hybridfree/eevblog-posts huggingface dataset:
The fancy sensor I used in my project - Page 1
Forum section: electronics / projects

author: robint91
author_rank: Contributor
timestamp: February 01, 2015, 07:46:29 pm
content: I have posted yesterday about my project that I opensourced but I want to show you the sensor we used.https://bytebucket.org/robint91/vmarker-hardware/raw/212bf545da01ae0b976a91a7228cb259b6f10bf9/Datasheets/PAC7010LU%20Specification%20V1_091202.pdfIt is a IR camera with onboard image processing, give 2D coordinates of blobs and it does so with an update rate of 200Hz. It is controllable with a UART interface. It can detect up to 8 of those blobs. So any arduino,pic, arm MCU can read the uart data and figure out what to do with the coordinates. Similar as the wiimote (it is almost the same except the UART instead of the I2C).I have a code example onwww.vmarker.org/opensource

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 01, 2015, 07:52:12 pm
content: How available is it ?

author: robint91
author_rank: Contributor
timestamp: February 01, 2015, 07:55:51 pm
content: You need to have some contacts but I can get 300 pcs quite easy. It took sometime to set those up. In general there is some few weeks lead time.You don't find them at any normal distributor, which is sad...

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: February 01, 2015, 08:15:08 pm
content: Hmm, nothing in datasheet say it uses IR.

author: robint91
author_rank: Contributor
timestamp: February 01, 2015, 08:43:59 pm
content: On the seconde page it says some sensitivity parameter on 940 nm which is infrared.
The Forum Bots are helically fastening me to the wall - Page 1
Forum section: electronics / projects

author: CharlieWorton
author_rank: Regular Contributor
timestamp: February 28, 2020, 11:08:21 am
content: And no, i don't know why it's doing this to me. Deleting images doesn't delete images. It insists that small files are too large. Perhaps the moderator would be kind enough to kill this post, as well as the person that wrote the software. Sigh. >Charlie
The Future of the 555 Timer - Page 1
Forum section: electronics / projects

author: sentry7
author_rank: Regular Contributor
timestamp: December 23, 2015, 03:54:05 pm
content: Hey guys,I was recently looking at various 555 timers from various manufactures including TI and STMicro. The introduction and white papers from many manufacturers state the timer's status as "Not recommended for new designs". Why is this? Is there a successor to this long lived and matured product? Is there something inherentlywrongwith the timer? What is the future of the 555 timer?

author: SeanB
author_rank: Super Contributor
timestamp: December 23, 2015, 04:02:17 pm
content: TI and STM are closing the fabs where they make them, so are not going to produce any more of them in the new fabs they have. Plenty of other manufacturers though who still make them, so they will still be found as new, or as older stock from some inventory that has a few million excess they want the shelf space back from.

author: Pjotr
author_rank: Frequent Contributor
timestamp: December 23, 2015, 04:26:00 pm
content: I'll guess this concerns the bipolar version. CMOS versions like TLC555 are still shown as "active".

author: Zero999
author_rank: Super Contributor
timestamp: December 23, 2015, 07:22:08 pm
content: I'm surprised it's still made.What about other old ICs which have all past their sell by date, such as the µA741? Are they stopping making them too?

author: free_electron
author_rank: Super Contributor
timestamp: December 23, 2015, 07:34:09 pm
content: past its prime. you can get a full blown cpu cheaper these days

author: calexanian
author_rank: Super Contributor
timestamp: December 24, 2015, 04:51:38 am
content: This does not take package style into account. Just a quick Digikey search.PIC10F200 is all of .35 each in spool quantity.MSP430G2230 is .45 ea in qty. and has an A/D to boot and some other nifty features.This is interesting.The price range for 555 I from .07 to 3.60 for a special bare die 2.1 mhz version. I did not know this but Micrel has a similar style part, not pin comparable, but similar in concept that operates up to 5mhz. Most likely targeting designs where a simple timing circuit is beneficial but the frequency response of a traditional timer is not high enough.So the plain old 555 timer is still lower in price, and it appears other companies are making them such as ST,NXP, NJR, and Diodes inc. but I would really recommend in peoples learning of electronics, soon after mastering the 555 people begin playing with MCU's. They are cheap and IDE's and programmers are practically free.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 24, 2015, 05:05:08 am
content: Dunno about the future, but the present is looking good.http://www.ebay.com/itm/2pcs-NE555-adjustable-frequency-pulse-generator-module-For-Arduino-Smart-Car-M92/301724198523?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D34494%26meid%3D5b09c896ba1d4c8ea757038740021f98%26pid%3D100005%26rk%3D3%26rkt%3D4%26sd%3D281689387718
The hand of noise reduction, or WTF is going on with signal integrity? - Page 1
Forum section: electronics / projects

author: Artlav
author_rank: Frequent Contributor
timestamp: March 01, 2015, 07:48:32 pm
content: Spot the difference between the two images:I was measuring output noise of a buck converter (across the load, 1 V, 1 A, 1 Ohm), part of which is on a breadboard.The scope shows some large spikes on switching (100 KHz). Not surprising, considering the situation.I was about to turn it off, for which purpose i held the battery pack...At which point the spikes diminished a lot, both in width and magnitude.I did some hand waving and touching - the controller board is non-responsive, touching any rails don't change anything much.Touching the scope connectors have a little bit of an effect.Touching the MOSFET tab have about half of the effect.Touching the other battery pack have no effect (they share the negative wire).What is going on here?I suspect it's a signal integrity issue, since there is no observable effect on performance, but what can cause it, or how to fix it?Close-up of the breadboard:

author: Neilm
author_rank: Super Contributor
timestamp: March 01, 2015, 08:56:16 pm
content: Most likely your hand is providing come capacitance to earth. As the scope is referenced to earth, this reduces the noise shown.

author: electr_peter
author_rank: Unknown
timestamp: March 01, 2015, 09:21:34 pm
content: Is your scope grounded? May be problems with earth

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 01, 2015, 11:09:25 pm
content: What is it? A gate driver?Looks to be that it's generating a rather significant AC voltage drop across internal grounds (it seems there is no ground plane?) or the connector wires. If the risetime is sharp, this can be significant, several real volts worth. The ringing is a 1/4 wave stub mode, of the wires going to the battery and its stray capacitance; I would guess it's pretty high, like 100MHz or so? The current is returned to ground through the scope probe, hence the error in the probe reading (ground bounce).The damping occurs when your body's capacitance and resistance dampen the ringing; the peak amplitude is more or less unchanged (take a close zoom and check it out!).A very rough approximation of body capacitance is 100 to 10k ohms, in series with < 1pF (hovering nearby) to 100pF (grabbing tightly).Tim

author: tggzzz
author_rank: Super Contributor
timestamp: March 01, 2015, 11:30:51 pm
content: I suspect you are seeing the effects of too much parasitic capacitance and inductance.A wire's inductance is ~1nH/mm. V=Ldi/dt. Estimate your current change and the interval in which it changes, and I suspect you will be surprised but the voltages. Solution is to reduce wire's length, especially a scop probe's ground lead. See the AN-47 and Tektronix primers listed athttps://entertaininghacks.wordpress.com/2015/02/25/oscilloscope-probes/The breadboard will have large capacitances between tracks, which will encourage curent flows and which will resonanate with wire inductance. I = Cdv/dt, so given the capacitance, voltage change and time interval, you can estimate the induced voltage.
The importance of not assuming! - Page 1
Forum section: electronics / projects

author: David_AVD
author_rank: Super Contributor
timestamp: July 29, 2012, 10:48:00 pm
content: Last week I bought a dual banana posts to BNC adapter like the one pictured:Luckily I tested it before putting it into my box of adapters. The black post was not connected to anything!That would have caused some confusion and highlights the importance of checking even brand new leads, etc.I contacted the supplier and they sent us a new one at no charge. And yes, I checked the replacement as well.

author: SeanB
author_rank: Super Contributor
timestamp: July 30, 2012, 05:02:17 am
content: Oops....... Yes, that would be a real head scratcher for sure.

author: saturation
author_rank: Super Contributor
timestamp: July 30, 2012, 04:06:36 pm
content: If you buy these for oscilloscope use and its a no-name brand, its characteristic impedance can be off, and worth checking if it concerns you. Its nominally 50 ohms, if not it introduces its own distortion with RF. A real Pomona 1296 adapter is about $15, the no-names are $5 or less. For RF use, construction materials and strict tolerances will matter.

author: Short Circuit
author_rank: Frequent Contributor
timestamp: July 30, 2012, 06:57:26 pm
content: Real 'danger' of such mistake is a setup where DC ground is ok through another probe or through safety earth.This can yield a severe fuckup of the measured signal. Especially annoying when the fuckups are similar to potential shortcoming of the circuit, such as excessive ringing in switchers.Of course, you don't use a BNC adapter to measure that generally, but normal probes can have these problems too.BTW characteristic impedance is hardly an issue with these adapters. Impedance of two banana jacks can be determined but most likely not 50 ohms, and impedance of the two T&M wires into the bananas is not defined at all. For other adapters, such as BNC to BNC, BNC to SMA, etc, I agree. Although it does not matter for many applications. Many scopes don't have 50ohms termination at all, so I doubt the impedance mismatch from a dodgy 50 ohms plug will make much of a difference.

author: David_AVD
author_rank: Super Contributor
timestamp: July 30, 2012, 09:39:41 pm
content: The intended use for the adapter in my case was to get a (relatively low frequency) signaloutof a function generator. I guess there could be occasion to use it on a CRO, but I'd normally be using the probe.

author: EEVblog
author_rank: Unknown
timestamp: July 30, 2012, 10:29:31 pm
content: I can picture many hours wasted on debugging such a simple thing, as it's the last thing you'd suspect. Especially when you are testing an unknown setup where there could a ton of things at fault in your new design etc.Nasty.Dave.

author: David_AVD
author_rank: Super Contributor
timestamp: July 30, 2012, 10:33:12 pm
content: Yeah. A broken connection to the red terminal would reveal itself fairly quickly, but a missing ground has the potential to be so insidious.
The Internet in 1969 - Page 1
Forum section: electronics / projects

author: Homer J Simpson
author_rank: Super Contributor
timestamp: December 10, 2013, 02:12:40 am
content: Another YouTube find you might enjoy.KT

author: xrunner
author_rank: Super Contributor
timestamp: December 10, 2013, 02:34:05 am
content: At the core of it, it's really not a bad prediction.

author: nctnico
author_rank: Super Contributor
timestamp: December 10, 2013, 03:12:53 am
content: And before you know it we all walk around like this:

author: calexanian
author_rank: Super Contributor
timestamp: December 10, 2013, 03:25:55 am
content: If they only knew back then. O0

author: Jon86
author_rank: Frequent Contributor
timestamp: December 10, 2013, 04:58:43 am
content: 'What the wife selects on her console, will be paid for by the husband on his counterpart console'

author: Stonent
author_rank: Super Contributor
timestamp: December 10, 2013, 06:43:52 am
content: Quote from: Jon86 on December 10, 2013, 04:58:43 amOnce she gets done vacuuming the carpet in her high-heels and pearls and making you a perfect beef tenderloin.

author: mtdoc
author_rank: Super Contributor
timestamp: December 10, 2013, 06:54:44 am
content: Quote from: Stonent on December 10, 2013, 06:43:52 amWait a darn second. Now why did that first part come true but not that second part...

author: dannyf
author_rank: Super Contributor
timestamp: December 10, 2013, 07:46:38 pm
content: QuoteThat cannot be true because it didn't feature Al Gore who as we all should know invented the internet.

author: Stonent
author_rank: Super Contributor
timestamp: December 10, 2013, 08:19:19 pm
content: Quote from: dannyf on December 10, 2013, 07:46:38 pm
The IV22 VFD Clock - Page 1
Forum section: electronics / projects

author: Rolo
author_rank: Regular Contributor
timestamp: November 18, 2018, 03:22:42 pm
content: The long road from an idea to a working unit. The IV22 VFD Clock.The idea: Do something with old stock VFD tubes. I like VFD display's, you can get a nixie clock anywhere but VFD based models are less common.So I designed one, the key items in the design were:* Low power consumption as possible* Must have power save mode* Automatic brightness control based on environment light* Must work on a single 5V supply* NTP time sync trough wifi network* Touch sensor to show date or do other things* Automatic timezone and daylight saving time correction* Design a case that can be made without special tools (or have it made)* Flexible design so it could fit in ready made cases or old clock housings* RGBW Led's behind the tubes, as status indicator or/and backlight* Easy to use, minimum user input needed, it should just work when you plug it in.* Must provide a working unit that can be placed in my livingroom and stay's there with approval of the other family members* Software update over the air* Fun to build, no hurryI have made an album with various pictures from some stages of the project , I hope the link works.Do not want to add that many pictures in this post.Now I'm looking for a catching name for this clock, any ideas?If you want more details about the project please ask, I will try to answer them.Some details, it has a Wemos D1 mini board as controller, software made in the ESP8266 arduino suite.The clock takes about 550mA when the anodes are on the highest brightness and the leds off.https://photos.app.goo.gl/gnLn7QdxzjhkCnPB9My camera picks up the VFD segments way to bright, in real life they are easy to read.

author: Rolo
author_rank: Regular Contributor
timestamp: November 30, 2018, 10:01:02 am
content: Update on this project : I have mounted a clock module in a ready made (Ikea) bamboo box and put a "Glass Look" Arcyllic front on it. I have added three photo's of it to the album.https://photos.app.goo.gl/gnLn7QdxzjhkCnPB9

author: RobK_NL
author_rank: Frequent Contributor
timestamp: November 30, 2018, 11:20:40 am
content: That looks very good.A neutral density filter in front of those VFD's would do wonders for the contrast, though.

author: Rolo
author_rank: Regular Contributor
timestamp: November 30, 2018, 11:55:35 am
content: Thanks, in real life the contrast is much better, my camera picks up the segments too bright.
The limit of active clamp converter, adjustable? - Page 1
Forum section: electronics / projects

author: Miles Teg
author_rank: Regular Contributor
timestamp: June 28, 2024, 12:49:43 pm
content: Hello,I'm on upgrading a power supply design in one of my product. Getting power from PoE Line. Getting already good control over PoE management chip (TPS2373)I would like to adapt the power stage commanded by our MCU.Setup the TSP2373 to 20W - 50W - 90W class when needed and adjust our converter stage to output 20V for the 20W use and up to 40V for the 90W.I'm looking on the Forward clamp converter topology (around UCC2897 for example), but I'm not sure of its ajustability capabilities and the possibility of low delta input-output (52V input, 40V output 2,3A).Got already one running for a fiw 20W with TPS2375420W: 45Vin to 20Vout 1Aadjustable to90W: 52-57Vin to 40Vout 2,3AHave you any advice or other topology?Where could I get resources and methodology to design such power supply? Want to learn for getting a step further of my experience on Buck-Boost.Thank you!

author: Terry Bites
author_rank: Super Contributor
timestamp: June 30, 2024, 02:10:39 pm
content: Your prayers answered so far as TI parts go. webench.ti.com/power-designer/switching-regulatorOr for LT/ADwww.analog.com/en/lp/ltpowercad.html
The LIR2032 Battery's and Chargers and Datasheets and Amazon Chargers... Help Ah - Page 1
Forum section: electronics / projects

author: Don Warr
author_rank: Newbie
timestamp: February 07, 2024, 05:01:14 am
content: I acquired The LIR2032 3.6v Battery... The Battery Data Sheet say's "Standard Charging Method" = Constant Current at 17ma and Constant Voltage at 4.20V.... Now I acquired charger on amazon that plugs into usb and says FOR charging LIR2032.. But printed on the button cell charger is "output = 4.2v @ 100ma" Question is Is the charger ok to charge battery...PS: The charger Led went from Red (charging) to Blue (charged) OK,, but is it charging at to high a current..??Any comments would be appreciated Thanks....

author: FoxesRule
author_rank: Newbie
timestamp: February 07, 2024, 08:54:56 am
content: Hi there,Do you have a datasheet for the charger? 100mA charge current is definitely too high for a LIR2032 battery... most lithium prismatic and cylindrical batteries recommend a 0.5C charge and an absolute maximum 1C charge rate, but coin cells have more restrictive parameters due to their method of construction.If you take a look at the following "universal" coin cell charger, (https://ctenergy.myshopify.com/products/lir2032-rechargeable-button-battery-charger-set-4-pack) you can see it has different slots for different charge rates for cells (20mA ports for LIR2032/2025/2016/1632/1620/1220 and 40mA ports for LIR2032/2430/2450 rechargeable batteries)You will PROBABLY get away with charging the batteries, but you will definitely reduce your cycle count (number of times you can charge and discharge the battery) and you will increase the risk of the battery failing, possibly causing a small fire. (Even if the battery does not have visible damage during or after charging, gradual incremental damage might cause it to fail when inserted into the device you are using. In other words, most likely the battery will work fine even for 200 cycles, but there will always be the chance of a worst case scenario (small, but still there) that the battery will fail and destroys the device it is in... and fires spreadWhen in doubt, trust the datasheet :-)Kind regards,FoxesRule

author: Don Warr
author_rank: Newbie
timestamp: February 08, 2024, 08:30:43 am
content: Well thanks for a reply FoxesRule... Yes the charger you show is nice,, but I have designed a esp8266 project that needs a coin size battery (wareables),,, the project works well, but needs a separate battery charger.. the project is for 68 seniors in my building, so the nice charger you show is to expensive for each of 68.. Here is link to charger I would like to use.. They don't show other side of charger that says 4.2V@100ma.. but lists the Lir2032.https://www.amazon.ca/dp/B0CHQTYVM7?psc=1&ref=ppx_yo2ov_dt_b_product_details
The Logic Meter - Page 1
Forum section: electronics / projects

author: rea5245
author_rank: Frequent Contributor
timestamp: January 22, 2021, 10:57:30 pm
content: I've made a new type of test instrument: the logic meter. It's sort of a mash-up between a logic analyzer and a multimeter. I've posted the design and source code on GitHub in the hope that someone will take this idea and turn it into a commercial product.I've made a video that demos the product and explains the design:

author: robzy
author_rank: Regular Contributor
timestamp: January 27, 2021, 06:06:23 am
content: Wow! I'm impressed with the amount of engineering that went in to that!One small note - a 30 minute video is not a quick and easy way for someone to get familiar with your invention. I'd suggest continuing to put a bit of time into the GitHub page, making it even clearer and easier to understand, and including some photos.https://github.com/galacticstudios/Logic-Meter
The many faces of the XX431 precision shunt regulator - Page 1
Forum section: electronics / projects

author: JohnnyBerg
author_rank: Frequent Contributor
timestamp: November 05, 2019, 08:30:57 am
content: I am building a precision voltage to current converter, that shifts the voltage level of a Li-ion battery pack to a level that a micro-controller can read. Furthermore, I am not interested in the first 2,5V, the cell is just dead under that level.I have a 12 bit ADC and want to use those 12 bits in the range 2.5 to 4.4V, giving me a base resolution of approx. 0,5 mV.In my design I use a XX431, and that is where its gets messy. For me, 2 factors are of importance: the current needed for regulation Ika (its is a battery operated thing, smaller is better) and the current into the reference pin, witch gives an error in the conversion.Voltage reference have a grade, the xx431 is no exception: the A grade gives 1% accuracy, the B grade 0.5%. There are also C types, they are 2% (I fail to see the logic). Accuracy is not important, as each cell measurement is calibrated.But here is where the shit hits the fan: a XX431 from supplier Y is not the same as the one from supplier Z.Examples (all max values, price per 10):Classic TL431 from TI: Ika = 1mA, Ivref=4 uA $0.20Changjiang Electronics CJ431: Ika = 1mA, Ivref=4 uA $0.03Seaward Elec SD431: Ika = 300uA, Ivref $ 4uA $0.04In my quest for the best I found this one:ATL431 from TI: Ika = 35uA, Ivref=150nA $0.40Is this the one?edit: found the AS431 from Diodes Inc.: Ika 50uA, Ivref=500nA $0.05 .. not as good as the ATL431 but much better price level. Designing is like marriage .. you have to compromise ..

author: AE7OO
author_rank: Regular Contributor
timestamp: March 11, 2020, 05:24:24 am
content: I know it's old...I think I've got your system figured out.You might want to take a look at the OnSemi NCP431/NCP432 in the future.Iref 190nAIka 60uAThese stats are the same for all of the various grades, from AC to BV.$00.30 qty 10Not super cheap, but not bad either.As of 10MAR20, for whatever reason, Mouser has the 432BV's for $00.26, which has the greatest temp range -40 to 125 and 0.5% initial.
The million dollar inverter - Page 1
Forum section: electronics / projects

author: RupertGo
author_rank: Regular Contributor
timestamp: July 24, 2014, 01:15:31 pm
content: Google and the IEEE are offering a $1m prize for the smallest/highest power density kW-scale inverter, of at least 50w/square inch. Which is, I think, a very worthy target.Any team can enter - more details here -https://www.littleboxchallenge.com/R

author: RupertGo
author_rank: Regular Contributor
timestamp: July 24, 2014, 01:30:07 pm
content: Whups - I see this is a duplicate, and I can't delete it. Can it be zapped, pls?R
The necessity of a guardring (LT3080). - Page 1
Forum section: electronics / projects

author: fc3000
author_rank: Regular Contributor
timestamp: August 29, 2023, 07:46:48 am
content: Hi all.I have read the data sheet for the LT3080.It recommends the use of a guard-ring to the SET pin ( because of the high impedance).If instead of a resistor one uses a OPAMP, to control the SET pin, is a guard-ring still necessary.I was thinking that the OPAMP with its low impedance would render the guard-ring unnecessary.(By the way, Dave did not use any guard-ring in the uPSU project!)Am I correct?Regards

author: Marco
author_rank: Super Contributor
timestamp: August 29, 2023, 08:18:37 am
content: Yeah, the output of the opamp is low impedance. It slurps up both the set current and any leakage current.Of coarse with an opamp you will need a voltage reference, the precision set current has become useless.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: August 29, 2023, 11:59:16 am
content: I fully agree.Guard rings only make sense in high impedance circuits and because the output of an opamp is low impedance there is no advantage t adding a guard ring.I also do not understand the attractiveness of an LT3080, especially if yo only use it as a glorified transistor. When you just use a transistor as an emitter follower, and take the feedback for the opamp from the emitter of the transistor, you reduce your EUR5 LT3080 to a 50ct transistor. When you start adding stuff to opamps, you risk instability issues, but simple emitter followers are low risk here and even if you have to struggle a bit with loop instability, it is a good opportunity to learn some more in-depth things about opamps. And in my opinion that is worth more then just trowing in a relatively expensive "no brains required" part.

author: Marco
author_rank: Super Contributor
timestamp: August 29, 2023, 12:52:16 pm
content: The 3081 which is worth the price though, a CV/CC regulator which works without output capacitance saves a lot of components and headaches.
the numeric displays in Goldfinger - Page 1
Forum section: electronics / projects

author: ledtester
author_rank: Super Contributor
timestamp: November 07, 2020, 05:39:31 am
content: Just noticed them again and wondered what kind of technology they are:This is the countdown timer for the nuclear device Auric Goldfinger has set up to explode at Fort Knox.It looks like each digit is made of several pin-point lighting elements.

author: Whales
author_rank: Super Contributor
timestamp: November 07, 2020, 05:45:41 am
content: Stack of sidelit clear plastic/glass sheets with scratches on them? One layer per digit, light scatters when it hits the scratches. I don't know if this has a name.Nice

author: ataradov
author_rank: Super Contributor
timestamp: November 07, 2020, 05:58:25 am
content: It is thishttps://en.wikipedia.org/wiki/Lightguide_display

author: james_s
author_rank: Super Contributor
timestamp: November 07, 2020, 06:36:51 am
content: My friend had a 1980s Honda (I think) with an automatic transmission and I remember the gear indicator in the instrument cluster used a small edge lit display like this. I've seen a picture of a clock somebody built with edge lit numeric displays about 20 years ago but I've never seen one of the displays in the flesh.

author: amyk
author_rank: Super Contributor
timestamp: November 07, 2020, 07:16:41 am
content: Here's what the inside of one looks like:https://stevenjohnson.com/nls/481-display.htm
The one inch square PCB contest - Page 1
Forum section: electronics / projects

author: zapta
author_rank: Super Contributor
timestamp: October 04, 2015, 05:27:15 pm
content: https://hackaday.io/project/7813-the-square-inch-projecthttp://hackaday.com/2015/10/02/the-square-inch-project-challenges-your-layout-skills/That's a $5 order for 3 boards, shipped, from OSHPark.
The output sine signal of DDS (AD9834) is bifurcated by phase - Page 1
Forum section: electronics / projects

author: Katanara
author_rank: Contributor
timestamp: February 10, 2022, 01:33:49 pm
content: Hello! I'm using AD9834 (50 MHz rev.) for generating sine signal with the ability to change the amplitude. I relied on this AD's circuit notehttps://www.analog.com/media/en/reference-design-documentation/reference-designs/CN0156.pdf.Basically it works fine, but there is a problem with output sine. It seems that part of output spectrum has a different phase. If oscilloscope has 200 mV Vpp or greater it looks fine, but if it's smaller we can see the bifurcation by phase.Moreover, if I reduce the amplitude using FS adj. pin, then bifurcation can be observed more clearly. I was disconnecting the DAC (fs to ground via resistor) and output OpAmp - the problem comes from the AD9834. The measurements were performed between Iout and IoutB.I'm attach the oscillograms and the scheme. Thank you.

author: tggzzz
author_rank: Super Contributor
timestamp: February 10, 2022, 01:49:02 pm
content: That's the scope triggering on noise.Reduce the noise before it reaches the scope, or use "autosetup", or use the scope's trigger filtering facilities.On an old analogue scope all the controls are visible (and obvious) on the front panel. With modern digitising scopes the relevant controls will be "hidden" somewhere in the menu system.

author: Katanara
author_rank: Contributor
timestamp: February 10, 2022, 01:58:40 pm
content: Thank you! I'll try it soon.

author: MarkF
author_rank: Super Contributor
timestamp: February 10, 2022, 03:02:23 pm
content: You might be interested in this topic:Looking for <$50 function generator

author: Katanara
author_rank: Contributor
timestamp: February 10, 2022, 03:09:31 pm
content: Thanks! I really need to figure this out
The Perfect PCB Prototype from Circuit Cellar   -   A method on how to make PCBs - Page 1
Forum section: electronics / projects

author: ez24
author_rank: Super Contributor
timestamp: May 10, 2016, 08:32:26 pm
content: http://circuitcellar.com/cc-blog/the-perfect-pcb-prototype/Any comments ?

author: KL27x
author_rank: Super Contributor
timestamp: May 10, 2016, 08:38:14 pm
content: If you take your footprint from the datasheet, you will already know if everything fits?If you want to crowd your board even smaller, you can make your parts library from actual caliper dimensions. But I'd add a little extra for manufacturing tolerances, if you are going to deviate from the datasheet.

author: stmdude
author_rank: Frequent Contributor
timestamp: May 10, 2016, 08:38:32 pm
content: Isn't this why we have 3D previews in our CAD programs?

author: KL27x
author_rank: Super Contributor
timestamp: May 10, 2016, 08:44:42 pm
content: QuoteNow it makes sense. Cramming a PCB, trying to save money, and using thru hole parts is an oxymoron.I'd like to see this guy's website in another 6 months. I bet this will change, lol. Thru hole parts are just a phase we go through.

author: M4trix
author_rank: Frequent Contributor
timestamp: May 10, 2016, 09:28:17 pm
content: Quote from: stmdude on May 10, 2016, 08:38:32 pm+1Besides, the article appeared in Circuit Cellar 156 and that was printed back in 2003 which means way before 3D previews in nowadays CAD software.@ez24,mate, forget about that method cuz it's simply way out of time.
The Plant of a Feedback System - Page 1
Forum section: electronics / projects

author: Wrydog
author_rank: Contributor
timestamp: March 15, 2017, 11:50:40 pm
content: Hello,I'm having trouble understanding how to derive the plant for feedback control. For a dc-dc full bridge converter is it just the Vout equation in terms of Vin? Does it include the output filter?Any help would be appreciated.Thanks.

author: moffy
author_rank: Super Contributor
timestamp: March 15, 2017, 11:58:34 pm
content: I am not sure what you mean by "the plant of a feedback system", but if you mean modelling the control system, then yes you have to include the output filter. They establish poles and zeros which you need to know about(laplace domain).

author: Wrydog
author_rank: Contributor
timestamp: March 16, 2017, 12:05:25 am
content: Yes, I mean in terms of modeling the control system. How is the plant derived?I'm probably overthinking it but none of the control systems textbooks I've looked at say much about it.

author: IanB
author_rank: Super Contributor
timestamp: March 16, 2017, 12:13:14 am
content: By "plant" do you mean the process that is being controlled? That is to say, the part of the feedback loop that is not the control system?If so, you have to come up with a suitable model of the process that adequately represents its behavior. One way to do this is to use suitable model equations for each element of the process, making simplifications as appropriate, and then combine them appropriately.Any good textbook on process control should devote some space to process modeling. You can't compute the control system response if you don't know how the process behaves.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 16, 2017, 12:13:32 am
content: The plant is whatever that block corresponds to, in the loop.If the controller is sensing the output voltage, and the output voltage follows the filter, then yes.If the controller is sensing the voltage into the filter, then no.The controller outputs a control voltage, which is not the supply/input voltage. But the control input is still an input, so your meaning is ambiguous.This is an excellent justification for current mode control: only one pole in the control loop, so the controller can be compensated optimally. The resulting transconductance amplifier (control voltage in, constant current out) is then enclosed in another loop, regulating output voltage.Tim
The Post Apocalyptic Inventor Youtuber on LR and SMPS PSU - Page 1
Forum section: electronics / projects

author: Mechatrommer
author_rank: Super Contributor
timestamp: June 14, 2016, 12:27:59 pm
content: a good youtuber explaining stuffs relating to SMPS and Power Conversion in general, but sadly he only managed up to part 5 (after 2 years now) where the fun part 5 just got into explaining inductance and magnetism basic which imho he did it in excellent way to make easy understanding to beginners like me... esp why the ferrite core and what is practical meaning of "permeability". i wish he can continue part 6 to the end. if you happen to know this guy, please have him a poke and lets support him by giving him a thumbs up... fwiw...part 1...all the way topart 5...

author: diyaudio
author_rank: Frequent Contributor
timestamp: June 14, 2016, 05:12:44 pm
content: Quote from: Mechatrommer on June 14, 2016, 12:27:59 pm2 years already, wow time fly's this is why I dont stick around on the forum so much, eevblog time machine
The practice of using Snubberless triacs - Page 1
Forum section: electronics / projects

author: S. Petrukhin
author_rank: Super Contributor
timestamp: May 15, 2024, 10:36:33 am
content: Hi, freiens!Please share your practice of using snubberless triacs.I'm going to use STMicroelectronics T1635-800G-TR.Is it really reliable on inductive load?Do they have a risk of a short circuit when the power is turned on in the reverse drive circuit (phase crossing)?
The PROG pin of the LTC4054 Lithium charger - Page 1
Forum section: electronics / projects

author: VanitarNordic
author_rank: Frequent Contributor
timestamp: November 15, 2018, 08:59:45 am
content: I have a question regarding the PROG pin of this charger chip.Pulling down the PROG pin with a proper resistor defines the charge current of the battery, but the question is that it defines the maximum current or the resistor value should be adjusted dependent the connected battery capacity?for example, a 1.33K resistor should deliver around 900mA current maximum. then what happens if we connect a 300mA battery? it will get charged at 2C or 900mA or automatically it will get charged at a proper current?

author: Rerouter
author_rank: Super Contributor
timestamp: November 15, 2018, 09:04:23 am
content: It will be charged at that 900mA while in the constant current phase of charging,you need really smart chargers to normalize to 1C charge rate for all batteries, I've played with the Idea, using the mAh / mV scaling to adjust the rate of charge to get the most out of a battery that had to last 7 years, In the end my application allowed me to just lock it at 0.4C, and the datasheet was predicting that would suit its deterioration.

author: VanitarNordic
author_rank: Frequent Contributor
timestamp: November 15, 2018, 10:28:23 am
content: Quote from: Rerouter on November 15, 2018, 09:04:23 amI am thinking of a method to tune this pin electronically rather than mechanically changing the pull-down resistor values

author: Rerouter
author_rank: Super Contributor
timestamp: November 15, 2018, 10:36:46 am
content: Simplest way, use a few resistor values with mosfets to switch them in and out, by combining different ones you can get intermediate values.Seeing as I cannot find a datasheet for your given chip, I cannot say if a DAC approach would be suitable.

author: VanitarNordic
author_rank: Frequent Contributor
timestamp: November 15, 2018, 10:39:35 am
content: Quote from: Rerouter on November 15, 2018, 10:36:46 amThe chip is LTC4054. I had made a typo mistake.
The purpose or function of series non-polar C1-R1 parallel to D - Page 1
Forum section: electronics / projects

author: abdulbadii
author_rank: Frequent Contributor
timestamp: February 10, 2023, 12:16:21 am
content: What is the purpose or function of series non-polar C1 - R1 (24 Ohm resistor) on parallel to rectifying D around SMPS output here ?Help clarify by elaborated explanation, thanks

author: SuzyC
author_rank: Frequent Contributor
timestamp: February 10, 2023, 12:22:24 am
content: This purpose of this r/c is EMI suppression that is caused by fast turn on/turn offs of these rectifier diodes.

author: ajb
author_rank: Super Contributor
timestamp: February 10, 2023, 01:34:31 am
content: It's a type of "snubber". You'll see these in parallel with all kinds of switches--diodes, transistors, even relay contacts--to dissipate energy stored in the inductance of the load/wiring and limit the voltage of the transient that results from the switch turning off.
The Quadrupole Mass Spectrometer - Page 1
Forum section: electronics / projects

author: ikrase
author_rank: Regular Contributor
timestamp: March 13, 2018, 08:05:11 am
content: I've finally bought the first parts to my Quadrupole Mass Spectrometer build: some small air variable caps.

author: ikrase
author_rank: Regular Contributor
timestamp: March 15, 2018, 06:55:57 pm
content: Was originally planning to to build my own 300 KHz to 3MHz (approximately) amplifier - roughly 40W and using Class AB probably. Maybe an IRF510 amp.However I see there are some economical amps of this type on eBay, though most have a bit higher frequency rating that might need toroid rewind.I see that logarithmic power detector amps are also available as eBay Modules.

author: hound
author_rank: Newbie
timestamp: November 09, 2019, 02:41:06 am
content: If you are still working on this project, you might want to check out US patent 5613294. It describes an implementation of a quadrupole mass spectrometer, and it has a pretty detailed description of the electronic circuits used for rf generation, with a circuit diagram.
The RefAmp & General Stuff on Temperature Compensated Avalanche / Zener Diodes - Page 1
Forum section: electronics / projects

author: quantumvolt
author_rank: Frequent Contributor
timestamp: March 30, 2014, 04:31:47 am
content: Open thread to supplement the LTZ1000 and LM399 threads.I thought it would be nice to start with some pictures from the 1960-70s.The RefAmp topology:HP RefAmp - used at least as early as 1963:Fluke RefAmp - first use by Fluke seems to be in 1971:For more modern canned devices there are plenty of pictures on the web.Two schematics showing the basic configuration for an adjustable amplified voltage reference based on the RefAmp:HP 3450A:Fluke 731A:

author: wiss
author_rank: Frequent Contributor
timestamp: October 19, 2014, 04:16:46 pm
content: The ref-amp was used in the fluke 341a as well, dating to -68 or -69 (?)

author: quantumvolt
author_rank: Frequent Contributor
timestamp: October 15, 2015, 02:08:38 am
content: Quote from: wiss on October 19, 2014, 04:16:46 pmThat is correct! I did not know. And the reference schematic is all discrete components and very similar to the HP 3450A over (the refamp as reference and error amplifier, a high gain differential amplifier, and a series regulator element).Thank you very much for this info. I am sorry I didn't see it before now.Since the manual I found on the web for Fluke 341A is dated 1969, and the Fluke 731A manual (I have) is from 1971, I know that Fluke had experience making voltage reference boxes before the (somewhat helpless) 731A.Fluke 341A (attachment below):
the replacement 555 they don't want you to know about - Page 1
Forum section: electronics / projects

author: Zero999
author_rank: Super Contributor
timestamp: December 10, 2022, 06:09:09 pm
content: You're a bit late. Halloween was back in October.

author: Terry Bites
author_rank: Super Contributor
timestamp: December 10, 2022, 06:30:01 pm
content: So halloween is always in october- you learn something new every day.........Is the calendar still a thing? I thought a phone app had replaced that.

author: josuah
author_rank: Regular Contributor
timestamp: December 10, 2022, 07:17:14 pm
content: And here we have a chip die microscopy of that chip.

author: MikeK
author_rank: Super Contributor
timestamp: December 10, 2022, 09:29:25 pm
content: Who doesn't want me to know this?

author: TimFox
author_rank: Super Contributor
timestamp: December 10, 2022, 09:45:20 pm
content: If we told you, we'd have to shoot you...

author: coromonadalix
author_rank: Super Contributor
timestamp: December 10, 2022, 09:59:41 pm
content: Some are high here ??
The Scopewriter - Page 1
Forum section: electronics / projects

author: adriten
author_rank: Contributor
timestamp: May 17, 2021, 04:40:42 pm
content: many years ago I saw an interesting project on an issue of Popular Elecronics and decided to build it Essentialy it is a circuit allowing to display a sentence of max 32 charachters on the oscilloscope CRTYou enter the sentence, charachter after charachter using the relative ASCII code, then you raise a switch and voila the sentence appears on the CRTA few weeks ago I found my prototype in a box and decided to see if after so many years was still workingIt worked but some charachter were no longer availableAt the hearth of this circuit there is an hex 32 bit static shift register acting as the memory and for some reason one of the six channels was no longer workingAfter discarding the idea of buying a replacement as the IC nowadays has become quite rare and expensive I started to think how to replace itStory short,to replace the failing chip I ended up to use FIVE ICs (2x 4053 and 3 x 4517) ; I'm sure a smarter solution does exists Maybe some of you have have a smarter idea (?)Attached is the original schematics (Popular Electronic Aug 74)together with a few pic of my set-upadri

author: adriten
author_rank: Contributor
timestamp: May 17, 2021, 04:44:04 pm
content: apologize for the pic upside-down

author: adriten
author_rank: Contributor
timestamp: May 17, 2021, 04:52:05 pm
content: my set up

author: jfiresto
author_rank: Frequent Contributor
timestamp: May 17, 2021, 07:37:46 pm
content: I think I still have the LSI parts for that project. Just as I was going to use them, I got a stylish, surplus Olivetti TE300 teletype:

author: Benta
author_rank: Super Contributor
timestamp: May 17, 2021, 07:51:09 pm
content: Quote from: jfiresto on May 17, 2021, 07:37:46 pmCool!! Communication at 50 baud. Those were the days!

author: adriten
author_rank: Contributor
timestamp: May 17, 2021, 08:01:44 pm
content: beautiful1960 ?adri

author: jfiresto
author_rank: Frequent Contributor
timestamp: May 18, 2021, 02:47:41 pm
content: I think it was made in the late 1960s. Olivetti still supported the model when we got them in 1978–9. It was pretty high tech for a mechanical, 110 baud teletype. It had a full RS-232 interface and a fair amount of electronics, perhaps to power it up and down when it received new data.It was big change from the 60 words per minute Baudot printer I was bringing up. If I remember correctly that one had a 45.45 baud rate, 1.42 stop bits and a 100V, 60mA current loop interface which could probably work over a line running across the next couple time zones.
The start of creating life in a new analog design. - Page 1
Forum section: electronics / projects

author: mrpackethead
author_rank: Super Contributor
timestamp: January 21, 2016, 07:13:39 am
content: And life begins.

author: daqq
author_rank: Super Contributor
timestamp: January 21, 2016, 09:33:43 am
content: I always wondered how they manufactured the more complicated stuff, thanks!On a related note: There are successful experiments on using evolutionary algorithms with electronics design:http://hforsten.com/evolutionary-algorithms-and-analog-electronic-circuits.htmlhttp://www-verimag.imag.fr/PEOPLE/Nicolas.Halbwachs/SYNCHRON03/Slides/girault2.pdfhttps://en.wikipedia.org/wiki/Evolved_antenna

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 21, 2016, 09:58:24 am
content: Tim
The Start of the End - Final Engineering Project - Page 1
Forum section: electronics / projects

author: nick.sek
author_rank: Regular Contributor
timestamp: November 17, 2012, 02:23:20 am
content: Today I start this video series of my final project in the engineering program. I've decided to build a variable speed drive, which will us frequency to control the speed of induction motors, also incorporating a vast array of circuit protection (digital Circuit Breakers), and using feedback to ensure regulation. Soft start and stop is a feature I will want to incorporate as well. This video is the first that will document the entire project from the start to finish and everything in between(both the good days and bad).Hopefully you enjoy...Any feedback is appreciated!http://youtu.be/oydHPlhiH_Y

author: SeanB
author_rank: Super Contributor
timestamp: November 17, 2012, 06:32:07 am
content: You can find info athttp://www.tinaja.com/magsn01.shtmlfor more about Don Lancaster's sine generation.

author: nick.sek
author_rank: Regular Contributor
timestamp: November 17, 2012, 03:58:55 pm
content: thanks for the link extremely helpful!
The state of ART in electronics, Jim Williams's and others' art thread? - Page 1
Forum section: electronics / projects

author: cdev
author_rank: Super Contributor
timestamp: November 25, 2017, 01:03:21 am
content: I thought this would be a neat subject for a thread..I just read a EDN story about analog guru Jim Williams's electronic art, some of which is pictured in the article. Over the years Ive seen a fair amount of electronics art both in museums, and online. If you've made any electronics art or incorporated artistic elements into projects, please post a photo of it and some info.Here is the EDN article about Williams and some of the images in it.https://www.edn.com/design/analog/4411017/Jim-Williams--The-light-side-and-classic-electronics-art-sculptures

author: David Hess
author_rank: Super Contributor
timestamp: November 25, 2017, 05:35:22 am
content: The first one includes Tektronix ceramic terminal strips which were used in their early oscilloscopes.

author: bd139
author_rank: Super Contributor
timestamp: November 25, 2017, 04:47:26 pm
content: Note sure if this classifies:And now for something more serious:http://golddredgervideo.com/kc0wox/tek/7504/detailedpictures.htm

author: Richard Crowley
author_rank: Super Contributor
timestamp: November 25, 2017, 04:54:18 pm
content: That hanging piece from Mr. Williams certainly gives a good illustration of the term "power rail"! or "ground bus".In that second post, this is a cautionary tale. Several people have been injured or died from shaking a big vending machine and having it fall over on them. That poor component was apparently trying to squeeze the last volt out of that big battery and look what happened.