically damaging the Peltier. Plus efficiency is crap at <100% duty. Approximately equally crap to the linear regulator solution.Best option is adjustable DC/DC converter.
Can I drive the bias pin on this LED driver directly? - Page 1
Forum section: electronics / projects

author: Starlord
author_rank: Frequent Contributor
timestamp: February 28, 2015, 03:13:20 pm
content: I was looking at this LED driver IC:http://www.diodes.com/datasheets/AL5801.pdfAnd the PWM example shows a FET being used to drive the BIAS pin low when the PWM signal is high. Otherwise, it's pulled up through a resistor to Vcc.So I was wondering... I assume the BIAS pin needs to be pulled up to the same voltage that the LEDs are being driven with. And the reason the microcontroller isn't connected directly to the pin in the example is because you don't want to be trying to drive a pin being fed with 12V from a 5V microcontroller pin.But let's say the LED is being driven from a 5V source. In that case, would it be unwise to PWM the BIAS pin directly, through that resistor?I noticed on this other IC that that seems to be kinda what they've done internally, but they don't have the additional FET inside to handle higher currents:http://www.infineon.com/dgdl?fileId=5546d4624b0b249c014b7d698b0c4636

author: Andy Watson
author_rank: Super Contributor
timestamp: February 28, 2015, 07:36:22 pm
content: No.Quote from: Starlord on February 28, 2015, 03:13:20 pmIt needs to be pulled up to a voltage that is sufficient to turn on the driver mosfet. Datasheet says 4.1V .QuoteYou need to insert some form of current limiter between the microcontroller and the bias input.QuoteTry it. You might find that with only 5V "headroom" that the response is a bit slow. Calculate the bias resistor as if it were working on a 5V source - make sure that the micro can supply sufficient current.
Can I extract video from a LOREX NVR camera thru ENET without a NVR controller? - Page 1
Forum section: electronics / projects

author: zboltman
author_rank: Newbie
timestamp: September 06, 2024, 06:24:42 pm
content: Have a few new LOREX cameras that are over 10 years old.LOREX no longer has compatible NVR controllers / recorders for them. (At least none in stock)Camera is MODEL LNB3143R-C Has a CAT5 and a 12vdc connector.Would like to find a way to Hook this to my computer and extract video from the camera.I've attached a screenshot of the specs. It's greek to me...

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 07, 2024, 04:35:24 am
content: See if you can get it to work with Frigate.
Can I get -5V from an "isolated" DC-DC converter? - Page 1
Forum section: electronics / projects

author: rea5245
author_rank: Frequent Contributor
timestamp: December 28, 2019, 03:58:23 pm
content: Hi. I have a +5V supply and I need to get -5V (low current, a few mA) for one part of my circuit. I'm looking at the PDME1-S5-S5-S DC-DC converter module (https://www.cui.com/product/resource/pdme1-s.pdf) which says it takes a +5V input and produces an isolated +5V output.Am I correct that, since it's isolated, I can tie its +Voutput to my board's ground so that the 0V output is -5V relative to my ground?Is there really a tiny transformer in that module, or is there another strategy for isolating power?Thank you,Bob

author: Siwastaja
author_rank: Super Contributor
timestamp: December 28, 2019, 04:16:16 pm
content: Yes, you can do that, and yes, it has a tiny transformer and a crappy driver driving it.Note they are unregulated and the ripple and EMC may not be that great.

author: daqq
author_rank: Super Contributor
timestamp: December 28, 2019, 09:04:13 pm
content: QuoteYup, it's a tiny transformer. See:Isolated modules are generally more expensive than a non isolated solution and may have various issues (lack of regulation and feedback, minimum load requirements...). Also, that module looks like a massive overkill for a few mA. Maybe you could look at non-isolated solutions such as:https://www.analog.com/en/technical-articles/micropower-sot23-inverting-dcdc-converter-extends-battery-life.html

author: MagicSmoker
author_rank: Super Contributor
timestamp: December 28, 2019, 11:18:19 pm
content: Quote from: Siwastaja on December 28, 2019, 04:16:16 pmWell, whaddya expect for $4?OP: If the output doesn't need to be isolated and the load only draws a few mA then the obvious solution is the classic '7660 inverting charge pump. The original part number is ICL7660 but it has been second sourced by pretty much every semi manufacturer on the planet:https://www.mouser.com/Semiconductors/Power-Management-ICs/Voltage-Regulators-Voltage-Controllers/Switching-Voltage-Regulators/_/N-668jtZ1yzvvqx?Keyword=7660&FS=True

author: mariush
author_rank: Super Contributor
timestamp: December 29, 2019, 12:10:28 am
content: For non isolated output, look up ratiometric / charge pump regulators.Here's examples:https://www.digikey.com/short/zc8r13Microchip makes one in DIP package, TC7660 :http://ww1.microchip.com/downloads/en/DeviceDoc/21465C.pdfIt's cheap and in the list above, for under 1$.

author: rea5245
author_rank: Frequent Contributor
timestamp: December 29, 2019, 12:16:03 am
content: This is a one-off hobby project, so I'm favoring a single-component, easy-to-solder solution.- Bob

author: MagicSmoker
author_rank: Super Contributor
timestamp: December 29, 2019, 12:57:57 pm
content: Quote from: rea5245 on December 29, 2019, 12:16:03 amCheck out Recom part number RFM-0505S - 5V in to 5V out at 1W for $1.41 in single quantities at Mouser.
Can I improve the range on the component tester of my analog oscilloscope? - Page 1
Forum section: electronics / projects

author: nmoore
author_rank: Newbie
timestamp: September 02, 2023, 06:05:06 pm
content: I have an analog oscilloscope with a component tester. It works fine except the range value for capacitors is only good between 0.1uF to 220uF. Is there a way improve this on the oscilloscope or to make an added circuit so that I don't see a vertical line for capacitors greater than 220uF?I have attached pictures (2.2uF, 220uF, 0.1uF in order) to hopefully add clarity. Any assistance or insight is greatly appreciated.Oscilloscope: Heath 4552 25MHz

author: kripton2035
author_rank: Super Contributor
timestamp: September 02, 2023, 06:47:44 pm
content: nopebuy a cheap transistor-capacitor-everything tester there are plenty on the bay or alithey will give you far more accurate values for your capacitors and they are less than $20example:https://www.aliexpress.com/item/1005005237453489.html
Can I increase the current in this power bank? - Page 1
Forum section: electronics / projects

author: Logan
author_rank: Frequent Contributor
timestamp: October 31, 2021, 03:30:11 pm
content: Hi friends.The picture is the PCB of a Philips power bank. There are only 2 chips. The 2 USB output are connected to the same line, and limited to 5V/2A.I want to raise the over-current protection point a little, like 2.5A. I assume I can just change a resistor to alter the factory setting. But I cannot find the chip model, so I don't know how to do it without the PDF for the chip.Any ideas?Thanks.

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 31, 2021, 10:59:01 pm
content: Follow that connection.It seems to use the coil resistance as shunt but not sure.Check the voltage there with and without load.

author: Terry Bites
author_rank: Super Contributor
timestamp: November 02, 2021, 01:42:52 pm
content: It looks like monlitthic power device part numberwww.monolithicpower.com/en/There are usuall two ways of setting a current limit- Rsense or some threshold pin conected to a voltage divider. Draw out the schematic. The current limit probably protects a pass element. So cautiously reduce Rsense in small steps and check for overheating. A 25% increase in Ilim doesn't seem like a crazy idea.

author: Logan
author_rank: Frequent Contributor
timestamp: November 02, 2021, 04:41:32 pm
content: Quote from: DavidAlfa on October 31, 2021, 10:59:01 pmI just checked the voltage across the capacitor you marked, it's the same as battery voltage, regradless of thr load.
Can I leave ncp59150 error flag floating? - Page 1
Forum section: electronics / projects

author: Paroidia
author_rank: Contributor
timestamp: March 14, 2024, 05:00:08 am
content: Datasheet is unclear if the error flag pin can juts be left floating if not needed. It seems like it should but the datasheet says nothing about this.https://www.onsemi.com/pdf/datasheet/ncp59150-d.pdfAlso it states that when the LDO is disabled it doesn't need an external diode to prevent reverse current flow from e.g a backup battery, however in my application 5v from USB will sometimes be connected to the Vout from the regulator while Vin is still connected and I assume in that case an OR-ing diode is still needed.

author: PCB.Wiz
author_rank: Super Contributor
timestamp: March 14, 2024, 07:53:31 am
content: Quote from: Paroidia on March 14, 2024, 05:00:08 amIt's open drain output only, so you can leave it not connected.Quote from: Paroidia on March 14, 2024, 05:00:08 amIf you do not want your powered regulator trying to power the USB 5V, then yes.

author: Paroidia
author_rank: Contributor
timestamp: March 15, 2024, 02:59:56 am
content: Thanks.
Can I make something useful with this? - Page 1
Forum section: electronics / projects

author: Cicada
author_rank: Regular Contributor
timestamp: August 02, 2023, 09:28:51 pm
content: Hello,I bought reels of components at an auction. I have already re-sold much of the original purchase to international respectable component distributors. However, I still have some stock left, and I intend to discard most of it. Before doing so, I have a couple of questions.1. Are there any other uses for crystals other than implementing a clock source for a microprocessor or similar devices?2. Could one use the crystals together with some of the other items listed, such as switch mode regulators, Piezo buzzers, SMD speakers, transistors, FETs, logic, capacitors, diodes, and inductors, to build something useful? If so, please mention a couple of ideas for the crystals, as I am considering reducing my stock of them first.3. What else can I build using this list of components? I am willing to procure extra components to build a project from the components that I have. I have been thinking along the lines of an Arduino shield, for example, a high voltage generator like Cockcroft-Walton voltage generators. I am not sure if this would be useful or popular unless you want to build an Arduino power bug zapper.Although high voltage generators are not altogether useless for other applications. I do have 1nF, 2000V capacitors. See AG26,Let's see what ideas come to the fore.Thank you for your ideas and comments.Cicada.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 02, 2023, 10:07:47 pm
content: *Shrug*, crystals are frequency-dependent devices -- filters. You could make a radio IF filter or something, I suppose?Crystals tend to be magnificently useful at the two things they do (oscillator and filter, which are really the same thing, filtering, one with feedback applied), and useless otherwise.Nothing more than general purpose BJTs, and logic/power MOSFETs (I kinda count 2N7002s as "power" because they're slow, in contrast to (very) small and RF types, or they're also regularly used for basic switching/logic function), so you're not going to be making anything dramatic, but you could still cover the HF band, for example.Likewise diodes, being mostly power or zener, except the LL4148s. BAT64-04 also usable as detector/mixer up to, say, VHF? And perhaps some of the rectifiers could be used as varactor.Not really any counter logic, so no PLL tuning, except maybe if you can cook up something with one of the MCUs.Will need inductors for tuning and filtering, and a greater selection of small value capacitors, probably a few variable types.Huh, managed to completely unload the resistors (or never had any(!))? Will need some of those of course.Tim

author: liaifat85
author_rank: Regular Contributor
timestamp: August 06, 2023, 08:01:58 am
content: Crystals are also needed for RTC modules.
Can I manually add "new device support" to PicKit3 via configuration files? - Page 1
Forum section: electronics / projects

author: 741
author_rank: Frequent Contributor
timestamp: March 31, 2024, 09:23:02 am
content: Just wondering whether this is ultimately feasible or if I have to buy a PicKit 5 in order to debug newer devices from MPLAB X.I have the Pickit 3, but this does not support new devices:https://microchip.my.site.com/s/article/Is-my-device-supported-by-the-programmer-debugger

author: jpanhalt
author_rank: Super Contributor
timestamp: March 31, 2024, 10:42:21 am
content: I am not sure that is possible without changing the development toolchain. Here are links from my files. They deal mostly with PK2 and may no longer apply:https://www.eevblog.com/forum/microcontrollers/pickit-2plus/?topicseenhttps://www.electro-tech-online.com/threads/new-life-for-pickit-3-stand-alone-programmer-app.163164/https://www.pickitplus.co.uk/Typesetter/

author: coromonadalix
author_rank: Super Contributor
timestamp: March 31, 2024, 02:28:45 pm
content: buy the pickitplus software and be happy if your mcu is supported ... i didnot sure they will ad pk 4 or 5 in their softwarealas things come to an end and the big fellas for sure want you to buy expensive tools, or buy an universal programmer like elnec or xeltec ... $$$ or TNM7000
can i mod a power supply - Page 1
Forum section: electronics / projects

author: Arcamax
author_rank: Regular Contributor
timestamp: May 12, 2015, 05:25:50 pm
content: can i take this power supplyhttp://www.princessauto.com/en/detail/90w-universal-a-c-laptop-charger-power-supply/A-p8607269eand change the output voltage to 12v and keeping output current at 4.73amps.(i talked to princess about the current and they told me it was)

author: madires
author_rank: Super Contributor
timestamp: May 12, 2015, 05:32:17 pm
content: Can't say very much without a look at the circuit diagram but I guess yes. Maybe it's a simple design with a TL431 driven feedback.

author: Arcamax
author_rank: Regular Contributor
timestamp: May 12, 2015, 05:42:02 pm
content: yeah i just didn't want to buy it first without knowing if it was possible.

author: Isad
author_rank: Frequent Contributor
timestamp: May 12, 2015, 05:42:35 pm
content: Usally laptop charger can be moded easly as madires said they have a feedback loopwich u can change the resistenc but dont know much about that.As if u go to low thepsu shuts down and i dont know whats the min voltage on that thing.

author: rickselectricalprojects
author_rank: Regular Contributor
timestamp: May 16, 2015, 11:15:42 am
content: just get a step down module of ebayhttp://www.ebay.com.au/itm/DC-DC-CC-CV-Buck-Converter-Step-down-Power-Supply-Module-7-32V-to-0-8-28V-12A-GA-/181617142420?pt=LH_DefaultDomain_15&hash=item2a4939aa94that one is rated for 12a and you would have a much wider range of voltage and you could even use that charger as a bench power supply with that module. (that's what i did when i was starting out)hope this helps
Can I omit transformer in LAN switch for internal connections? - Page 1
Forum section: electronics / projects

author: rkosegi
author_rank: Newbie
timestamp: January 10, 2022, 11:23:34 am
content: Suppose I want to connect several devices (Raspberry PI for example) using LAN switch (eg. RTL8309) within same system. All devices will share common GND and Vcc with LAN switch circuit.Can I omit transformers on data lines between devices and LAN switch? Will it then need some discrete components?

author: wraper
author_rank: Unknown
timestamp: January 10, 2022, 11:25:21 am
content: https://www.ti.com/lit/an/snla088a/snla088a.pdf

author: rkosegi
author_rank: Newbie
timestamp: January 10, 2022, 12:39:15 pm
content: More then I asked for, thank you
can i read and write data to mass storage flash drive by lpc1768 itself alone? - Page 1
Forum section: electronics / projects

author: navidrct
author_rank: Regular Contributor
timestamp: August 06, 2017, 08:06:44 am
content: hii want use lpc1768 to read and write to usb mass storage deviceshould i use this Fig30?or this Fig29?for reading and writing to USB MASS STORAGE DEVICE?I'm asking about hardware design of it
Can i remove the usb series resistor if the mCU is connected to a usb hub IC? - Page 1
Forum section: electronics / projects

author: drakejest
author_rank: Regular Contributor
timestamp: June 27, 2023, 02:12:51 am
content: Im trying to reduce the number of components my board have to make it more compact without reducing the component packages. I was wondering if i could remove the usb series resistor because i read that it is for the signal integrity when using a usb cable, since my 4 MCU is wired directly to the usb hub IC are these still needed?The usb hub IC im using is theFE1.1Sand the mCus are theRP2040.Im looking at reference designs of other usb hub IC fom texas instruments and i dont see them, but this could just be because they are typically placed on the slave device and not on the hub itself.

author: ataradov
author_rank: Super Contributor
timestamp: June 27, 2023, 02:30:52 am
content: They are less critical when traces are short, so it is likely to work just fine.Whether they are needed or not depends on the specific device, and most devices don't need external termination resistors, as their interface is intrinsically matched.Also, they should not be 10k, but I assume those are placeholders.

author: drakejest
author_rank: Regular Contributor
timestamp: June 27, 2023, 02:48:27 am
content: Quote from: ataradov on June 27, 2023, 02:30:52 amI could still impedance match the traces, if that helps it a bit.Quote from: ataradov on June 27, 2023, 02:30:52 amYes only a placeholder, i forgot to change their values

author: ataradov
author_rank: Super Contributor
timestamp: June 27, 2023, 02:52:11 am
content: Quote from: drakejest on June 27, 2023, 02:48:27 amYou are not going to pull 30 Ohm with just the traces. But don't bother, remove the resistors and you will be fine. USB FS is very tolerant, and with the hub IC you have a known and predictable environment.
can i trust simcom sim800? - Page 1
Forum section: electronics / projects

author: alireza7
author_rank: Regular Contributor
timestamp: February 07, 2018, 04:18:48 pm
content: hii want to use simcom sim800 on a industrial Mass production and my product should pass some environmental experiments likeMecanical shock , Vibration , Magnetic field test , Electostatic discharge , Conducted electromagnetic field , Dry Heat test 70ºC, Cold test -40ºC , ... base on ISO Standard (ISO 4064)is simcom sim800 a right choice?can i trust simcom sim800 for such an application? is it reliable ?

author: picandmix
author_rank: Frequent Contributor
timestamp: February 08, 2018, 09:34:19 am
content: Think this will answer your question.http://www.raviyp.com/embedded/208-don-t-use-sim900-sim908-sim800-sim808-modules-in-usa-2g-sunset

author: stmdude
author_rank: Frequent Contributor
timestamp: February 08, 2018, 05:45:03 pm
content: I'd look into the UBlox modules.I don't know about industrial, but they're ISO 16750 (Road vehicles) and have extended temperature ranges (-30 to +85C typically), so they do seem to know about harsh environments.

author: alireza7
author_rank: Regular Contributor
timestamp: February 09, 2018, 04:48:04 pm
content: yes you are right i should look ahead.what about quectel? have any one worked with this company chip sets? i think UC15 from this company can be a good choice.https://www.quectel.com/product/uc15.htm

author: picandmix
author_rank: Frequent Contributor
timestamp: February 09, 2018, 05:13:02 pm
content: Quote from: alireza7 on February 07, 2018, 04:18:48 pmThink you need to specify your other factors before just picking out a module .Mass production - quantity 500, 1000, 10,000, 100,000, + ?Market Sector - Industrial, Medical, Consumer etc.Do you really want an add on module or to integrate a chip into your existing pcb, which would lower cost on a large scale.You sound like you are in early development, so probably buy one of each of those dev boards just to prove your concept first.Then, if you really do need large quantities you need to look at what devices are used in existing devices and have a proven track record in the field.

author: Phoenix
author_rank: Frequent Contributor
timestamp: February 09, 2018, 10:55:34 pm
content: Sim 800 is quite old. Choosing a module is not to be taken lightly. Don't even think about rolling your own rf solution because I'm sure you don't have a team of rf experts at your disposal.Important to consider: what countries, which networks, LTE and or 3g and or 2g, data rate requirements, range requirements, mobile or fixed, accessible distributors of a brand, compliances (eg fcc, ptcrb, Verizon, atnt in USA), cost, integrated GPS, temperature range etc.Sent from my G8441 using Tapatalk
Can I use 2 scopes with dual trace to see 4 traces? - Page 1
Forum section: electronics / projects

author: Rollin Hand
author_rank: Regular Contributor
timestamp: June 20, 2019, 04:22:45 pm
content: I have 2 tektronix tds 724 .How can I see 4 traces in sync ,how to sync the 2 scopes in sync?

author: oPossum
author_rank: Super Contributor
timestamp: June 20, 2019, 04:30:54 pm
content: Connect trigger out of the first to trigger in of the second. Configure the second for external trigger and the same horizontal timebase settings as the first.

author: bob91343
author_rank: Super Contributor
timestamp: June 20, 2019, 04:48:34 pm
content: You can also put the two external triggers in parallel and trigger externally.Unfortunately unless you are crosseyed you won't be able to look at two screens at once.A simpler way is to get an oscilloscope with four channels. Or obtain (or construct) an electronic switch, a device that once was used to make a single trace unit into a dual trace. You would need two of these.In any case you will have to manipulate the trigger controls to get the desired display.

author: David Hess
author_rank: Super Contributor
timestamp: June 20, 2019, 10:57:01 pm
content: The trigger or vertical output from one oscilloscope can feed the trigger input of the other oscilloscope however it is usually better to just trigger the oscilloscopes off of the same source using their external trigger inputs.Quote from: bob91343 on June 20, 2019, 04:48:34 pmA TDS724 is big enough that one can be stacked on the other. I have actually done this with 2230/2232 oscilloscopes stacked on top of each other and it is actually pretty handy. And as a bonus, the oscilloscopes can still be used independently to make measurements that a single timebase oscilloscope cannot. This duplicates the functionality of some impressive old instruments like the Tektronix 547, 555, 556, and 7000 series which could essentially operate as two independent oscilloscopes with one display.
Can I use a Sealae Logic Analyser on this TV Pattern Generator Circuit? - Page 1
Forum section: electronics / projects

author: Chris56000
author_rank: Frequent Contributor
timestamp: April 13, 2024, 02:26:13 pm
content: Hi!. . .I'm still puzzled with getting operating wave-forms from the Line Sync. Generator of my 1979 Intracept Electronics N7118 Colour TV Pattern Generator - several Members of the UK Vintage Radio Forum have asked about the circuit operation of this device, as they're restoring old ones written off by NiCd battery corrosion, etc., these were originally built from kits and no circuit description is provided in the little documentation that has been found for these!. . .My question is, will one of the cheapie Sealae 16-Channel Logic Analysers tolerate an 8 V peak-to-peak input? I have attached the relevant section of Line-Sync Divider and generator circuitry below I am attempting to describe the operation of, and the whole unit operates off an 8.4 V rechargeable battery!. . .If anyone has any tips for getting all the wave-forms in the correct timing positions, for describing how it works, I would greatly appreciate them!Chris Williams

author: DavidAlfa
author_rank: Super Contributor
timestamp: April 13, 2024, 02:56:23 pm
content: Not directy, but a simple resistir divider will do the job, like 1K/1K, making 4Vpk.Maybe it works fine at 5Vdd?
Can I use 2 pin JST-ZH connector on flex PCB Board having 0.2 mm thickness ? - Page 1
Forum section: electronics / projects

author: Sai teja
author_rank: Regular Contributor
timestamp: October 06, 2018, 04:59:10 am
content: Hello,I am planning to use 2 pin SMD "JST ZH connector" (top entry type) on my flex PCB circuit having thickness 0.2mm. But in the datasheet, it is mentioned that applicable PC Board thickness is 0.6 to 1.2 mm, 1.6 mm.What is the significance of that number?Here is the datasheet of the part :http://www.jst-mfg.com/product/pdf/eng/eZH.pdfRequired Part number for my application : B2B-ZR-SM4-TFPlease help me in this regard.Thanks in advance.

author: Nusa
author_rank: Super Contributor
timestamp: October 06, 2018, 06:08:13 am
content: You're probably fine. Board thickness is more critical with the through-hole configuration. Or the SM2 configuration with mounting pins. Solder pads plus solder pins on the SM4 version will be less robust on a flex board, but should work.

author: jbb
author_rank: Super Contributor
timestamp: October 06, 2018, 08:27:48 am
content: I suggest adding a stiffening layer under the connector. This could be polyimide or FR4 for thicker/stronger.

author: Sai teja
author_rank: Regular Contributor
timestamp: October 06, 2018, 09:35:57 am
content: Thanks Mr Nusa,May I know why SM4 type connectors are less robust for flex?

author: Nusa
author_rank: Super Contributor
timestamp: October 06, 2018, 10:02:50 am
content: Quote from: Sai teja on October 06, 2018, 09:35:57 amA connector attached by 4 inflexible solder joints is sturdier when the board they're attached to is also inflexible, or nearly so.
Can I use one of these cheap solar chargers with a generator? - Page 1
Forum section: electronics / projects

author: mb300sd
author_rank: Contributor
timestamp: April 01, 2015, 08:47:24 pm
content: I'm working on a project where I want to use a DC motor as both a starter and generator on a small engine. I've found these cheap chargers meant for use with solar panels.http://www.ebay.com/itm/Digital-PWM-30A-Solar-Charge-Controller-Regulator-12V-24V-Solar-Panel-USB-DC-/141527564635?pt=LH_DefaultDomain_0&hash=item20f3b3415bDoes anyone see a reason why they wouldn't work for regulating the output voltage of a DC generator? Input is rated at 44V and I will be charging a 24V battery. My motor outputs around 38V open circuit when spun at 3600rpm (engine speed), and is rated 2500RPM@24V. I can add filtering capacitors to smooth input voltage if needed. I can't think of any reason it wouldn't work, but thought I'd ask some experts before I bought one.

author: DanielS
author_rank: Frequent Contributor
timestamp: April 01, 2015, 09:39:12 pm
content: Assuming the thing really does what it says it does and does it properly, I see no reason why it should care what the input actually is as long as the input is within expected specs either.
Can I use stranded stainless steel wire as a receiving antenna? - Page 1
Forum section: electronics / projects

author: Terry Bites
author_rank: Super Contributor
timestamp: May 20, 2024, 12:15:12 pm
content: I've got loads of 1.5mm stranded stainless steel wire and gripples galore (I'm very tense).Could I use this kind of wire to make a receiving antenna for 100k-30M.I suspect that strands rubbing together with a bit of water and grime will generate noise.Will that be an issue or is it just going to be LF nosie?Anyone?

author: CaptDon
author_rank: Super Contributor
timestamp: May 20, 2024, 12:39:52 pm
content: I have not used stainless stranded but have used stranded of other materials and I don't think there was any difference vs. solid conductor. Chances would seem that any noise generated within the wire from physical activity would be at least 30 to 50 dB below local EMI at those frequencies.

author: LaserSteve
author_rank: Super Contributor
timestamp: May 20, 2024, 02:55:30 pm
content: Go for it.Use a good compression splice or braze / silver solder a terminal on for the lead wire. If you braze or solder, make sure the metal is actually wetted by the filler material. So possibly an acid flux is required. I'd be weary of crushable aluminum splices over time.Terminate at both ends if possible. I hate loose strands.An Ohm Meter is your friend here. If you have a good DC connection you'll be fine.With it being multi-stranded, that will help with the skin depth issues. Traditional ham antenna wire is copper flashed steel. The flashing is mainly for connecting, not conducting.You could always use it as a carrier for copper, but I doubt you will need to do that.HF is a bit dead/weak/ wierd these days due to peak solar cycle, so expect higher frequencies then usual to work better during the day, and go down band at night. Check your daily space weather and propogation forcasts before before blaming your antenna.We're getting hammered by Solar Flares. I never expected to see an Aurora in North East Ohio, but we did.Steve

author: jwet
author_rank: Frequent Contributor
timestamp: May 21, 2024, 05:34:49 am
content: Ham's use copper clad iron/stranded steel wire for antenna's all the time. It has a nice combination of strength, good conductivity especially when the copper is fresh and low cost. After a few years, the copper corrodes away mostly and leaves the iron/steel for most of the life of the antenna- the conductivity is marginally lower but in the gran scheme of things- its very good. Stainless is at least as good. Another data point is sailors that use the standing rigging on their boats as an HF antenna. A backstay with insulators and an antenna tuner makes a great antenna. Go for it.
Can I use this cable for my project ? - Page 1
Forum section: electronics / projects

author: Hextejas
author_rank: Frequent Contributor
timestamp: February 20, 2018, 12:51:44 am
content: The project is to test my kit build oscilloscope, a DSO 138.Of course I need some test waves and I am using wave form generator software on my android tablet.Its set at 440hz as I am going to use this equipment in an audio system.So, I need a cable to get from my Android to the scope so I was gonna use this one, the red lead.Will that work correctly ?And now on to the scope settings.I dont know where to start. Normally I just start changing settings until the wave form looks recognizeable.Could you give me what your starting settings would be for the scope ?And many thanks.

author: danadak
author_rank: Super Contributor
timestamp: February 20, 2018, 01:29:39 am
content: Set DSO138 for -1 mS/div sweep rate1V/div verticalAuto sweep modeVertical mode ACTrigger 0VRegards, Dana.
Can I use this transformer with one them T12 solder control kits? - Page 1
Forum section: electronics / projects

author: shanezampire
author_rank: Contributor
timestamp: July 02, 2019, 07:46:32 pm
content: I have an old OK Industries station that's missing the 6 din pin handle. They are hard to find, obsolete, and cost more than an entire newer station. I tried to retro fit a newer HAKKO FX-888 6 pin din handle (which really only uses 5 pins) and that failed. The OK Industries has 6 pin and uses 6 wires. One with 16v AC and another with 33v AC. Both will heat the iron just fine and you can measure the resistance with a multi-meter going up as it heats up but appears the controller will not control the temp. Its all or none. Plus I ain't even sure I am hooking it up right. Or controller broke? I gave up. Not smart enough to figure it out.Anyways, I was wondering if it was possible to just hook a bridge rectifier to one the 16v AC lines to cut it down to 15v DC and use one them T12 kit/handles in it. The T12 controller should fit in the case just fine. (vertical / sideways) but a simple install where the original controller was at.Can I / do I just go straight from the bridge rectifier to the T12 power in? Do I need anything else added? The transformer says 14v 80VA is that enough power? too much?More pictures of entire thing -https://imgur.com/a/ixcBOFuAnd I tried to make the original controller work -https://www.eevblog.com/forum/beginners/help-with-an-ok-industries-iron-wiring-please/

author: floobydust
author_rank: Super Contributor
timestamp: July 04, 2019, 02:43:49 am
content: The OKI SA-1000 power transformer A41-80-28A33 is made by Pulse 28VCT 2.8A or 14VAC 5.6A 80VA.I would expect 22-19VDC after a fullwave CT (2-diode) rectifier and filter cap. You are getting more than spec because there is no load on the transformer and your mains voltage may be high.T12 clone controllers input is 24VDC 3A peak. There is a 30V limit - the MOSFET and sometimes 3.3V regulator is rated for that max. It depends on the version and make. They do fine on 22-19V. So the transformer would work fine, add a rectifier and big filter capacitor 3,300-6,800uF 35-50V to power the T12 controller. T12's suck for a decent stand though.It's possible to draw a schematic of the OKI controller and see if it can be modded to work with a Hakko 938/888 wand.
Can ICE2B365 be replaced with an ICE2A365 - Page 1
Forum section: electronics / projects

author: stojke
author_rank: Regular Contributor
timestamp: December 25, 2018, 07:50:47 am
content: Hello, I have an power supply that got wet and an ICE2B365 component bit the dust.For some reason all I can find in the country are ICE2A365 and they have an 100kHz switching frequency (Fosc) , where ICE2B365 has 67kHz. Everything else seems to be the same.Can an 100kHz part replace an 67kHz part for the circuit still to operate properly?