hybridfree/eevblog-posts huggingface dataset:
1Gbps between PCB to PCB  - Page 1
Forum section: electronics / projects

author: rakeshm55
author_rank: Regular Contributor
timestamp: July 18, 2019, 03:24:59 pm
content: I have 1Gbps Ethernet signal to be routed to front panel board (PCB). I have limited space available to accommodate RJ45 Jacks (2 jacks one at front panel board and other on a digital board) and cable bends also not sure whether RJ45 jack+RJ45 plug assembly would sustain vehicle mount vibrations.Is there any solution available to route 1Gbps Ethernet from one board to another via a low profile connector.??

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 18, 2019, 03:29:05 pm
content: https://www.harting.com/US/en/solutions/harting-ix-industrial%C2%AE-ethernet-interface

author: IDEngineer
author_rank: Super Contributor
timestamp: July 18, 2019, 03:49:36 pm
content: Interesting that Harting oriented that connector vertically. Every photo shows vertical orientation. I'm sure there's an application somewhere that would rather have a vertical connector, but I can't come up with one right now unless PCB real estate is the limiting factor. I wonder if they offer a more traditional horizontal configuration like USB, HDMI, SATA....

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 18, 2019, 04:14:56 pm
content: Yeah. They have other product lines though, so maybe there's something horizontal as well.The only reason I see is that this same connector put horizontally would not reduce PCB footprint enough compared to an RJ45 connector to really justify it or at least be competitive... as to robustness, it's supposed to have been tested in harsh conditions. Don't know how robust they really are.

author: IDEngineer
author_rank: Super Contributor
timestamp: July 18, 2019, 05:06:39 pm
content: Another argument for the horizontal orientation is strength. Since this connector will be subjected to push/pull cable forces, distributing those forces over a larger PCB footprint would be advantageous. I suppose they could strain relief the connector to a panel, but the photos I saw don't seem to incorporate that option.I'm not dissing the vertical orientation, just saying it's often suboptimal for multiple reasons. I use vertical connectors only when demanded by some outside requirement, otherwise horizontal are generally better.

author: TimCambridge
author_rank: Regular Contributor
timestamp: July 19, 2019, 12:44:20 am
content: Samtec have solutions.https://www.samtec.com/

author: David Hess
author_rank: Super Contributor
timestamp: July 19, 2019, 03:23:05 pm
content: Any connector and cable solution which maintains the impedance expected by the Ethernet transceivers will work; RJ-45 connectors (actually 8P8C modular connector) are not particularly outstanding in this regard. With some care you could get away with ribbon cable and IDC connectors or even 0.1" pin headers.

author: NiHaoMike
author_rank: Super Contributor
timestamp: July 19, 2019, 03:43:51 pm
content: Ethernet is pretty forgiving of signal degradation. In fact, even really poor wiring will tend to work fine until you start to get close to the maximum cable length limit.
1mA precision current source circuit  - Page 1
Forum section: electronics / projects

author: andybarrett1
author_rank: Regular Contributor
timestamp: September 06, 2015, 05:32:27 pm
content: HiLooking for a easy way of getting a 1mA source.... So Ideas welcome...It is for field calibrations by techs that loose things.... They ARE not loosing another Fluke 715 'Ideally needs to operate from a single 9v battery, 0.1% accuracy.Sure it can be done with op-amp but would have thought a single 8pin chip would do it nowadays?Looking forward to hearing / seeing some ideasTYAndy

author: ralphd
author_rank: Frequent Contributor
timestamp: September 06, 2015, 05:42:19 pm
content: Use a .05% accurate meter to hand-pick a tl431 and 2.5K resistor that are within your .1% accuracy requirement. With a small piece of protoboard and a 9v battery clip, your total cost is still under 50c.

author: andybarrett1
author_rank: Regular Contributor
timestamp: September 06, 2015, 06:14:45 pm
content: Quote from: Christopher on September 06, 2015, 05:35:05 pmI saw this but the REF102 Needs at least 11.4V SupplyI need to use a 9v PP3BR Andy

author: Christopher
author_rank: Frequent Contributor
timestamp: September 06, 2015, 07:58:31 pm
content: The 10v ref just makes the calcs easier. A boost converter won't be the most ideal solution because of noise but is certainly possibleHow about a 1v reference and a different sized resistor?

author: eas
author_rank: Frequent Contributor
timestamp: September 06, 2015, 08:21:27 pm
content: Quote from: ralphd on September 06, 2015, 05:42:19 pmIf his time is worth nothing, or he's doing it for fun/learning/etc. Sounds like this is for work though...Here is an idea. Follow ralphs suggestion, or something like it, but make each tech test and select the parts and assemble the source. Perhaps they'll be less likely to loose it if they put some effort into making it?

author: TimFox
author_rank: Super Contributor
timestamp: September 06, 2015, 09:13:02 pm
content: What will you connect the 1 mA source to? If it is a very low resistance, than a simple voltage regulator plus series resistor suffices (adjusting the resistor as required). Otherwise, follow the suggestions above for actual constant-current sources.

author: dom0
author_rank: Super Contributor
timestamp: September 06, 2015, 09:48:02 pm
content: LT3092?At 0.1 % accuracy you will need to trim it, but it's reasonably accurate OOB so the trim adjustment doesn't need to cover a lot of range.

author: andybarrett1
author_rank: Regular Contributor
timestamp: September 08, 2015, 07:38:19 pm
content: Quote from: ralphd on September 06, 2015, 05:42:19 pmHave today ordered up a few bits along these lines to play with..... If this works will be the way forward.Thank you for ALL repliesAppreciatedAndy
1Mhz optical (IR) modulate/deodulate - Page 1
Forum section: electronics / projects

author: max_torque
author_rank: Super Contributor
timestamp: August 01, 2016, 05:48:46 pm
content: Using an typical IR photodiode as a receiver, and an IR LED as transmiter, i'd like to be able to build a reflective "trigger" with a relatively fast response time (say ~5uS).To make the system robust to ambient IR levels, if i modulate the TX at 1Mhz, with a 50% duty, whats the best way of de-modulating the RX signal to maximise the signal to noise ratio. Obviously, the RX signal can be "gated" with the TX signal as both parts of the device are local to each other. (ie, i know when we should be getting back a reflected signal, should the reflective target be in range)Options see to be to AC couple the RX signal or to low pass filter it to make a DC reference level, but there will be trade off's between rejection and response?(the system needs to spot a reflective target passing the TX/RX window at high speed and quickly send out a single pulse to say "target present"

author: Marco
author_rank: Super Contributor
timestamp: August 02, 2016, 03:26:35 am
content: I'd trythis circuitfrom Analog (although obviously it doesn't really need to use their SPDT switch and opamp). The RC filter should have a -3dB of a couple 100 kHz and then you just do threshold detection.

author: max_torque
author_rank: Super Contributor
timestamp: August 02, 2016, 11:47:21 am
content: wow, great replies thanks! I've got a lot to go and readup on now!!Anyone have experience what the upper limit for modulating an IR LED is in terms of frequency? Response times seem to be in the low single nS region according to datasheets, but i wonder what the practical limit actually is. The higher the modulation frequency, the more cycles there will be in my 5uS max detection delay period, so the more robust that detection could be?

author: Kleinstein
author_rank: Super Contributor
timestamp: August 02, 2016, 12:27:15 pm
content: The photodiodes are quite fast, but the very sensitive detection circuits (TIA) are usually not. So it needs some care to make the circuit fast and sensitive. So think more of a transistor in base of gate circuit, than TIA with an OP.Some IR LEDs might already reach there limit at around 1 MHz. Usually the 880 nm LEDs are faster than the 950 nm ones. You can approximately test the speed of the LEDs by looking at there reverse recovery performance. For a 1 MHz modulation, reverse recovery should not take much more than 200 ns, preferably less than 100 ns.Slightly more than 1 MHz modulation frequency might help for a fast response, but it's not useful to go that much higher.It might be worth looking at the background - with enough intensity you might not need true modulation, but just a lower frequency background compensation might be good enough.
1mm banana plugs? - Page 1
Forum section: electronics / projects

author: xaxaxa
author_rank: Regular Contributor
timestamp: January 25, 2018, 04:55:38 am
content: Are there any test probes that can plug directly into 1mm diameter vias on a pcb? I'm doing a small PCBA run and need a way for the manufacturer to program and test each board, but don't want to have pin headers soldered onto the board (too high profile; 90 degree pin headers won't do either because it will obstruct other things on the board).I have already searched aliexpress/taobao for 1mm banana plugs and there are no results; maybe there is another term for it that i don't know?

author: loganrf
author_rank: Newbie
timestamp: January 25, 2018, 05:03:26 am
content: They make some pretty tiny probes that you can use and if your visa are untented you can always use a "bed of nails" type setup. If you've not yet finalized your design then Tag-Connect actually makes some pretty nifty pogo-cables that are perfect for programming boards without needing to solder on a header. They use a special footprint with holes that align the pogo cable with the pads.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: January 25, 2018, 05:19:30 am
content: http://www.tag-connect.com/maybe?

author: janekm
author_rank: Unknown
timestamp: January 25, 2018, 05:36:04 am
content: Quote from: xaxaxa on January 25, 2018, 04:55:38 amDepending on your spacing, this shop makes various headers that can be either pressed on (like tag-connect) or clip on (clothes peg style):https://item.taobao.com/item.htm?spm=a1z10.1-c.w4004-14192554773.7.2ba257b05Ee5ze&id=529323749230(they have 2.54mm, 2mm, and 1.27mm spacing ones). And they can configure them with various types of pogo pin heads (to break through oxidation on pads or vias).They even make a mini-version of the ubiquitous Chinese test jigs:https://item.taobao.com/item.htm?spm=2013.1.20141001.2.3350e0d6wKYUoC&id=43640414794&scm=1007.12144.81309.42296_42296&pvid=2e691d98-7d7a-4cb6-a73e-3e3b6ea97575

author: floobydust
author_rank: Super Contributor
timestamp: January 25, 2018, 06:21:11 am
content: Just use pogo pins
1mm twin core cable - Page 1
Forum section: electronics / projects

author: trevwhite
author_rank: Frequent Contributor
timestamp: February 11, 2014, 10:09:25 am
content: I have been trying to source a 2 core cable that is of 1mm outer diameter - cable size similar to mini headphones. It seems there is a magical machine in the far east that makes this cable specifically and terminates it for headphones. The cable is just not available for anyone else? Does anyone know of a company that supplies reels of such cable?Preference is the UK but I am open to suggestions from anywhere right now.ThanksTrev

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: February 11, 2014, 10:26:44 am
content: 1mm outer diameter is really thin, considering there are 2 cores and insulation. Are you sure that's the correct size?

author: trevwhite
author_rank: Frequent Contributor
timestamp: February 11, 2014, 10:46:16 am
content: yep. 100%

author: EEVblog
author_rank: Unknown
timestamp: February 11, 2014, 11:05:16 am
content: Shielded or unshielded?I do recall using something this small many moons ago but the brand escapes me...

author: trevwhite
author_rank: Frequent Contributor
timestamp: February 11, 2014, 11:10:22 am
content: Well I could handle single core shielded or twin core unshielded at this stage. I think anything would do..

author: EEVblog
author_rank: Unknown
timestamp: February 11, 2014, 11:11:10 am
content: How's this:http://www.daburn.com/specs/2708_Spec_Sheet_11-18-2013.pdf1.32mm OD

author: trevwhite
author_rank: Frequent Contributor
timestamp: February 11, 2014, 11:13:37 am
content: Thanks, might just squeeze in with the OD.
1N5297 equivalent - Page 1
Forum section: electronics / projects

author: Ugur
author_rank: Regular Contributor
timestamp: August 22, 2023, 05:33:51 am
content: Hello,Which diode can I use instead of 1N5297 1mA current limit diode?

author: moffy
author_rank: Super Contributor
timestamp: August 22, 2023, 05:53:22 am
content: These might be possible, but you need to confirm the specs:https://au.mouser.com/datasheet/2/362/P22-23-CRD-1729293.pdf

author: Ugur
author_rank: Regular Contributor
timestamp: August 22, 2023, 07:23:11 am
content: Hello,Thank you for answer.Please excuse I don't know much about this diode.Is it possible to use a diode such as 1N4148 instead of this diode? or if i deactivate this diode and put a jumper there?

author: moffy
author_rank: Super Contributor
timestamp: August 22, 2023, 08:03:15 am
content: The diode is actually a JFET with the gate connected to the source and it acts as a constant current source, above a minimum voltage when reverse biased. So you can't use a normal diode such as the 1N4148 or a jumper.

author: Ugur
author_rank: Regular Contributor
timestamp: August 22, 2023, 08:06:17 am
content: Thank you for the info.

author: Vovk_Z
author_rank: Super Contributor
timestamp: August 22, 2023, 02:17:20 pm
content: Quote from: moffy on August 22, 2023, 08:03:15 am+1, I'm not sure it has an equivalent.

author: TimFox
author_rank: Super Contributor
timestamp: August 22, 2023, 02:40:00 pm
content: If you need a "one-off" component, you can take a JFET withIdss>1 mA and insert a suitable resistor in its source lead, connecting the gate to the other end of the resistor to form a two-terminal component.In that case, you can start with a variable resistor in the obvious measurement circuit and adjust it for 1 mA at, say, 9 V.Then remove the variable resistor, measure its value, and replace it with a fixed resistor.

author: Benta
author_rank: Super Contributor
timestamp: August 22, 2023, 05:08:24 pm
content: J500-series from Vishay/Siliconix. Obsolete, but not too long ago. You should be able to find stock somewhere.

author: Kleinstein
author_rank: Super Contributor
timestamp: August 22, 2023, 06:00:21 pm
content: The original 1N5297 can withstand a relatively high voltage (~100 V). Not many JFETs allow such a high voltage. One could consider using a depl. MOSFET instead, if the high maximum voltage is needed. A BSP135 with a suitable source resistor may do it.

author: moffy
author_rank: Super Contributor
timestamp: August 23, 2023, 12:17:23 am
content: Quote from: Kleinstein on August 22, 2023, 06:00:21 pmThe S-102T and E-102, 1mA/100V Semitec diodes, as previously mentioned in the datasheet reference:https://au.mouser.com/datasheet/2/362/P22-23-CRD-1729293.pdf, appear to be in stock at Mouser

author: Terry Bites
author_rank: Super Contributor
timestamp: August 23, 2023, 10:01:35 am
content: https://www.linearsystems.com/currentregulatingdiodessales@linearsystems.comA Sub $ LM334 It can live with 1V of headroom.Roll your own and tweak it if you darewww.electronicdesign.com/technologies/power/article/21808012/whats-all-this-jfet-constantcurrent-stuff-anyhow
1ps jitter input isolation LVCMOS level - Page 1
Forum section: electronics / projects

author: tchiwam
author_rank: Regular Contributor
timestamp: July 03, 2022, 03:19:34 pm
content: Any suggestions on how to isolate an input, ground and signal, and keep the jitter at bay. Under 1ps ideally under 0.1psI was thinking on taking some 10Gbs Ethernet opto modules..I did find some Renesa opto isolator but the jitter is way above 1ps...

author: m98
author_rank: Frequent Contributor
timestamp: July 03, 2022, 03:30:25 pm
content: Wow, what are you doing that requires a jitter under 0.1ps?

author: tchiwam
author_rank: Regular Contributor
timestamp: July 03, 2022, 03:48:38 pm
content: I am using a timing pulse to sync 4 ADC, right now I found a nice way to get them started all at once and at about the part of the phase.I noticed that I have quite a few ground loop issues and this is what I am trying to solve.The next version will have a low noise DCDC with galvanic isolation. Then an LDO to keep all the power noise to a minimum.Now I am looking galvanic isolation for the timing pulse input. Depending on that performance I'd also want to add it to the some or all outputs.1ps additive jitter ~0.36deg @ 1GHz ... at 3 GHz it is 1deg. I am already at about 50fs additive jitter and <50ps skew output to output...

author: David Hess
author_rank: Super Contributor
timestamp: July 03, 2022, 06:44:31 pm
content: Quote from: tchiwam on July 03, 2022, 03:48:38 pmDifferential signalling for the clock or strobe would be a good place to start. Differential signals are often used for clock and strobe signals for exactly this purpose.QuoteI like the idea of using Ethernet transformers, but are you looking to reduce short term or long term jitter? I think transformers would drift with temperature but that could be compensated for by using an extra and phase locking the output to the input.
1S Li-Ion charger IC with built in LDO - Page 1
Forum section: electronics / projects

author: osannolik
author_rank: Newbie
timestamp: May 03, 2015, 11:06:50 am
content: Hi,I'm looking for a charge + voltage regulator circuit that is capable of charging a 1-cell Lipo at at least 100-300 mA and can be operating with the battery disconnected as well. I really need this to yield a very small total PCB footprint, so I have been looking for charger IC's (SMD) with built in LDO's but only found LTC4063:http://www.linear.com/product/LTC4063Unfortunately, it appears that it can only provide a voltage output while the battery is connected. I want to be able to power my circuit using the source of charging while no battery is connected. I.e. the voltage regulator output should be 3.3 V if the battery is connected or at least if the charge power source is connected. Voltage regulator output does not need to provide more than 30-50 mA.Any tip or suggestion is welcome!

author: Canobi
author_rank: Regular Contributor
timestamp: May 04, 2015, 12:22:38 am
content: Have a look at the MCP73833. Failing that, if your talking about using it while plugged in, you could run the + - rails from the regulated output for the ic to a second terminal point to use when the battery is disconnected.

author: osannolik
author_rank: Newbie
timestamp: May 09, 2015, 09:26:55 am
content: Thanks for the suggestion. The problem with that circuit is, from what I can see, it does not have a built-in LDO with 3.3V output. Indeed I can supply the system without any battery, but if the battery is present, I still need an external LDO.However I found this alternative that appears to solve my problem:LTC3553http://cds.linear.com/docs/en/datasheet/3553fc.pdf3x3 mm QFN with charger, LDO and buck converter. Quite impressive.

author: mikerj
author_rank: Super Contributor
timestamp: May 09, 2015, 11:16:53 am
content: TheSTNS01does pretty much everything you want, apart from having a 3.1v LDO which is a better fit to the characteristics of a lithium ion cell, and most micros etc. these days will happily run at 3.1v.A 3.3v LDO will drop out of regulation before you've used the available energy in the cell.
1st floor lighting wiring update (UK) - Page 1
Forum section: electronics / projects

author: Majorbob
author_rank: Regular Contributor
timestamp: May 04, 2022, 09:31:11 pm
content: Hi All,First off, I'm just designing and specifying at this stage before getting work done further down the line.I'm going to be having a sort of electronics workshop/man cave built in the loft and as part of this am going to fit a small CU for the sockets and Loft lighting circuit so that if anything goes wrong it just trips the loft and not the whole house (House is on RCBOs anyway but if it does trip I don't want to have to climb out of the loft to reset).Now, as part of this I am bringing the 1st floor lighting wiring above the flooring and secured to the rafters so it's all accessible. To increase the ability to modify (and kinda because I can), I want to bring everything back to a central junction box. Does anyone who is very conversant with BS7671 and UK wiring regs know of a reason why I can't repurpose an old 16th edition (2005) CU as a terminal box using standard Weidmuller-type DIN terminals?

author: Monkeh
author_rank: Super Contributor
timestamp: May 04, 2022, 09:35:08 pm
content: Quote from: Majorbob on May 04, 2022, 09:31:11 pmPossible accessibility of live terminals with the lid open?Quote from: Majorbob on May 04, 2022, 09:31:11 pmWhat is your plan for protecting the supply cable?

author: Majorbob
author_rank: Regular Contributor
timestamp: May 04, 2022, 09:48:54 pm
content: Quote from: Monkeh on May 04, 2022, 09:35:08 pmIn the worst case, not without a small screwdriver. If I opt for posher ones with the little push-in latch type connectors, unlikely (depending on how well they fill the MCB-sized gap)... I might nab a couple from work to test this with.Quote from: Monkeh on May 04, 2022, 09:35:08 pmI plan to have a >=40A MCB in the main CU, and use appropriately sized cable (at least 6mm, probably 10mm).

author: themadhippy
author_rank: Super Contributor
timestamp: May 04, 2022, 09:58:39 pm
content: QuoteArguable 536.4.203 ,devices and components that are used in low voltage assemblies (to BS EN 61439) such as consumer units and distribution boards must only be those that have been declared suitable for that purpose by the manufacturer of the assembly.

author: Majorbob
author_rank: Regular Contributor
timestamp: May 05, 2022, 07:01:49 am
content: Short answer is effectively "no" then?
1V to 12+V at low current boost converter. - Page 1
Forum section: electronics / projects

author: xReM1x
author_rank: Regular Contributor
timestamp: September 04, 2015, 03:05:50 pm
content: Hi,I'm looking for a boost converter schematic that doesnt use any IC like LT1073 or any boost converter controller. only simple op amps, transistors, zeners and diode.the input voltage is 1V, the input current is more then 1A and the output current is about 50-30mA, the output voltage can be any voltage above 12V and less then 30V. but it needs to be regulated.I tried looking for schematics on google but after some simulation they where not suitable.

author: xReM1x
author_rank: Regular Contributor
timestamp: September 04, 2015, 07:33:15 pm
content: anyways it turns out I dont need any boost converter.thread closed~
1W multiplier - Page 1
Forum section: electronics / projects

author: Jester
author_rank: Frequent Contributor
timestamp: March 30, 2021, 09:48:24 pm
content: I have and existing circuit board that connects to another uController board with a short ribbon cable and there is only one available data signal being sent from the uC board to the remote board. I need two!This little part looks like it would do the trick, however hand soldering an 8-X2QFN part is more of a PITA than it's worth.https://www.mouser.ca/ProductDetail/Texas-Instruments/TCA5405RUGR?qs=%2Fha2pyFadugl%252BKTTgxvKvobvKNmZFyGCGzlxPFW%2FxGsWHM7EG4GeWA%3D%3DYou would think there would be something like this in a more user friendly package?I can bit bang that one available pin as required.Any ideas or suggestions?

author: penfold
author_rank: Frequent Contributor
timestamp: March 31, 2021, 08:24:10 am
content: ICs such as that, with only a single data line and just a few outputs, may be designed for highly space-constrained environments where the routing of 5 wires from an MCU will take up too much space... so it's likely they will only be made in low area devices packages. If you could stretch to SPI or I2C, then you'll likely find many more options in larger packages, but those devices will be geared more towards functionality and more IO...There are some QFP adapter boards (0.5mm pitch) if its just that it needs to be breadboard-able... but still requires soldering. It's not impossible, but if you've not got a nice sharp soldering iron tip or hot air... still a total PITA - not gonna argue with that!How fast does the interface need to run? If you're going direct to another MCU, then just the TX line of a UART if available... could also bit-bang such an interface but the timing could be awkward depending on what each MCU is doing.
[UPDATED] Universal Fan Control Schematic Review - Page 1
Forum section: electronics / projects

author: DigitalDesigner
author_rank: Contributor
timestamp: April 09, 2025, 09:08:21 pm
content: NOTE: I uploaded the wrong schematicCorrect schematic attached nowHi,I designed a circuit to control all the following fan types just by configuring one jumper and connecting a couple of wires differently:- 2-wires with speed control (modulating the fan voltage)- 2-wires full speed (no speed control)- 3-wires with speed control and tacho (modulating the fan voltage)- 3-wires full speed (no speed control) and tacho- 4 wires with speed control and tacho (modulating speed with 5V PWM signal)The various configurations are shown on the attached table.Is that correct? Any feedback and suggestions are appreciated.Thank you

author: thm_w
author_rank: Super Contributor
timestamp: April 11, 2025, 12:05:19 am
content: I'm not sure what the schematic is trying to show, an opamp driven by what? Then how does this control the fan? and why is there an inductor to ground on the output?Did you attach the wrong file.

author: DigitalDesigner
author_rank: Contributor
timestamp: April 17, 2025, 09:40:56 pm
content: I uploaded the wrong schematicCorrect schematic attached nowThank you @thm_w for replying, I would not have noticed.

author: wraper
author_rank: Unknown
timestamp: April 17, 2025, 09:52:29 pm
content: QuoteIn other words fan killer, user annoyer (due to fan emitting weird noises). DC brushless fans must not be PWMed period.

author: eutectique
author_rank: Frequent Contributor
timestamp: April 18, 2025, 10:05:48 am
content: The convention is to lay the pins out as follows: GND -- Power -- Tacho -- PWM. Compatibility is the obvious reason. You can connect any 3- or 4-pin fan to any 3- or 4-pin controller.https://www.edn.com/4-wire-pc-fan/https://faqs.noctua.at/en/support/solutions/articles/101000081757-what-pin-configuration-do-noctua-fans-use-

author: DigitalDesigner
author_rank: Contributor
timestamp: April 20, 2025, 06:00:59 pm
content: Thank you both
2-3 position Connectors  - Page 1
Forum section: electronics / projects

author: rakeshm55
author_rank: Regular Contributor
timestamp: March 29, 2019, 04:37:15 am
content: Hi,Are there any 2 -3 pin connectors which can sustain vibrationsboard mountStraight vertical. Thru holeTemp grade -40C to 85 or better.use is to connect panel mount switch contacts to board PCB. I could find lock mechanism in digikey. Looking for vibration which meets shock and vibration

author: Nusa
author_rank: Super Contributor
timestamp: March 29, 2019, 04:56:46 am
content: Latching connectors are everywhere. Often they're tougher than the solder joints on the PCB, or the PCB itself.Unless you quantify shock and vibration, your guess is better than mine as to whether you need something special or not. Do you think you need something that's literally bolted to PCB as well as soldered?

author: beanflying
author_rank: Super Contributor
timestamp: March 29, 2019, 06:04:20 am
content: Search for JST, JST-XH, JST-XHP or variants on those. Fairly easilly available from 2-8 pins or as a Kit to get started like thiseBay auction: #183222237437Used a lot for model aircraft LiPo battery charing leads so you will also find them with leads already attached which may save time depending on your application or if you don't have a small crimp tool.eBay auction: #302615152624For more severe vibration there is similar ones with better locking clips again if you think you need them.
2.45GHz to 2.85GHz VCO Design with Infineon BFP420 - Page 1
Forum section: electronics / projects

author: neilhao
author_rank: Regular Contributor
timestamp: May 10, 2021, 06:33:13 pm
content: I designed a 2.45GHz to 2.85GHz VCO Design with Infineon BFP420 Wideband Silicon NPN RF Bipolar Transistor.The performance is almost same as the theoretical design. According to the waterfall diagram, the VCO is still linearly tunable from about 2.35Ghz to beyond 2.7Ghz.I am sure this design could be turned to work even at 10Ghz.The design details:http://uniteng.com/index.php/2021/05/02/2-45ghz-to-2-85ghz-vco-design-with-infineon-bfp420-wideband-silicon-npn-rf-bipolar-transistor/
2.4G SMD antenna layout questions - Page 1
Forum section: electronics / projects

author: hbozyq
author_rank: Contributor
timestamp: July 15, 2023, 11:38:40 am
content: Hi all. I'm now trying to design a bluetooth module for vesc dongle.I never dip my toe into anything exceed MHz so I'm asking for help here.The main question is I'm unwilling to use PCB antenna inorder to avoid potential failure. I turn to SMD antenna like this:https://www.lcsc.com/product-detail/Antennas_Rainsun-microwave-Tech-AN2051-245_C99727.htmlBut I got no idea how to connect it to the circult. The reference of RF chip design is showned in the attached drawing. And I wonder what should I pay attention to while layout.The chip I'm using is NRF51822:https://infocenter.nordicsemi.com/pdf/nRF51822_PS_v3.1.pdfCheers!

author: hbozyq
author_rank: Contributor
timestamp: July 15, 2023, 12:28:28 pm
content: Accoring this guidelines(https://devzone.nordicsemi.com/guides/hardware-design-test-and-measuring/b/nrf5x/posts/general-pcb-design-guidelines-for-nrf51-series), it seems all I need is a balun an a 50ohm chip antenna and get rid of all the discrete component making my life much easier. Definite be a good news.
2.4GHz radio control protocol? - Page 1
Forum section: electronics / projects

author: deephaven
author_rank: Frequent Contributor
timestamp: August 19, 2011, 01:07:02 pm
content: I notice that a lot of radio control model aircraft etc now use 2.4GHz rather than the lower frequencies. Does anyone know if they use a standard protocol like Zigbee or similar or is there one dedicated to that application? Just curious.

author: kaptain_zero
author_rank: Regular Contributor
timestamp: August 20, 2011, 03:32:24 am
content: They still use PCM (pulse code modluation) but proprietary spread spectrum transmissions. No two manufacturers equipment is compatible. Notable exception is JR/Spektrum who share their technology as far as I know.RegardsChristian

author: deephaven
author_rank: Frequent Contributor
timestamp: August 21, 2011, 05:51:30 pm
content: Thanks Christian.

author: RCMR
author_rank: Frequent Contributor
timestamp: August 22, 2011, 12:47:11 am
content: As Christian has said, there is no "standard" for the protocols used now that RC gear has gone to 2.4GHz.In the old FM ("longwire) days, there was a defacto standard that involved the use of a pulsetrain (one for each channel) with a median width of 1.5mS and a variance of (usually) +/- 500nS. Each frame (series of channel-pulses) was demarked by a sync pulse that was generally 3mS or longer, depending on the number of channels encoded. The standard frame-rate was around 20mS (50 fps).Now however, each manufacturer has come up with their own method for encoding the channel positions, each striving to produce the lowest-latency and highest redundancy.None of these protocols are well documented -- since they're considered "proprietary" by most manufacturers. However, a little work with a logic analyzer will likely reveal a whole lot.The only systems that use existing standard base protocols (or did) are the XPS and (I think) the Jeti ones. They are/were based on ZigBee.
2.4GHz transmitter - BX pin? - Page 1
Forum section: electronics / projects

author: alexig
author_rank: Contributor
timestamp: March 18, 2015, 09:19:11 am
content: Hi all,I recently purchased a 2.4GHz transmitter/receiver and I'm wondering if anyone knows what the BX pin on the PCB stands for On the module I received, it had BX soldered to ground and I had to do the same on the receiver side.Was initially looking for using this in conjunction with a quadcopter that had an existing 2.4GHz link but the transmitter is spewing out RF no matter what channel I set it to, sounds like I'll need to go with 5.8GHz. I went to measure the temperature of the transmitter with an infrared thermometer and it was affected by the RF - was reading 200C and higher!Thanks

author: Psi
author_rank: Super Contributor
timestamp: March 18, 2015, 09:37:30 am
content: BX is the band select pin. (in conjunction with the S pin which you don't seem to have exposed)If you dont connect BX to ground an internal pullup will make it highA high BX pin on 5.8ghz transmitters changes the band to band E, not sure about 2.4ghz versions but it likely just selects a different 2.4ghz bandHave a look at RTC6705 datasheet, its a 5.8ghz chip but the BX pin info might be useful.

author: alexig
author_rank: Contributor
timestamp: March 18, 2015, 01:02:58 pm
content: Thanks for that Psi. I've desoldered the BX connection and was able to find 1 channel which works better than the others. Unfortunately the range is only about 2-4m so I think I'll have to go with the 5.8GHz transmitter.
2.4V zener diode and its usefulness - Page 1
Forum section: electronics / projects

author: nuno
author_rank: Frequent Contributor
timestamp: April 12, 2017, 02:02:53 am
content: I've been trying to fix a board which has an AC-DC converter (from mains). This converter is centered around aVIPer53chip, that has a pin where to connect a compensation network (for dynamic characteristic control). The board designer's decided, for some reason, to add a 2.4V zener diode to that pin (BZX84-C2V4), although the chip's datasheet never mentions/suggests such diode. I look into the diode's curve from the datasheet and it puzzles me, as it looks like a really bad zener... is the board designer somehow counting on the zener's characteristic for the loop's compensation network? Like, counting on more than just the voltage clamping action. I'm not finding this diode (nor similar; 2.4V isn't common) locally and would cost me more than 10€ to get it from abroad, so I was exploring the possibility of replacing it with 4 x 1N4148.Thanks for any insight.
2.5Ghz 12 digit freq counter project from Aus - Page 1
Forum section: electronics / projects

author: Deathwish
author_rank: Unknown
timestamp: May 30, 2015, 08:10:15 am
content: I found this earlier, thought it was rather interesting, that and the fact you can buy the bits still, and that it is set up with another project from 2009, a GPS frequency reference . have a look.http://www.siliconchip.com.au/Shop/9/1045

author: Deathwish
author_rank: Unknown
timestamp: May 30, 2015, 08:34:25 am
content: The GPS frequency reference project.http://www.siliconchip.com.au/Shop/6/1489

author: German_EE
author_rank: Super Contributor
timestamp: May 30, 2015, 08:35:37 am
content: I have this counter sitting on my workbench right now. It was published in the UK by the magazine Everyday Electronics.

author: Deathwish
author_rank: Unknown
timestamp: May 30, 2015, 08:47:19 am
content: I know, that is where I originally found the article and then went hunting on the Aus site for parts availability. Is it good ?. I like the GPS reference project too. Nice to have hanging around

author: dom0
author_rank: Super Contributor
timestamp: May 30, 2015, 09:49:12 am
content: Looks like a classic gated counter (60s tech). Resolution proportional to input frequency and gate time.
2 button, 3 stage controller for heated joint massager - Page 1
Forum section: electronics / projects

author: OwenT
author_rank: Newbie
timestamp: January 26, 2021, 07:37:08 pm
content: I am in a class in which we are building a heated joint massager. Just like this pretty much.https://www.amazon.com/Heating-Massage-Support-Adjustable-Arthritis/dp/B07SQ22QWFI am working on the heating bit as well as controlling the heating and vibration. A lot of the products already available use the same 2 button, 3 stage controller. I am trying to find where I could buy them but I can't. I can only find single button ones likehttps://www.ebay.com/itm/5V-15V-Heated-Vest-Gloves-Knee-Pad-DIY-Temperature-Controller-Rheostat-Switch/402516284752?hash=item5db7d71550:g:hi8AAOSwX-Bfl5ErThere are lots of these switches and they are all pretty much the same. They run at 3 levels. 3.7v, 7.4v, and 12v. Some have the temperature sensor, some don't. I might like to find one like this that I can get relatively soon and not in 1 or 2 months from china.I would like to find this button controller but my searching so far hasn't been successful. I'd appreciate it if someone has some tips on where to look.I don't know exactly how these work but I assume they have some kind of microcontroller in them. It would be great if I could toy with the voltage level settings myself but I don't think that's possible. Anyone know if there would be a way to do that?

author: robzy
author_rank: Regular Contributor
timestamp: January 27, 2021, 06:14:34 am
content: Quote from: OwenT on January 26, 2021, 07:37:08 pmIt looks like your search has been successful. Why don't you buy two of the switches that you found on eBay?Quote from: OwenT on January 26, 2021, 07:37:08 pmDon't use the buttons to control the heat and vibration directly. Instead use them as inputs to an Arduino (for example) which can then control the heat and vibration.What class is this for? Electronics class? Highschool or college?Quote from: OwenT on January 26, 2021, 07:37:08 pmYou can pay more for faster shipping from China.

author: jonpaul
author_rank: Super Contributor
timestamp: January 27, 2021, 10:42:24 am
content: DANGER: Beware of Li Ion batteries charging and fires, explosions.Huge liability if even a singe failure occurs.Chine = ZERO QC or responsiibilty.Jon

author: OwenT
author_rank: Newbie
timestamp: January 30, 2021, 07:47:08 am
content: Thanks, both of you.For now, I think we will be prototyping with those kinds of switches. The goal is to make this as market-ready as possible, so I'm basically trying to replicate what I have seen that's good but improve it if possible. This is for a university class.
2 cell lipo (6.8V-8.4V) to 14V Synchronous Boost converter - Page 1
Forum section: electronics / projects

author: Electro Dodo
author_rank: Contributor
timestamp: September 17, 2024, 03:55:02 pm
content: HelloI tried to design a boost converter to go from 2 cell lipo to a bit above 3 cell lipo voltage.I used the TPS61288, because it includes all switching components, and can deliver ca 4A on the output.Datasheet:https://www.ti.com/lit/ds/symlink/tps61288.pdf?ts=1726578413546&ref_url=https%253A%252F%252Fwww.mouser.de%252FFor the component selection I stuck to the datasheet, as much as possible.I used multiple smaller capacitors on the output than recommended, simply because it's cheaper for me in manufacturing.The same goes for splitting up Rc in Rc1 and Rc2.The entire compensation network was simply copied from the reference design, because I don't know enough about control systems to design them myself.according to the Ti forum, using the reference design values should be fine.For the board layout I tried to stay close to the layout example.Only the Vin pin I routed differently because the layout example didn't connect it to the supply voltage?All in all, this is the fourth PCB I designed, so I would be grateful for all the feedback and advice I could get, before I get it manufactured.
2 channel isolated testbench power supply - Page 1
Forum section: electronics / projects

author: bogdant
author_rank: Regular Contributor
timestamp: November 14, 2019, 06:24:57 am
content: I am trying to design a 2 channel liniar power supply: 0-30V, 0-2A. I have a STM32 used to measure current and voltage. My question to you is: If I have separate gnd_ch1 and gnd_ch2, what topology is used to measure current and voltage but the supply to remain isolated.

author: rvalente
author_rank: Frequent Contributor
timestamp: November 14, 2019, 11:31:50 am
content: For each measurement go with a uc. Suplly them with a flyback power supply with multiple secondaries (or use a off ghe shelf brick). Feedback de values with an photocoupler.Check the isolated channel scopes service manual for inspiration.

author: xavier60
author_rank: Super Contributor
timestamp: November 14, 2019, 01:39:46 pm
content: JuanGg uses two controllers in master/slave.https://juangg-projects.blogspot.com/2019/05/linear-lab-power-supply.html
2-Channel Picture-In-Picture Video Generator - Page 1
Forum section: electronics / projects

author: gekoch
author_rank: Newbie
timestamp: September 02, 2015, 04:26:20 pm
content: HyI need a way to see two video signals on one video feed. So I got two cameras one is the main and the other one should be overlayed at the right lower corner (PIP).I currently own this product here:http://www.securitycamera2000.com/products/4-CH-Camera-Video-Quad-Processor-Splitter-with-VGA-Video-Output.htmlIt works great however I just need two inputs and it needs to be as small and light as possible. How hard is it to build one DIY with current available hardware likeRaspberry Pi etc.? Has someone experience in this kind of project?Video-Signal: Pal / 25fpsAndy
2 channel TFT stndalone `scopes to build into a project? - Page 1
Forum section: electronics / projects

author: Chris Wilson
author_rank: Super Contributor
timestamp: August 28, 2017, 01:15:25 pm
content: Does a two channel TFT type screen, cheapish standalone `scope exist that could be built into a project as a permanent monitor scope? I would like to add a 2 channel `scope to a LF amp projetc to have switched inputs monitoring gate and drain waveforms on the Class D output FET's and monitoring a "Scopematch" circuit that reads antenna current and voltage (seehttp://njdtechnologies.net/want-a-little-more-info-than-an-swr-meter-alone-can-provide-meet-the-scopematch/) Thanks.

author: JPortici
author_rank: Super Contributor
timestamp: August 28, 2017, 01:19:55 pm
content: jye tech low cost scopes? if the bandwidth/samplerate matches your needs..http://www.jyetech.com/index.php

author: Chris Wilson
author_rank: Super Contributor
timestamp: August 28, 2017, 01:50:12 pm
content: Quote from: JPortici on August 28, 2017, 01:19:55 pmRight, that 094 model looks interesting, and could be adapted, I think, to mount behind a panel cutaway! Thanks for that, I'll see if anything else is mentioned, but it looks promising.
2 Differently Scaled current sensors for Space Vector Modulation Motor Control - Page 1
Forum section: electronics / projects

author: Glenn0010
author_rank: Regular Contributor
timestamp: December 25, 2017, 09:20:57 am
content: So correct me if I'm wrong but in sensorless control using space vector modulation you measure the current to know the rotor's position and hence you can know how to drive itAs I underetand At low rpm the problem is the current is small and hence you cannot measure it properly.To solve this issue, lets say you, have shunts as current sensors. Couldn't you connect 2 differential op amps to each shunt? One would have a high gain to get an accurate current measurement at low speed while the other would have lower gain to measure at high speedWould this work? And you would do away with hall effect sensors

author: Rerouter
author_rank: Super Contributor
timestamp: December 25, 2017, 10:42:47 am
content: Why not just use the hall sensor for feedback?I am not fully able to understand your question, but at a guess its to use a small 3 phase motor like one for a quadcopter as a servo motor.At near 0rpm. You really do need feedback, and a hall sensor may work so long as it meets your requirements for final position accuracy.What the electronic speed controllers for quads do is time the zero crossing of the generated emf of a coil. Which is 0 at 0rpm. And very tiny at rpms above that. This can still be used at low rpms as long as the system has a fair amount of inertia. As its predicting when the coils are aligned to ramp up the current in a given coil.

author: Leo Bodnar
author_rank: Frequent Contributor
timestamp: December 25, 2017, 11:11:37 am
content: Quote from: Glenn0010 on December 25, 2017, 09:20:57 amAre you sure you you are using right terms?Sensorless means no sensors at all, not even Halls. And then you use BEMF to find out the current position.And yes, dual gain opamps were used in such configuration forever but I am only aware of DIY products. To be honest, it is pretty useless unless you are making a drive that can control huge range of motor currents. If you size it to a particular motor 10 or 12 bits are more than plenty.Leo

author: filssavi
author_rank: Frequent Contributor
timestamp: December 25, 2017, 02:34:04 pm
content: If it were that simple everyone would be doing that...Unfortunately you are confusing 2 different problemsThe current sensing is needed for field oriented control to control torque in both sensors and sensorless controls.To estimate rotor position in sensorless mode you use a flux observer, by sensing the back-emfs, at low rpm those are weak and that is the problemThis problem can't be solved by gain alone first of all at some point (sooner than later) you'll run into noise issues.Another problem is that at 0 rpm you don't know how the rotor is oriented so you need some other technique (high frequency injection)
2 Layer PCB with PCIe? - Page 1
Forum section: electronics / projects

author: adjdjaa
author_rank: Newbie
timestamp: October 06, 2022, 01:00:21 pm
content: I’m designing a small PCB (under 2x2 inches) which acts as a interposer between a single lane PCIe connector (X1) and another PCIe connector. I’ve calculated a width of the trace as per a coplanar differential microstrip and it meets the 100 ohm impedance. I know it wouldn’t be as good as a 4+ layer stack up but because of a number of reasons, I can only use 2 layer.Could this work?Thanks)

author: m98
author_rank: Frequent Contributor
timestamp: October 06, 2022, 05:01:29 pm
content: How do the lanes get on and off your PCB? Which baudrate do you need?

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 06, 2022, 08:32:23 pm
content: Baudrate? PCIe starts at 2.5GHz (v1)

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 06, 2022, 09:01:48 pm
content: Note you can at least use thinner (0.8mm say) board stock. CPW (or CPWG) will probably have different Z_CM, though I don't know offhand how different from normal, or how picky PCIe is about that.Getting solid grounds will be very important as well, keep in mind the common mode range is only a fraction of a volt for 1.2V receivers. It takes very little interference to stuff that up.Tim

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 07, 2022, 04:57:17 am
content: I don't think is so critical? PCIe allows 8ns skew, which is a lot.You can also invert the signal polarity, the PCIe HW will handle this automatically.I've hacked a BGA CPU with unrouted SATA pins by lifting it, soldering very fine enamelled wires, fixing with UV mask, the wiring them over the pcb for ~30mm before soldering to a sata connector.Never had any issues, the board died recently after 10 years of use.Sata and PCIe signals are pretty similar!

author: Berni
author_rank: Super Contributor
timestamp: October 07, 2022, 05:44:25 am
content: You can do it on 2 layers if you run the diff pairs really close together and surround them in ground.PCIe is surprisingly robust tho. I have run it over 15cm of just regular 1.27mm pitch ribbon cable with the ends criss crossing all over the place and it worked fine. So over such a tiny board PCIe would still work even if you do a horrible job routing it.I also made some 1x PCIe to SATA connector adapters on 2 layer boards any it worked fine (Keysights high end scopes run PCIe over SATA cables and i was repairing one)