hybridfree/eevblog-posts huggingface dataset:
Anyone want to guess this IC? - Page 1
Forum section: electronics / projects

author: rx8pilot
author_rank: Super Contributor
timestamp: November 05, 2018, 01:44:40 am
content: Trying to identify a BGA on a Sony monitor PCB. It appears to be in the area that deals with on-board audio, headphones, etc....perhaps an amplifier?30 Ball BGAMARKING:Code:Y158239PE0The only thing I could find so far is some random thing on Alibaba - but with no real data on what it is.https://www.aliexpress.com/item/5pcs-lot-Chord-ic-Ringtones-amplification-ic-Y158-30-pin/32512065497.htmlAnyone have an idea on this one?

author: abraxa
author_rank: Frequent Contributor
timestamp: November 05, 2018, 11:06:26 am
content: http://download.yamaha.com/api/asset/file/?language=ja&site=jp.yamaha.com&asset_id=46254Seems like a good match, what you think?

author: amyk
author_rank: Super Contributor
timestamp: November 05, 2018, 12:56:47 pm
content: Looks like it:http://www.eric1688.com/product.aspx?id=393425

author: rx8pilot
author_rank: Super Contributor
timestamp: November 05, 2018, 05:27:52 pm
content: Quote from: abraxa on November 05, 2018, 11:06:26 amIt appears to be....I traced a number of the pins - SDA, SCL, GND, etc and they match other parts on the board.Curious how you found this? What did you search for? Perhaps a part family you are already familiar with?

author: abraxa
author_rank: Frequent Contributor
timestamp: November 05, 2018, 09:50:32 pm
content: I searched for "Y158 amplifier", came across the URL amyk posted, figured it could be a YDA158 and googling "YDA158 amplifier" gave the URL to the data sheet.
Anyone with experience using TI's BQ27220 Fuel gauge ? - Page 1
Forum section: electronics / projects

author: cgroen
author_rank: Unknown
timestamp: January 23, 2017, 06:43:04 pm
content: I know this is maybe a long shot, but with all the knowhow on this forum I thought....I'm about to use the Texas Instruments BQ27220 Fuel gauge in a project. It's a portable unit using a single cell LiIon (around 1300 mA/H) capacity. Device will be charged by USB.Do you have any experience using this device, I'm especially interested in how precise it is, are there any pitfalls etc ?Link to the little guy:http://www.ti.com/product/BQ27220

author: krho
author_rank: Regular Contributor
timestamp: January 24, 2017, 05:40:55 pm
content: This one looks even more complicated than STC311X series from STM

author: diyaudio
author_rank: Frequent Contributor
timestamp: January 24, 2017, 06:22:16 pm
content: Quote from: cgroen on January 23, 2017, 06:43:04 pmThey good and very accurate I have a EVM board and tested it you have to have a discharged battery in order for the learning algorithm to perform its function.

author: ace1903
author_rank: Regular Contributor
timestamp: January 24, 2017, 06:24:51 pm
content: I have experience with BQ27421 and on first sight looks similar to this one.BQ27421 has great spec but ti documentation is confusing, particularly part regarding learning cycle.I ended reverse engineering their tools, how they are performing learning process.Once done that documentation become clear and easy to understand.There are some pitfalls like to end learning cycle discharge battery with something like 1A and mine device consumed 200mA max and that required hw modifications on prototype.At the end product was perfect but at expense of many hours spent on SW driver development.

author: cgroen
author_rank: Unknown
timestamp: January 25, 2017, 07:35:58 am
content: Quote from: ace1903 on January 24, 2017, 06:24:51 pmI'm not sure I understand the "1 Amp" requirement ? Is that for teaching the system one single time, or is that needed for every device you produce ??

author: ace1903
author_rank: Regular Contributor
timestamp: January 25, 2017, 07:49:41 am
content: I put 1A as an rough number. It wasn't exactly 1A in practice but I don't remember exact number.Chip needs specific curvature of dv/dt of battery which can be achieved only with large current.You can make calibration using TI tools or in-city. Second case is more precise.BQ27421 has built in sense resistor and yours chip has external one maybe that makes difference.You need to perform learning cycle once and to prepare golden image from that.

author: cgroen
author_rank: Unknown
timestamp: January 25, 2017, 09:46:45 am
content: Quote from: ace1903 on January 25, 2017, 07:49:41 amThanks,makes sense! I will report back here once I get the first prototypes in a couple of months, will be an interesting experienceThe charger is a ADP5062 which probably will be even more interesting, around a zillion registers to configure in that one
Anyone working with Pelco D and/or DMX for sepecial designs? - Page 1
Forum section: electronics / projects

author: Synergy Hub
author_rank: Newbie
timestamp: October 10, 2013, 09:09:19 am
content: We have been looking at existing protocols to see what we can "weggie" into one and expand it for several special projects in the planning stages. So far it looks like our best bet is a hybrid of Pelco D and DMX sprinkled liberally with I2C and Arduino / Cypress PSoC4. Anyone else digging around in these areas ?
Anywhere I can get this LCD? - Page 1
Forum section: electronics / projects

author: orbiter
author_rank: Frequent Contributor
timestamp: September 09, 2013, 03:07:36 pm
content: Hi all,Is there a particular name/type for this LCD please? I've searched for the numbers etc but can't spot anything. I'm after picking one up but can't even find one?It's from a Roberts DAB radio that I'm repairing.Thanks all.

author: Andy Watson
author_rank: Super Contributor
timestamp: September 09, 2013, 03:26:59 pm
content: Have you tried contacting Roberts Radios directly? As far as I know, they still produce radios in the UK.

author: orbiter
author_rank: Frequent Contributor
timestamp: September 09, 2013, 03:28:35 pm
content: Quote from: Andy Watson on September 09, 2013, 03:26:59 pmYes, still waiting for them to get back to me.
AoE 3e - Single-supply JFET common-source amplifiers - Page 1
Forum section: electronics / projects

author: todorp
author_rank: Regular Contributor
timestamp: October 03, 2020, 10:32:04 am
content: Hi, I am trying to understand how the JFET amplifiers in the attached figure work.Idss for the BF862 is given as min = 10mA, max = 25mA.gm @ Idss is given as 45mS.I understand how the gain is calculated but there is one thing that is bothering me in particular: what kind of input swing do these amplifiers support?A. - Am I correct in supposing that for A. the input is allowed to swing only between -Vp (pinchoff volatge) and 0 (i.e. only 'negative' signal of 'small' amplitude)?B. - The input signal can swing from -Vp to somewhere below 0.4V? (0.4V would be Vs quiescent).Given this how does one go about designing (biasing) FET amplifiers that can amplify say a sinusoid centered at 0V of amplitude > +-2V ?Thanks a lot,Todor

author: Kleinstein
author_rank: Super Contributor
timestamp: October 03, 2020, 02:48:17 pm
content: The JFET needs something like 2 V source drain voltage as the lower limit to work at the relatively high current. The input range is limited by clipping at the output. So with a gain of some 13 in case A. This could be some 8/13 V (around 600 mV) for the input, but not linear over the full range. Which DC level is suitable depends on the FET and resistor choice and thus the output for zero input. There is no problem to also include small positive voltages, up to some 300 mV, when the gate gets more and more conducting.So it depends on the individual fets. It could be some -700mV to -100 mV or also some 0 mV to +300 mV (limited by gate conduction). This is a general problem with the relatively large variation in gate cut off voltage.Case B is similar, the exact range can vary quite a bit. -Vp is the lower limit, but not fixed. The upper limit is possibly also sightly more positive then the 0.4 V.

author: todorp
author_rank: Regular Contributor
timestamp: October 05, 2020, 07:01:21 am
content: @Kleistein - thanks a lot for the answer, everything is clearer to me now. I will try to breadboard these circuits and measure various parameters.Thanks again,Todor
AoE photodiode boostrap - Page 1
Forum section: electronics / projects

author: nihial
author_rank: Regular Contributor
timestamp: July 29, 2020, 05:18:44 pm
content: In the AoE in the photodiode section there's a circuit where a photodiode is bootstrapped by a jfet. It is mention in the text that there is a emitter follower not shown for simplicity but I don't understand where you put it. I'm trying to upgrade a frontend of a photodiode stage I'd like to test the circuit with that mentioned emitter follower especially if it improves the overall circuit.Thanks in advance !

author: PartialDischarge
author_rank: Super Contributor
timestamp: July 29, 2020, 05:39:55 pm
content: Turn to the next page and there you have your emitter follower in 8.83!

author: David Hess
author_rank: Super Contributor
timestamp: July 30, 2020, 02:23:05 am
content: Adding an emitter follower in series with the source of an FET is done because the transconductance of the FET is so much lower.

author: nihial
author_rank: Regular Contributor
timestamp: July 30, 2020, 06:59:28 pm
content: Quote from: MasterTech on July 29, 2020, 05:39:55 pmOh my god I feel so dumb to not have seen it

author: nihial
author_rank: Regular Contributor
timestamp: July 30, 2020, 07:00:19 pm
content: Quote from: David Hess on July 30, 2020, 02:23:05 amThank you for the explanation

author: David Hess
author_rank: Super Contributor
timestamp: July 31, 2020, 01:53:10 am
content: Quote from: nihial on July 30, 2020, 07:00:19 pmI should have also said that it is very common circuit configuration when you want an FET source follower to have a gain close to 1 and the ability to drive any significant load resistance. The impedance buffer for oscilloscope inputs and active probes almost always uses the same configuration.An alternative with better performance at low frequencies is the FET equivalent of a Sziklai pair with the input transistor replaced with an FET. Local feedback keeps the gain closer to 1:https://en.wikipedia.org/wiki/Complementary_feedback_pair
AOYUE 8800 Desoldering Gun Electronics - Page 1
Forum section: electronics / projects

author: delta-9
author_rank: Newbie
timestamp: December 10, 2016, 04:27:17 pm
content: PCB Components listBT134-600E Thyristor TRIAC 600V 4A TO-126LM358P DIP-8MOC3021 Random-Phase Optoisolators Triac Driver Output DIP-6DB107 DIP 1A 1000V Rectifier BridgeDB3 ST trigger diodey2 250v x1 400v ceramic capacitor100uF 16v Capacitor46E 104J CBB capacitorb203 potentiometer 20k3362 potentiometer 10k3362 potentiometer 500k1N4007 DiodeFR107 Diode20k Ohms 1%390k Ohms 1%240k Ohms 1%1.5k Ohms 1%8.2k Ohms 1%15k Ohms 1%2.7k Ohms 1%100 Ohms 1%470 Ohms 1%I'm going to make a second 3d printed desoldering unit, based on the aoyue 8800. Using replacement C088 element/barrel/nozzle.From what I can see, It looks like a two sided pcb. There is one small via bridging top and bottom trace.all components are through hole.I have enough parts to make 20 control boards, What I need is a duplicate of the original pcb in cadeagle. But have no experience with pcb designCan anybody help me create a schematic.Thankyou

author: amyk
author_rank: Super Contributor
timestamp: December 10, 2016, 05:37:55 pm
content: If you're looking to just clone the board, there's really no need to make a schematic.
AOZ Power ICs - Page 1
Forum section: electronics / projects

author: itdontgo
author_rank: Regular Contributor
timestamp: June 25, 2014, 01:05:35 pm
content: And I quote "Easy to use application software which helps to design and simulate the compensation loop can be found atwww.aosmd.com"It may be easy to use but easy to find? I don't think so. Has anyone ever used this software?

author: itdontgo
author_rank: Regular Contributor
timestamp: June 25, 2014, 01:08:26 pm
content: You know what I'm a dunce. It's right here:http://www.aosmd.com/media/EZBuck_ver2_1.xls

author: itdontgo
author_rank: Regular Contributor
timestamp: June 25, 2014, 01:08:53 pm
content: It's just a spreadsheet
AP1158ADS USB Power Filtering - Page 1
Forum section: electronics / projects

author: geo_leeman
author_rank: Regular Contributor
timestamp: November 02, 2018, 03:56:05 pm
content: Looking at the discussion here (https://electronics.stackexchange.com/questions/398132/usb-power-cleaning/398152) on USB power filtering I see the interesting AP1158ADS capacitance multiplier part. I've got a design using USB power to a +/- 5VDC DC-DC converter that then goes to some +/-3.3 VDC linear regulators to help get the cleanest possible analog rails. This is already a rather high BOM line item board, so this filter module looks great! Does anyone know of a similar P/N for cleaning up the negative rail? I've looked to no avail and really don't want to implement it from scratch if possible. Putting this before the DC-DC converter would seem pointless, yes?
APA102C RGB LED Panel system - Page 1
Forum section: electronics / projects

author: adammhaile
author_rank: Contributor
timestamp: April 28, 2017, 02:03:19 pm
content: Not sure if it is appropriate to post Crowdsupply campaign details here, but maybe someone might like this.We designed a APA102C based 8x8 matrix panel system which can be used to quickly build up large matrices with no (or minimal) soldering. The panels themselves have 3mm mounting holes which also act as electrical connections for +5V, GND, Clock and Data. Using the Bus board accessory, the matrix can be made arbitrarily larger. The bus board also has provision for mounting an Adafruit Feather M0, or an external controller can be used. Multiple bus boards can be stacked to make larger displays.The project is designed in KiCad and is Open Hardware.Github repository is here :https://github.com/wyolum/ultim8x8and Project details on our Hackaday IO page at :https://hackaday.io/project/21430-ultim8x8PS: We're also doing a begathon on Crowd Supply so please help spread the word :https://www.crowdsupply.com/maniacal-labs-wyolum/ultim8x8
APC SMT1500 Low Battery Shutdown DC Voltage Level - Page 1
Forum section: electronics / projects

author: mtnzap73
author_rank: Contributor
timestamp: September 19, 2023, 03:10:17 am
content: Is there any info existing that indicates the shutdown point for an APC UPS, SMT1500. In volts. Not minutes.My Powersonic AGM cells indicate a discharged voltage of 1.94 V per cell = 23.28 VDC. I can find zero info on what APC considers a discharged voltage level.I have taken a SMT1500 unit down to 24.06 VDC at the battery terminals, and the remaining battery level shows 24% and stays there.My runtime is not accurate as I have a 55 Ah batt (not the 18 AH stock one); it was calibrated but that is still a rough estimate. So, I can only watch the voltage and wait.I know I could just redo the test and stick with it until it shuts down, but I didn't really want to stress my new batts again yet.
APC SMT1500 Smart-UPS fan question. [Solved] - Page 1
Forum section: electronics / projects

author: vgamesx1
author_rank: Newbie
timestamp: August 27, 2018, 06:06:55 pm
content: I got a good deal on an older 2010 model SMT1500 for $50 but I didn't know that the fan always ran on these models, the fan isn't too bad it just borderlines on the side of being irritating, so can anyone here confirm what fan these things use so I can replace it or can you recommend a circuit to build my own fan controller? I've googled and couldn't find much of anything for my model and obviously I could look for myself but I already have it setup/running and do I really want to move then open a 35lb UPS + batteries if I don't have to? I'd really rather not.Also I kinda wanted to mention APC's awful "technical" support chat for a moment.Support: Unfortunately, I don'tr have the information as its an internal part and its not recommended to replace the fan. Only part that you can replace in this unit is the internal battery. No other internal parts can be replaced.I know a lot of companies are like this but that just boils my blood, to ask a simple question and meet a responses like that or the typical copy/paste ones... I mean not having the information is fine but don't tell me the only replaceable part is the battery, especially when the fan is by far the easiest internal component to replace.

author: vgamesx1
author_rank: Newbie
timestamp: August 28, 2018, 08:45:55 pm
content: Alright well since I couldn't find answers anywhere I finally decided to look for myself, for anyone else looking wondering what fan is inside, it's an 80mm 24v 0.1A fan, the exact model number is FD248025HS-N.
APC UPS magnetizing current and standby power.  SMT1500 - Page 1
Forum section: electronics / projects

author: bdunham7
author_rank: Super Contributor
timestamp: May 11, 2023, 08:46:39 pm
content: I'm renovating some UPS APCs, including this SMT1500 1.5kVA/1kW sine-wave model. It was working except the batteries were bad. I reprogrammed it for a slightly lower float voltage and then I wanted to see how that affected standby power consumption since a similar model that was in an enclosed cabinet was getting warm and had expanded batteries. So when it was all done, I measured the power and current after it was fully settled in and I'm not sure I can explain why it is doing what it is doing.The SMT1500, like most of these block-shaped sine-wave SmartUPS models, uses a large-ish EI transformer with a nominal 24VAC secondary and a 120V input with two extra taps at ~110 and 130V. It uses these for buck/boost during slightly low or high voltage--they call this "AVR trim". It also uses a MOSFET H-bridge to drive the transformer during backup operation and the same MOSFETs as an active bridge rectifier for normal operation.I set up a current clamp with a scope, a Kill-A-Watt monitor on the input and a DMM on the output. No load was attached. With the batteries fully charged, turning on the UPS and letting it settle results in a power reading of ~14W, a current reading of 0.65A and a VA reading of ~77VA. VIN= VOUT= ~120V +/- 2V. Battery charge current is pretty low, <5mA. This seems pretty much as expected, with 0.65A a reasonable magnetizing current for a pretty big transformer, a few watts lost to copper and iron losses in the transformer and a few more to run the UPS controls and fan. I was considering putting a capacitor across the transformer to reduce the overall reactive current. This probably isn't necessary since 0.65A isn't much recirculating current, but it wouldn't hurt to reduce it, right?However, after sitting there doing nothing for an hour or so, there is a 'click' sound and I see the power reading drop to ~8W (good) but the current goes to 0.95A. The input and output voltages are still nominal and identical. The only reasonable explanation for this AFAIK is that the UPS is switching both the input and output to the 'shorter' tap on the transformer. The question is...why? What does this accomplish? And does the input power dropbecauseit does this or are there just two things going on at once?Any ideas? Scope shots of input current are attached, both before and after the transition. I included AVG(64) and ERES(3.0) traces to show that the higher-frequency components are not just noise.
Apollo-Era Digital Logic - Page 1
Forum section: electronics / projects

author: wholder
author_rank: Regular Contributor
timestamp: January 21, 2015, 03:37:10 am
content: I've been experimenting with some of the very first Fairchild, "micrologic" series, integrated circuits. These are the same type of ICs used to build some versions of the Apollo Guidance Computer (AGC.) I was able to located a few uL923 parts, which are documented as JK Flip Flips, and get them working as a ripple counter. The AGC is said to have been built entirely using dual, triple NOR gates in flat packs, but I have been unable to locate similar parts on the surplus market. So, I settled for using the uL923 which, while in the same family as the ICs used in the AGC, are packaged in expoy-based, TO-99 configuration. If you're interested, I've written a short article with a demo video which you can see here:https://sites.google.com/site/wayneholder/apollo-era-digital-logicThese early fairchild RTL ICs were used as the basis of quite a few projects in the old American hobbyist magazine "Popular Electronics". For example, Don Lancaster's "IC-67 Metal Detector" on page 41 of the the January, 1967 Issue (http://www.americanradiohistory.com/Archive-Poptronics/60s/67/Pop-1967-01.pdf) was based on the uL914, which is a dual, two input NOR gate that's very similar to the parts used to build the AGC. Lancaster even managed to use these "digital" ICs as analog devices in the receiver portion of the metal detector.Wayne

author: coppice
author_rank: Super Contributor
timestamp: January 21, 2015, 03:49:51 am
content: Oh, that takes me back. I learned digital design by experimenting with Motorola MC7xx series RTL devices. I think the MC7xx series was the first time a group of ICs really formed a coherent family. Motorola had a separate MC8xx series of DTL devices. The Fairchild uL9xx devices were a mixture of RTL and DTL (maybe even TTL), which were not mutually compatible. There was no clear sense of devices families with these. Although these devices were available in TO99 packages, for high reliability applications, most were supplied in DIL packages looking exactly like the ones you can buy today.

author: wholder
author_rank: Regular Contributor
timestamp: January 21, 2015, 04:05:38 am
content: I remember the MC7xx series well, too. I believe it was used in a lot of PopTronics projects, as well.WayneQuote from: coppice on January 21, 2015, 03:49:51 am
Apollo Instrument Panel Lighting? - Page 1
Forum section: electronics / projects

author: petersanch
author_rank: Regular Contributor
timestamp: July 30, 2020, 08:56:16 am
content: The instrument panels in Apollo had words and lines back lit next to all the buttons. Any one know how they did this in the 1960s?

author: duak
author_rank: Super Contributor
timestamp: July 30, 2020, 03:47:37 pm
content: Well, one can learn something new every day. It's apparently Electroluminescent (EL) backlit as perhttps://www.hq.nasa.gov/alsj/tnD7290Lighting.pdfI wonder if the lettering was legible with the EL panels off, important in Apollo 13 when they were trying to minimize power consumption.

author: sokoloff
author_rank: Super Contributor
timestamp: July 30, 2020, 05:24:29 pm
content: Many aircraft have EL panels today. The labels are white when unlit and plainly visible/legible in pretty much any kind of lighting where you’d be performing a cockpit task.

author: jh15
author_rank: Frequent Contributor
timestamp: July 30, 2020, 09:39:56 pm
content: Fran tried hard to duplicate it, I think with some museum help. Gave up when someone else got it 'close enough'.I was fascinated since around 6 yrs old with the round greenish wall plug night lights. Lasting long enough till I was taking it apart years later and trying to figure how the plug conductor was bonded to the phosphor.still watching phosphor today: Panasonic ZT60 plasma tv.

author: texaspyro
author_rank: Super Contributor
timestamp: August 01, 2020, 07:21:27 am
content: BTW, if you change the drive frequency of those EL wall plug nightlights, the color changes.

author: petersanch
author_rank: Regular Contributor
timestamp: August 01, 2020, 08:29:36 am
content: Fascinating. Curious how they light up just the letters if EL panels come in square or rectangle shapes? Do they paint over everything except the letters?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 01, 2020, 08:39:46 am
content: Easy. Cut up the squares into letter forms, and wire a switch to each individual letter. Address the switches from a computer bus and there's your control.Easier said than done, natch...I forget offhand the exact tech used in the originals, but Ben of Applied Science (on YT) has made faithful reproductions using modern inks (transparent, EL and conductive, in that order) with screen printing. Not the cheapest materials, but eminently doable!Tim
app for notes management - Page 1
Forum section: electronics / projects

author: mrkev
author_rank: Regular Contributor
timestamp: April 30, 2018, 09:11:40 am
content: Hi, I was wondering, what do you use for management of notes on your projects. I was used to use just paper, but that quickly becomes messy and you don't have the search option. Now I am sort of pusshed to write it all in Word, but that is becoming messy and clouded too.Is there any popular program that could reliably manage notes (+pictures, graphs, etc.), preferably with some time stamp on each entry.

author: BravoV
author_rank: Super Contributor
timestamp: April 30, 2018, 09:13:56 am
content: Actually Word is quite good for annotations, revision and etc.Heavily used in legal as there are always tons of revisions, when, why, by who and etc.

author: mrkev
author_rank: Regular Contributor
timestamp: April 30, 2018, 11:11:45 am
content: I dont know, maybe I use the wront typology or something. All of those notes are mine, so I don't need to keep information about source, just the time stamp.

author: jeremy
author_rank: Super Contributor
timestamp: April 30, 2018, 11:25:13 am
content: I use Evernote. If you are just writing text and a few pics, the free plan would probably be fine for you.I stash all my data sheets of interesting/useful chips and hard to find documents in there because it can text search PDFs, but that is a paid only feature.

author: ebastler
author_rank: Super Contributor
timestamp: April 30, 2018, 11:59:46 am
content: If you use MS Office anyway, OneNote is not bad for this. A simple editor with just enough formatting options for my taste; if you paste stuff from a website it will add an annotation indicating the source; and it has multiple hierarchy levels for sorting your pages ("books", chapters and page tabs).

author: Bassman59
author_rank: Super Contributor
timestamp: April 30, 2018, 09:14:04 pm
content: Quote from: jeremy on April 30, 2018, 11:25:13 amMy wife bought a paid subscription to Evernote, and I am starting to use it for what you say above. datasheets, notes, notebook scribbles, anything project related which doesn't fit well in the Subversion repository.Like any of these systems, it requires discipline to use and a good idea about how you want to organize yourself.
App note inductor size - Page 1
Forum section: electronics / projects

author: paul23
author_rank: Regular Contributor
timestamp: July 30, 2013, 02:07:58 pm
content: I have found an app note (I think someone linked to it on here for somebody else) for an AVR single phase power meter. The app note itself is very good and does a good job of explaining things. However, in the BOM they haven't listed the value of inductor L50, which is on the schematic (see attached) and don't mention it in the app note. How to I work out what the value should be? I assume it is just there to filter out any noise between the analogue and digital supplies?I have modified the circuit a bit from the original. I have used a transformer to isolate and step down the voltage, rather than transformerless design Atmel use. I have also added a couple of extra ranges on the gain switches and done away with the counter and anti-tamper stuff, I don´t need that. So I am just reading the voltage/current on the live.the attached image is Atmel´s original design from app note AVR465

author: wraper
author_rank: Unknown
timestamp: July 30, 2013, 02:17:48 pm
content: It can be something like 10uH, yes it's for noise filtering.

author: paul23
author_rank: Regular Contributor
timestamp: July 30, 2013, 06:41:38 pm
content: Thanks, that´s what I thought

author: c4757p
author_rank: Super Contributor
timestamp: July 30, 2013, 07:14:05 pm
content: Aack!! What a sloppy schematic! Kind of puts me in the mood for spaghetti...

author: CarlG
author_rank: Regular Contributor
timestamp: July 30, 2013, 07:30:28 pm
content: My guess is that they suggest to put in a ferrite bead there, perhaps not that critical. You'll probably get some 2x mains switching noise on Vcc that you should try to get rid of, and maybe hf noise from the uC that needs to be filtered out.I my schematics I use specific bead symbols, and indicate the impedance at 100 MHz just to have a clue.

author: c4757p
author_rank: Super Contributor
timestamp: July 30, 2013, 07:48:18 pm
content: Actually, IIRC, many of the AVR datasheets recommend a plain 10uH inductor.

author: Unknown
author_rank: Unknown
timestamp: July 30, 2013, 07:52:36 pm
content: What would the advantage of a plain inductor over a ferrite bead be in this application? Is a higher Q really an advantage for wide-band filtering like this?
Apple Smart Connector Experience?   - Page 1
Forum section: electronics / projects

author: bugrobotics
author_rank: Regular Contributor
timestamp: February 14, 2019, 03:30:52 pm
content: I have a client looking to implement the Apple Smart Connector system used on the IPad Pro 11 (pic below shows the three contact pads). I haven't dealt with this interface and was looking for some feedback regarding the protocol and hardware required from others who may have messed with the connector. Thanks!

author: tooki
author_rank: Super Contributor
timestamp: February 14, 2019, 05:11:43 pm
content: I’d be curious, too, but I doubt you’ll get much info, because it’s only released to developers under an NDA. :/

author: bugrobotics
author_rank: Regular Contributor
timestamp: February 14, 2019, 08:29:46 pm
content: Yeah, I'm currently requesting info from Apple. Can't wait to hear the reply.

author: amyk
author_rank: Super Contributor
timestamp: February 15, 2019, 01:19:58 am
content: Reverse-engineer it yourself and forget about any NDAs

author: tsman
author_rank: Frequent Contributor
timestamp: February 15, 2019, 01:50:30 am
content: Reverse engineering it may be difficult as it is nearly certain that you need a special Apple MFi authentication chip in your device.If your client really wants use that connector then they'll have to go through the headache of getting approved + paying for MFi membership.

author: bugrobotics
author_rank: Regular Contributor
timestamp: February 15, 2019, 03:29:47 am
content: Quote from: tsman on February 15, 2019, 01:50:30 amThanks, this is what I read about and why I was asking. I've started the process with Apple and will update the thread with any info.

author: dopsin
author_rank: Newbie
timestamp: February 28, 2021, 08:41:31 pm
content: @bugrobotics,Did you succeed in getting tech doc for the smart connector?I'm planning to perform MFI process. Any tips in communication with Apple?Thanks in advance

author: mon2
author_rank: Frequent Contributor
timestamp: March 02, 2021, 11:04:34 pm
content: Here is what Apple will tell you..." "Low level technical details from Apple?MFI is not what you may think. The MFI program will allow limited access to source / sell authorized components that the factory will audit. It is meant to maintain quality control and to protect their bottom line.We are working with MFI certified factories in Asia. Apple is very tight on what can and cannot be produced for their widgets. Only if Apple grants their blessing can the MFI licensed ODM build the product on our behalf.As an example, lightning male to male cable is not allowed by their set rules. The sale of the handshake IC inside the magsafe2 hoods is not to be resold as a component, etc.
Application of wireless data acquisition monitoring and control - Page 1
Forum section: electronics / projects

author: Adom
author_rank: Newbie
timestamp: October 16, 2015, 04:39:22 pm
content: Hello everyone,Can anyone give me a specific idea for implementing a project based on "wireless data acquisition, monitoring and control"? I'm thinking of a simple wireless sensor network and a device that could be controlled by a relay with LCD monitoring all done wirelessly (something that can be designed with a microcontroller).

author: Jeroen3
author_rank: Super Contributor
timestamp: October 16, 2015, 07:57:05 pm
content: Quote from: Adom on October 16, 2015, 04:39:22 pmWireless networks are not simple, but you can use zigbee, or maybe wifi. (with those dirt cheap new wifi modules)LCD's are not simple, but you can use Segger EMWin, or Nextion.The overall idea is that these projects look simple on the outside, but require significant time and effort to develop. Not to talk you down of course, but rather send you to explore parts to integrate.

author: kkessler
author_rank: Regular Contributor
timestamp: October 16, 2015, 08:12:19 pm
content: The cheap wifi modules are ESP8266, but they are not well documented and probably better if you have experience with some other systems. The Particle Photon are more expensive, but have a nice Arduino like development system around them. Wifi is power hungry, though, so if you are looking to battery power the sensors, the nRF24L01 modules are cheap and paired with a low powered uC, could make a nice remote sensor.

author: Jeroen3
author_rank: Super Contributor
timestamp: October 17, 2015, 11:34:38 am
content: I have one of thoseSparkParticle Cores. These would be perfect to get going fast with IoT stuff. Assuming you want IoT?Their cloud api can makes things significantly easier to interface to a LCD using an raspberry pi or smartphone app.

author: kripton2035
author_rank: Super Contributor
timestamp: October 17, 2015, 12:28:11 pm
content: ESP8266 are now programmed with an arduino IDEso they are as simple as an arduino, and almost everything works as an arduino ( exceptions see here :https://github.com/esp8266/Arduino)you can plug an i2c LCD module to it (the esp8266 don't have a lot of I/O so i2c or SPI is often used)and you will talk to the lcd like you would do it with an arduino, it's really not that complex.

author: Adom
author_rank: Newbie
timestamp: October 17, 2015, 12:29:16 pm
content: Thanks guys but I was thinking of implementing the LCD using the microchip applications library with one of those mikromedia boards from mikroe.com, and also using an nRF24L01+ rf transceiver or zigbee. My main problem is I want a specific application in order to demonstrate the need for such a system
Approach for IoT project - Page 1
Forum section: electronics / projects

author: Red_Micro
author_rank: Regular Contributor
timestamp: February 11, 2020, 05:50:13 am
content: Hello,I'm getting into the world of IoT. I want to start a project where I'd like to automate some current sources. Basically I would have a CT measuring source output current into the device under test (DUT). This is the process:1. Scan DUT and current source ID and send it to some database. I would like to have a GUI to enter some parameters and also send it to the database.2. Start DUT test. Measure current source output and send the current data to database for graphic and calculations purposes.Basically I'm just looking for potential suggestions on IoT protocols, database, GUIs, and microcontroller for CT measurement. I'm trying to define an ecosystem.I would appreciate any suggestions from people experienced in IoT.

author: mayor
author_rank: Regular Contributor
timestamp: February 13, 2020, 11:51:34 am
content: I'm building my own ecosystem around the TI CC1352 chip using their 15.4 stack. Essentially uc/radio daughterboards that hook up to whatever sensor/controller, etc, you have. The collector runs on a linux system (in this instance a Raspberry Pi), running a React front-end. I don't do this professionally, but happy to discuss. FWIW.
appropriate method to test DAC? - Page 1
Forum section: electronics / projects

author: SArepairman
author_rank: Frequent Contributor
timestamp: April 08, 2014, 06:10:38 pm
content: Is it appropriate to test the linearity of a DACs LSB by putting say 5V ref into the DAC and then summing the output of the DAC with a negative DC signal to bring down the DC by a known amount so that a more high resolution range on the multimeter could be used for categorizing the step size?At your meters 100mV full scale you get a much better idea of what is going on then on the 10V full scale, so I'd rather measures (4.9-4.85=0.05) 50mV volts on the 100mV then 4.9 volts on the 10V range.I feel with a precision op-amp, a foil offset adjustment pot (or stable wire wound) and some good negative reference would make this method pretty useful and not noisy.is this a method commonly used with source meters?**could be a use for the precision adjustable resistance standards that dave jones compelled me to buy.it seems like a difficult method for exact measurement but it should allow a precise categorization of step size, even without precision addition adjustment because the process is additive.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 08, 2014, 07:02:46 pm
content: I would think a dynamic process would be better. Generate a linear count, highpass filter it and amplify the error. If it's perfectly smooth, each step should be visible with the same difference. The steps will contribute an overall high frequency spikiness, harmonics of the sample rate. Errors will show up as sidebands of the spikes, but mostly as lower frequency rumble. If the harmonics are filtered out, the RMS noise remaining should very much resemble the DNL (also RMS). Note that DNL is usually periodic with hiccups around certain code transitions; this will look like every Nth sample spike being taller than usual.Tim

author: SArepairman
author_rank: Frequent Contributor
timestamp: April 08, 2014, 07:20:01 pm
content: What do you mean by dynamic process?Measuring the voltage with an op amp network/dac configured to track the input voltage so that the net voltage is never outside of bounds for the lowest multimeter range?How could you set that up? ADC/MCU to adjust a DAC? I don't get what you mean by high pass filtering, I am thinking about DC measurements.How about using two dacs to "comb out" error?

author: edavid
author_rank: Super Contributor
timestamp: April 08, 2014, 08:17:09 pm
content: Analog Devices has published a lot of good material on this, e.g.http://www.analog.com/library/analogdialogue/archives/39-06/Chapter%205%20Testing%20Converters%20F.pdf

author: David Hess
author_rank: Super Contributor
timestamp: April 08, 2014, 09:57:20 pm
content: How much resolution are you dealing with? The simple way to test static DAC linearity is to sum the output with a better DAC or use an ADC to measure it directly. Alternatively I might use harmonic distortion measurement of a low frequency sine wave as a proxy for linearity.
Arachne-pnr: an open-source place and route tool for Lattice iCE40 FPGAs - Page 1
Forum section: electronics / projects

author: mian2zi3
author_rank: Contributor
timestamp: May 28, 2015, 07:04:35 am
content: I wrote an open-source place and route tool, arachne-pnr, for the Lattice iCE40LP/HX1K FPGA, building on the awesome work by Clifford Wolf and Mathias Lasser of the IceStorm project reverse engineering Lattice iCE40 FPGAs:https://github.com/cseed/arachne-pnrhttp://www.clifford.at/icestorm/Support for the 8K is on the way. Along with Yosys, the open synthesis suite, this gives a fully open-source Verilog-to-bistream FPGA development tool.http://www.clifford.at/yosys/The design is pretty straightforward. It uses simulated annealing for placement and has a congestion-based multi-pass router with A* search. The main missing feature is timing-driven routing, which I plan to add once IceStorm documents the chip timing.I'd love to target other chips if anyone wants to reverse engineer them. :-)edit: typo.

author: clifford
author_rank: Regular Contributor
timestamp: May 28, 2015, 10:45:47 am
content: I made a video demonstrating the flow:

author: nctnico
author_rank: Super Contributor
timestamp: May 28, 2015, 11:17:17 am
content: No VHDL support?

author: mian2zi3
author_rank: Contributor
timestamp: June 01, 2015, 03:25:19 am
content: Quote from: nctnico on May 28, 2015, 11:17:17 amSynthesis is done through Yosys. I thought Clifford would chime in since he wrote that. Yosys only has native Verilog support, but it does have support to read VHDL by calling through to vhdl2verilog. I refer you to the documentation for the Yosys vhdl2verilog command:http://www.clifford.at/yosys/cmd_vhdl2verilog.htmlIf someone wanted to contribute a native VHDL frontend, I'm sure he'd be thrilled.

author: free_electron
author_rank: Super Contributor
timestamp: June 01, 2015, 02:30:01 pm
content: just out of curiosity : why ? ( because we can, or, out of curiosity , are valid answers )why go through all the trouble trying to roll your own synthesizer and mapper.anyway, looks like lattice have sprouted a whole family of interesting devices. some in qfn some in 16 ball bga's with relatively large gate counts , at low prices ( atarting at 1.5$ per piece ) time ot take another look at these...
Arbitrary wavefrom generator design - Page 1
Forum section: electronics / projects

author: elektronchika
author_rank: Contributor
timestamp: June 27, 2014, 12:09:38 pm
content: Hello,a signal generator is very useful tool. As I'm interested in the topic I decided to develop my own. A think to use Digilent Nexys 3 board (Spartan 6 FPGA) for the DDS. Actually, I have the dds design running, using a DIY board with TI DAC904, connected to 2 of PMod connectors. The sample rate is 100Msps.Next steps are to make amplitude and offset control, output ON/OFF. Am looking for a few MHz bandwidth (up to 10 is good enough for me, and 5Vpp amplitude with +/-2.5V offset control). I decided to use TI DAC5862 dual DAC for amplitude and offset control. One of the dacs will control DAC904 reference voltage, the other one will generate offset. Some op-amp and the schematic is done. I have a few questions concerning the design:- The Nexys 3 board has 4 PMod connector. But due to impedance matching, is it good idea to use them for 100Msps signals? the board also has VHDCI connector with 20 LVDS pairs. But is needs at least 3 or 4 layers board to route all the pins. And I'm not sure is there pairs can be used as single ended (DAC904 has parallel CMOS interface).- DAC904 accepts reference voltage from 100mV to 1,25V. So I need post amplification/attenuation of -20dB, 0dB and +20dB in order to be able to have output signals as low and 10mVpp and as high to 10Vpp. What output stage circuit will you suggest me: TI VCA820 with another dac for gain control; simple op amps circuits, which are switches with 5V relays; another VGA/PGA or something else?- Are high speed op-amps with output disable suitable for output ON/OFF function or small relay is better? I've heard some relays ticking on and off in standard waveform generator when changing amplitude, offset, output on/off, so I suggest the relays are the best choice?- Some other advises you have?Regards!

author: mathias
author_rank: Regular Contributor
timestamp: July 02, 2014, 09:48:13 am
content: You can try to use the PMod connector, making sure that your clock arrives late enough with respect to the data. That way, possible ringing can die out.
arc fault interrupt circuit topology - Page 1
Forum section: electronics / projects

author: sarepairman2
author_rank: Frequent Contributor
timestamp: February 15, 2016, 08:04:54 pm
content: how do arc fault interrupt protectors work (like the ones you see for circuit breakers) and are there products/reason to include them on a PCB ?Low current AFI modules to put inside chassis? AFI asic ?seems impractical to implement.it would be cool to have a little thing to put on PCBs in addition to MOVs and shit O0

author: sarepairman2
author_rank: Frequent Contributor
timestamp: February 15, 2016, 08:14:02 pm
content: explanation video

author: sarepairman2
author_rank: Frequent Contributor
timestamp: February 15, 2016, 08:27:35 pm
content: high pass filter + integrator + chop circuit + comparator a good way to do it on a chip>?
Architecture Design Software - Page 1
Forum section: electronics / projects

author: Mark
author_rank: Frequent Contributor
timestamp: October 17, 2020, 05:23:29 pm
content: Hi all,I am looking for a graphical software package that will allow an architecture, either hardware or software, to be designedat a very high leveland shared with others.Ideally: something that is viewable without installing a huge software package (does pdf allow this?).It will allow entry of block diagrams and signal flow paths, and every block should be clickable to delve deeper into the hierarchy.It will be easy for an engineer to distribute to management types so that they can navigate through the architecture to understand what is going on.Is there a software package you would recommend for this purpose?Thank you.

author: MosherIV
author_rank: Super Contributor
timestamp: October 17, 2020, 09:52:34 pm
content: Are you familiar with Unified Modelling Language (UML) ?It is the standard design and modelling language used for software development.Look for UML software.

author: cdev
author_rank: Super Contributor
timestamp: October 18, 2020, 12:57:47 am
content: Dia?There are also UML modeling packages, There are lots of different approaches to data modeling and lots of kinds of desired output. Dia is primarily a program to give you graphical output but you also can generate code with some of its add ons.If you want a nice database design package I like pgmodeler.

author: ebclr
author_rank: Super Contributor
timestamp: October 18, 2020, 09:40:31 am
content: https://www.smartdraw.com/
Archive low power consumption and losses 1v8 or 3v3 - Page 1
Forum section: electronics / projects

author: Yaroooo
author_rank: Regular Contributor
timestamp: November 09, 2022, 01:42:31 pm
content: Hello Guys,I'd like to make a smart button (iot) with a small battery 120mAh 3.7v LiPo , avg. power consumption of 2mAh . I'd like to optimize power supply and found that all components can be powered by 1V8 instead of 3V3 power rails.Leaving out single components power consumption, LDOs (using LP2985) efficiency will drop. Would a switching regulator improve my efficiency or the gain would be negligible? Just looking if effort to switch to 1V8 from 3v3 brings advantage.

author: tszaboo
author_rank: Super Contributor
timestamp: November 09, 2022, 04:24:53 pm
content: Your microcontroller will have reduced current consumption at the reduced voltage. Going from 3.3V to 1.8V with typical 90%+ efficiencies already going to save a lot, and then this effect is on top of it. Select a switching converter wit h low quiescent current.But you can save probably order of magnitude more with your code, and part selection. For such a "mostly sleeping button with some RF" you can probably go down to 20uA easily.
Arcnet on Raspberry Pi - Page 1
Forum section: electronics / projects

author: sarason
author_rank: Contributor
timestamp: February 12, 2024, 02:39:19 pm
content: I am looking to build a project on Raspberry Pi. An interface for Arcnet to talk to a Juki 700 series SMT machine.Has anyone worked with this before, know of any projects that have ported the Juki Software to Raspberry Pi or anothersmall computer. Any Arcnet open source implementation?sarason
Arctic grade stranded Cat6 patch cables - Page 1
Forum section: electronics / projects

author: perdrix
author_rank: Frequent Contributor
timestamp: January 21, 2023, 09:39:45 pm
content: I've been trying to find a 2m or 3m Cat6 stranded patch cable that will remain flexible at low temperatures (IOW Arctic grade).So far no success.Does anyone have good source?ThanksDavid

author: TheMG
author_rank: Frequent Contributor
timestamp: January 22, 2023, 01:54:21 am
content: If I remember correctly, the stuff we use at work is Belden 7931A. It'll bend without breaking even at -40C or colder (yes, we do get these temperatures where I live several times per winter).Note that at room temperature this stuff is not as flexible as standard CAT6 cable, but the main thing is it is still somewhat flexible in extreme cold temps and most importantly can be handled and bent without damage.I haven't seen pre-made patch cables using this type of cable or similar, so you'll most likely have to make your own, but that's not hard to do.

author: perdrix
author_rank: Frequent Contributor
timestamp: January 22, 2023, 06:59:31 am
content: The catch is of course that I don't want to spring for a 305m drumDavid

author: Electro Detective
author_rank: Super Contributor
timestamp: January 22, 2023, 08:44:38 am
content: I would also be concerned about the plastic connectors and device sockets going brittle or suss contact at such temperaturesand the soldering/solder supporting them= good luck with that