hybridfree/eevblog-posts huggingface dataset:
Agilent/Keysight Visual Engineering Environment (VEE) Software - Page 1
Forum section: electronics / projects

author: cncjerry
author_rank: Unknown
timestamp: February 02, 2020, 03:17:46 am
content: I just became aware of this software when I was looking at Pete Millett's code for the HP 8903A Distortion Analyzer. The runtime version is free but I was having a hard time finding a version for Win10. But in looking at the software, it looked sort of cool and I thought I would ask here if anyone knows of a way to get the development version for low-cost? Home version? student? Extended trial? etc.It looks like they have a run-time version for Wiin10 and I can always setup a VM for other windows versions having legitimate boot code for just about all of them. If not, I'll stick with Visual Studio for my engineering code.Thanks,Jerry

author: chuckb
author_rank: Frequent Contributor
timestamp: February 02, 2020, 02:31:16 pm
content: I've been using HP VEE for over 20 years. I now have version 9.3 and it works just fine with Win 7 and Win 10.I believe there is a 30 day free trial version.I understand that Lab View has a low cost (free?) version for Makers.

author: graybeard
author_rank: Frequent Contributor
timestamp: February 02, 2020, 09:20:36 pm
content: We have been using VEE for years where I work, but are transitioning to LabView because support for VEE is being discontinued by Keysight. Their market share has been shrinking and is no longer big enough for economic viability. LabView won.Unless you have to use VEE you should pass.Besides LabView some small companies I have worked with use MatLab as their test software.I would use LabView because it has the best support.

author: cncjerry
author_rank: Unknown
timestamp: February 03, 2020, 08:40:06 am
content: Thanks for the replies. VEE looked interesting and that is why I asked. I've written LabView (have the home edition) and found it difficult for some reason even though I've been programming for 45yrs. I use Visual Studio C# or VB coupled with MS Access and find it easy to use for GPIB interface projects. There are some features lacking for graphical charting that LabView does better but other than that, It does what I need. The VEE code was written by Pete Millet for driving an HP 8903 and it looked interesting.ThanksJerry
AGM battery charge characteristics as a solar bank.   - Page 1
Forum section: electronics / projects

author: viper
author_rank: Regular Contributor
timestamp: January 13, 2024, 02:25:02 am
content: I was poking around and found some really good info from some of you guys and figured a great place to discuss. I actually dabble in solar stuff but never really had the perfect strategy for battery banks because people live in this perfect world where you bulk charge, reach boost charge levels, then float. In reality, there is always some variable demand which can bounce bank voltages around, making it tough to get right.I am using my own RV bank for example here. I have 5, 200ah, 12V AGMs. They are actually designed to be UPS radio tower batteries. OEM does not really rate them for what I am doing. Generally it takes most of a day to get voltage levels beyond 14V so I have controller just set to run to 14.4V. I understand that they should be disconnected at .01C or reduced to float, but things like a heater blower will come on and drop that back in the 13s. For instance, as I am looking at it now, I was at 6A charge level, 14.4V, which is fully charged, or should be. But I know the sun will be gone in 1hr or some load will kick on and pull that back within 30min.Anyone have a good strategy that is both safe for the batteries, and doesn't undercharge them?The float V from the OEM is actually 13.6, not 13.8 for some reason, but recommends occasional boost charge at 14.4 for no more than 24hrs.....? I mean, normally there is no way to get there. At most, maybe 3hrs, but I always have concerns.Thoughts? I don't really think the OEM wants to say anything other than "these are UPS batts", but are most certainly deep cycle.
AGX Orin Carrier Board - MIPI CSI Lane Length Matching - Page 1
Forum section: electronics / projects

author: electronx
author_rank: Regular Contributor
timestamp: April 04, 2025, 09:33:06 am
content: Hello,I am designing a carrier board for AGX Orin and have some questions regarding MIPI CSI length matching.For example, for CSI 0:CSI_0_D0_P / CSI_0_D0_NCSI_0_CLK_P / CSI_0_CLK_NCSI_0_D1_P / CSI_0_D1_NI match all these lanes within themselves.Similarly, for CSI 1:CSI_1_D0_P / CSI_1_D0_NCSI_1_CLK_P / CSI_1_CLK_NCSI_1_D1_P / CSI_1_D1_NI match all these lanes within themselves.When analyzing the reference design's trace lengths, I noticed the following grouping:CSI0 is matched with CSI1CSI2 is matched with CSI3CSI4 is matched with CSI5CSI6 is matched with CSI7In this case, do I also need to match the lengths between different CSI groups, such as CSI0 and CSI1?Or should each CSI group only be matched internally?Thanks.

author: electronx
author_rank: Regular Contributor
timestamp: April 07, 2025, 10:16:30 am
content: No idea?

author: Hydron
author_rank: Super Contributor
timestamp: April 07, 2025, 04:03:36 pm
content: Reference design has the MIPI setup as 4 links each of 4 channels wide (I think also with the extra clocks still available so that it can be used as more narrower links). When done like this (rather than in 2 wide links) then the length matching needs to be done as you've seen. While NV docs can be rather shit sometimes, there's enough there on their portal to understand it all. If you don't have portal access then good luck though!

author: fchk
author_rank: Frequent Contributor
timestamp: April 07, 2025, 05:42:17 pm
content: Quote from: electronx on April 04, 2025, 09:33:06 amIt depends. You can use CSI(n) and CSI(n+1) independently as two separate two-lane interfaces.Or you can combine CSI(n) and CSI(n+1) to form a four-lane interface. CSI(n+1).CLK isn't used then.If you construct 4-lane interfaces all 4 lanes plus clock must be length-matched.I'd recommend to use 4 lane interfaces and the 22-pin connector. You already have 4 4-lane interfaces.
AHPF opamp input voltage protection with clamp diodes sinking source - Page 1
Forum section: electronics / projects

author: electronx
author_rank: Regular Contributor
timestamp: January 04, 2024, 12:50:14 pm
content: I am designing an iepe signal conditioner and as seen in the introduction I have a 2nd order butterworth high pass filter..When the sensor (load) is not connected, the current source with 24 V supply with 4mA constant current will completely turn on the MOSFET and the output will be 24 volts (xtr111 output will not give exactly 24 volts, it will give a value of approximately 21.6V), but let's assume that there is a 24V input.-----------------------------------------------------------------------------------------------------------------------------If we look at the OPA192 datasheet, the entry values in the Absolute Maximum Ratings section are limited as follows. Since we are supplying (V–) – 0.5 and (V+) + 0.5+15V )(-15V ), -15.5 and 15.5 are the maximum limits we can apply to the inputs.-----------------------------------------------------------------------------------------------------------------------------If we focus on transient analysis, when the 24V input signal comes, the current will pass through the clamp diode (BAT64) through the 2k limiting resistor and go to the +15 line. The simulation is here.Accordingly, the 15V power supply will need to sink a value such as 3.315mA. I use a UWE1215S-3WR3 supply that can output +-15 V to feed the opamp. However, I am not sure how much source sinking it can do, maybe it does not do it at all.graph of the +15 volt sourceu can see the +15v source is sinking You can see that it is sinking for up to 20ms.Briefly, how can I protect the inputs of the opamp when we apply 24v? Do I need to add a 15V zener diode reverse connected to the power rails for sinking?I don't want the opamp to burn out when there is no load.If you notice any other errors in the circuit, please let me know.

author: dobsonr741
author_rank: Frequent Contributor
timestamp: January 04, 2024, 03:48:23 pm
content: What is the normal, not disconnected, range of the input? Might want to put a TVS diode on the input before the first capacitor. A better protection then letting the transient go deep into your circuit.If the supply rail lifting concern still exists after that, model the power supply as well. The Mornsun presumably have an LDO inside, will not prevent lifting. The load current and the rail bypass capacitors will limit the lifting, specially as it is a transient only. Might add another TVS after the capacitors and before the opamp. The Zener on the rail should be the last resort IMO, as it will not prevent just limit the lift. Thus allow other parts to be impacted on the same rail.
AI A6 Ceullar module. Problem with UART? - Page 1
Forum section: electronics / projects

author: mrpackethead
author_rank: Super Contributor
timestamp: January 08, 2018, 07:49:17 pm
content: I coud'tn help myself but to buy a couple of AI A6 Cellular modules the other day when i was buying some 'real' parts from a supplier.. Given they are so cheap. I have installed a valid Sim into it.I plugged it in last night, on a 3.3V TTL serial adaptor.. Serial port is set for 115200, 8bits, No parity, 1 stop bit.I've had a couple of lines of text come back saying "CINIT 2, 32, 41891" etc etc But not relaibly, it doe'snt do it all the time, just sometimesI try to send a AT command, but nothign returns.. Its almost like the device is not getting my commands.I've checked my Serial interface, by plugging in a loopback and it seems to be working ok.Does anyone know if the TTL interface shojudl be 3.3V or 5V? I've got two of them, and they are both doing the same thing. I dont' have a 5V TTL interface, so not sure if i need one.EDIT. i tested the Serail interface on a beaglebone black just for good measure. It works without any issues. So either i have some kidn of level incompatblity, or theres some other issue.
air circuit design - Page 1
Forum section: electronics / projects

author: krayvonk
author_rank: Regular Contributor
timestamp: September 27, 2019, 04:44:31 pm
content: Trying my hand at design, its not fully finished yet, but its gone through a fair bit of scanning.Its pneumatic logic, not electrical, all untested, just thought it looked nice, its a pneumatic muscle driver for an air-bot.Ive got the whole brain to go nextAll method is done, But Ive got the whole bingo machine to go next, how many pages will it be? Maybe 500... ive really got to get my work cut out for myself.
air condition gsm control - Page 1
Forum section: electronics / projects

author: singera
author_rank: Contributor
timestamp: October 19, 2012, 08:07:40 pm
content: hey to all, I want to design gsm controller for mtstsubishi air con,I try to record the remote to the computer and to the arduino, but the word its so long that it cant repeat it using an ir-blaster (I sucseed control my tv set), so I took after market remote and connected wires to the TPs that connected to the buttons and than connect this to relays that controlled with arduino.may be some try to record with arduino air con codes an sucsseed?ThanksArnon

author: SeanB
author_rank: Super Contributor
timestamp: October 20, 2012, 06:01:16 am
content: What do you want to control? If only on off then hack apart a remote control.
Air conditioner control, important parameters - Page 1
Forum section: electronics / projects

author: CambridgeMart
author_rank: Regular Contributor
timestamp: June 23, 2019, 09:40:34 pm
content: As another project, I bought a faulty air conditioner that needs a new control board; of course, the board isn't available, so I need to brew my own. I've managed to decode the remote signals and know what controls are required for the fans, my remaining task is to monitor the temperatures; the output temp from the evaporator is easy as it's basically the setpoint (this unit doesn't have a remote thermostat), but there's a thermistor on the compressor discharge pipe and I don't know what temperature this should be at. My research tells me the highest temperature is the critical temperature for the refrigerant, 96.7C for R290 in this unit and the lowest temperature must be above the highest ambient temperature for the condenser to operate. What I'm after is guidance as to what end of this range I want to be aiming for.
Air cooled connector - or just a weird design? - Page 1
Forum section: electronics / projects

author: compet17
author_rank: Regular Contributor
timestamp: August 17, 2015, 06:44:56 pm
content: I disassembled this HP (Compaq) power supply and found that strange arrangement of cooling fins that seem to have no other purpose as cooling the PCB itself... But it is so close to the gold edge connector that I assume it is there to keep the contact fingers cool.Any other ideas??? Someone seen that before?Unfortunately I don't know the electrical specs. Only that it takes about 700W from the mains and spurts out 5VDC and 12VDC for a disk array. Most power is most likely on the 12VDC rail.

author: Maxlor
author_rank: Frequent Contributor
timestamp: August 17, 2015, 07:38:36 pm
content: Looks to me like they expected their ground return to carry enough current to heat up that connector significantly. It's not just the cooling fins, that's also a lot of quite wide traces.

author: electr_peter
author_rank: Unknown
timestamp: August 17, 2015, 07:43:49 pm
content: My guess is that those fins serve a purpose of adding extra cooling capacity (thermal mass + surface area + air movement) so that actual PCB connector does not heat up and fail. Thermal runaway is very common failure for a high current carrying connectorsresistance is higher on the connection than on the wire. Resistance can be high due to debris, oxidation or loose connection as wellhigher resistance leads to temperature increase in connectionhigher temperature degrades (oxidizes) metal at faster rateresistance increasestemperature rises at accelerated rate...thermal runaway -> destruction of connectorThis happens with automotive and other high power connectors all the time. See this thread for an examplehttps://www.eevblog.com/forum/beginners/what-is-going-on-here/I think extra cooling capacity may stop thermal runaway or at least reduce it to non critical levels. Most connections on PCB are doubled as well - if one fails, the is another.

author: jonjoy1999
author_rank: Newbie
timestamp: August 17, 2015, 08:37:23 pm
content: It's to cool down the flow of electrons as they pass through the card to the connector resulting in higher electron density and more power on the other side of the interconnect.

author: compet17
author_rank: Regular Contributor
timestamp: August 18, 2015, 05:19:32 pm
content: An Electron intercooler..... hmmm. Nice idea
AirGradient OSS/OSH Air quality multi-sensor.  PMSx003 woos. - Page 1
Forum section: electronics / projects

author: paulca
author_rank: Super Contributor
timestamp: March 28, 2024, 05:54:09 pm
content: I bought one of these from the states, in a (shamefully lazy) soldered, partly assembled kit form.https://www.airgradient.com/indoor/Out of the box it worked, but pestered for being registered with it's cloud. I did note that all particulate mater values where 0.I flashed it with ESPHome based firmware and it works even better now without no cloud... and MQTT data, command and control ala HomeAssistant style API.Still however there are 0s and "NaN" values for the PM sensor.I provoked it by lighting some cardboard on fire, then blowing it out and holding it directly under the sensor. (CO2 and VoC went nuts)... PM sensor read 0.What I need to prove next is ... is that sensor duff or the combination of customizations on already 3rd party firmware.I have two options.Software: Add logging debug probes to the various layers ESPHome, PSMx driver, UART LL. Possibly even to the extent of running it in an Eclipse IDF with a JTag debugger...Hardware: Solder 2 probe leads onto the Rx/Tx of the sensor and read it on the scope.I'm thinking the later is a far better use of my Saturday morning.Anyone any experiences with these?

author: jmw
author_rank: Frequent Contributor
timestamp: March 28, 2024, 11:20:28 pm
content: I made my own AQ monitor using a sensor that was a rebadge of the Plantower sensor that those devices use. By default they just chatter their readings over the 3.3 V TTL level UART pins. The data format is simple,https://aqicn.org/air/sensor/spec/pms5003-english-v2.3.pdf. If you have USB-UART interface, you can read the raw data frames in a terminal viewer.They're susceptible to an early death if the fans pull debris into the measuring chamber ... in my case, probably cat hair. They just permanently read the max reading for me. That's probably why the PurpleAir monitors have redundant sensors, mounted with the fans pointing down so things don't settle in.

author: airgradient_achim
author_rank: Newbie
timestamp: March 29, 2024, 11:46:37 am
content: Achim, founder of AirGradient here. Thank you for buying our kit and supporting our open source hardware air quality project!We recently had a few cases where it appears that the PM sensors got damaged during transportation.I would like to send you a new one. Could you please send me a message through the support form on our website with a link to this forum so that we can arrange the shipment of the spare part?Many thanks!

author: airgradient_achim
author_rank: Newbie
timestamp: March 29, 2024, 11:49:38 am
content: We had mostly problems with insects getting into the plantower. What helps for maintenance is to blow compressed air from time to time through the sensor to flush out these kinds of things. We have deployed thousands of these monitors and typically they last quite long.
Airless solder paste dispencer - Page 1
Forum section: electronics / projects

author: apoorv3in
author_rank: Contributor
timestamp: August 03, 2022, 09:29:25 am
content: My attempt at making a solder paste dispenser.This uses a N20 motor and AS5600 magnetic encoder to create a closed loop setup.Have tried making it as small as possible, with my limited skill.This is unfinished project and will require further development. It takes power from a single stereo jack which also acts as an input port for connecting a external pedal switch, This port will eliminate the need for additional wire for external trigger switchI am integrating a display in this as after testing it. I see a need to tweak multiple parameters. Without a screen it becomes difficult to do so.

author: thm_w
author_rank: Super Contributor
timestamp: August 03, 2022, 09:05:03 pm
content: Nice work.Yeah you might want some adjustable retraction motion to pull the solder paste back so it doesn't drip.

author: apoorv3in
author_rank: Contributor
timestamp: August 04, 2022, 12:51:30 am
content: From this initial design what I observed is 3 paramaters have to be adjusted.1. Forward distance2. Retraction distance3. Speed of forward and retractionAlso the solder paste syringe, piston are designed such that it becomes defficult to grab them with some mechanism to enable effective retraction. There are syringes where pistons have thread, but these are only available from the manufacturer of such dispensing solution

author: markhen
author_rank: Regular Contributor
timestamp: August 05, 2022, 05:03:56 pm
content: I’m starting a similar project - your design looks very elegant and compact! Looking forward to seeing your future enhancements !
Aishi electrolytics - Page 1
Forum section: electronics / projects

author: jitter
author_rank: Frequent Contributor
timestamp: September 03, 2016, 07:50:24 pm
content: Why is it that Aishi is a brand that seems to fly mostly under the radar?The brand is not the most well known in electrolytic capacitor land, maybe even mostly unknown. However, they seem to be a popular choice in stuff from the lighting industry.I have torn down quite a few failed CFLs that had bulging caps (among which was a Rubycon of a suitable type for that application) but never any from Aishi's.I just tore down a LED bulb with over 25,000 hours on it, and the Aishi cap inside measured just fine. I recently had a peek inside a semi-pro LED-driver and found them inside there too...They hardly seem to be available from suppliers over here. So, why don't we see more of them?

author: wraper
author_rank: Unknown
timestamp: September 03, 2016, 09:32:20 pm
content: They are used in some of the Delta computer PSUs. Also they are widely available from local distributors here for some reason (probably they get them from TME). And yes they are widely used in CFL bulbs and other lighting applications.

author: jitter
author_rank: Frequent Contributor
timestamp: September 04, 2016, 05:14:05 am
content: I have yet to see them in anything non lighting related. Yes, I saw that TME sells them, but it seems to be only one type.If price were a consideration, I'd happily choose them over the well known Japanese brands given my experience with them so far.Apparently they rank no. 1 in China and no. 10 worldwide on sales volume. You'd certainly think they'd be a bit better well known than they are.Sometimes I wonder how deserved reputations actually are, surely by now the capacitor plague is something of the past.And to be honest, the only caps I saw fail prematurely were those green sleeved, gold printed ones from makes that, everytime you tear something down, has changed to something else (just google the series "CD288L" and wonder how many brand names it's sold under). Typically found in low cost wall warts or bargain basement LED-bulbs.One thing I often notice on these: for some reason they print the word "VENT" on them, as if it's a novel feature.To me that always means that it will be VENTing very very soon...I have recently been modifying some CC LED-drivers from a (semi-)pro luminaire that I want to be a fit and forget item for at least a decade to come. Had there been one of those dodgy brands in there, I'd certainly have replaced them with something better. But as they were from Aishi, I felt comfortable to leave them in there (and no, I have no personal gain whatsoever promoting Aishi capacitors, in case you were wondering).But again, in my book Aishi has started getting a reputation like (e.g.) Mean Well, Chinese of origin, but of good quality.
AK4493 in oct/hex mode - oversampling filter bug? - Page 1
Forum section: electronics / projects

author: phofman
author_rank: Newbie
timestamp: May 16, 2021, 05:09:59 pm
content: Hi,Please does anyone have a practical experience with AK4493 in oct or hex sampling speeds, i.e. 384+kHz sample rates?When MCLK is at least 128xFS and sampling speed (DFS0-2) at most quad, the DAC outputs correctly oversampled signal. When dropping MCLK to 96xFS and setting corresponding sampling speed to oct or hex, the DAC output waveform is broken.This is 96kHz sine generated at 384kHz. The chip officially supports MCLK 49MHz, hence I can set MCLK=128xFS and the corresponding quad sampling speed. The output waveform is flawless:and detail showing the oversampled steps:However, when using MCLK = 96xFS (correct ratio according to the datasheethttp://d.zaix.ru/5cHC.pdf) and the corresponding oct sampling speed, the DAC output waveform is broken:The same occurs for the hex sampling speed (e.g. at 768kHz or even at 384kHz with MCLK = 64xFS). I am surprised nobody would have noticed such a weird behavior, but have not found anything being discussed about this. Well I have not found any technical discussion of using these chips at fs > 192kHz (but they are used in commercial soundcards supporting up to 768kHz).Thank you very much for any hints and recommendations.Pavel.
Akai ADM80 Microphone To PC? - Page 1
Forum section: electronics / projects

author: mictas
author_rank: Regular Contributor
timestamp: November 03, 2016, 12:57:07 pm
content: I picked up one of these microphones yesterday would like to know if I can just plug one of these into a PC Mic in and have it work out of the box without any kind of a amplifier.Please see the attached photo, but the details I have found are...Dynamic Microphone, Non Directional, IMP 10KIt dose have what looks to be a mono 6.3 headphone jack, I am waiting on an adapter to 3.5 mm.

author: mictas
author_rank: Regular Contributor
timestamp: November 04, 2016, 06:58:51 am
content: Quote from: blueskull on November 03, 2016, 01:11:24 pmThanks for that, I am just waiting on the adapter to come in the post.

author: mictas
author_rank: Regular Contributor
timestamp: November 10, 2016, 04:57:48 am
content: Quote from: mictas on November 04, 2016, 06:58:51 amJust an update, the adapter came in the post and this Microphone works just fine, as is.Thanks for the comment.
AL5817, analog dimming - Page 1
Forum section: electronics / projects

author: Noir_47
author_rank: Newbie
timestamp: October 28, 2024, 11:26:49 am
content: Hello.Maybe someone has already used this chip and can give me some advice.I wrote to DIOEDES support, but I think that due to the non-critical importance of my question I will not receive an answer soon...Product page, where there is a datasheet and user manual for the evaluation board.DatasheetEVAL board user manualProduct brochure.Excerpt from the brochure:QuoteSome questions:1) Is it possible to dim using an analog signal via the VSET pin?2) I did not see a clear requirement for a current shunt in the datasheet. Can I use my 0.04 Ohm shunt if the strip consumes about 2.5 A and is powered by 12 V, which gives a 0.1 V voltage drop on the shunt at maximum load.3) Why is there a 1nF limitation on the capacitance between VSET and GND?Quote

author: PCB.Wiz
author_rank: Super Contributor
timestamp: October 28, 2024, 10:45:06 pm
content: Quote from: Noir_47 on October 28, 2024, 11:26:49 amLooks fine to me.Note they spec a 7mV max offset.Quote from: Noir_47 on October 28, 2024, 11:26:49 amIt will be a ground-capable opamp, so 100mV drop will be ok, but keep an eye on that 7mV max offset which then becomes 7%Quote from: Noir_47 on October 28, 2024, 11:26:49 amThat does seem strange. You could test one ?

author: Noir_47
author_rank: Newbie
timestamp: October 29, 2024, 01:40:27 am
content: Quote from: PCB.Wiz on October 28, 2024, 10:45:06 pmTo be honest, I think I somehow damaged the chip as a result of my careless actions...I ordered a pair of new ones, but they will arrive in a few weeks.Another thing that confused me about the datasheet was:Quote

author: PCB.Wiz
author_rank: Super Contributor
timestamp: October 29, 2024, 01:55:21 am
content: Quote from: Noir_47 on October 29, 2024, 01:40:27 amThat's just simple negative feedback.Such chips are designed to linear regulate, so they will have that bit right, and you do not need to worry too much about the descriptive words.

author: Noir_47
author_rank: Newbie
timestamp: October 29, 2024, 02:46:10 am
content: @PCB.WizThank you for the tips. Will try to use them as soon as possible.
al8843 dc_dc regulator problems - Page 1
Forum section: electronics / projects

author: tlwEEVblog
author_rank: Newbie
timestamp: March 26, 2022, 01:57:59 am
content: Has anyone observed a power-up issue with the al8843 chip?We designed and are testing our own PCB design using the al8843 chip. The design is based on a modified version of the circuit recommended in the datasheet. We added a trim pot to the current sense resistor to allow us to easily adjust the current set point. We are NOT using the PWM control. We are using a lab power supply as the source. The circuit seems to be regulating as expected over a wide input voltage range and current set points. However we have observed that at under some current set points and supply voltages, when the power supply is turned on, the chip does not start correctly and the internal switch transistor is stuck in the ON condition (no switching). If we test the same circuit by disconnecting and re-connecting the cable from the supply, then it works properly. It seems that the rise-time of the power supply turning on is the issue. Like the chip wants to see a fast rise time on the supply input. I am considering using the CTRL pin to solve the issue, but haven't tried it yet. By putting a resistor- capacitor at the control pin to hold the switch OFF until the power supply has stabilized, much like a reset circuit on a microprocessor chip.
AL8843 LED Driver Problems - Page 1
Forum section: electronics / projects

author: will_raymo2000
author_rank: Newbie
timestamp: February 08, 2020, 10:15:26 pm
content: Hello,My aim is a 2A constant current LED driver for some grow lights for some chilli plants I'm growing this year. I selected the AL8843 chip (https://www.diodes.com/assets/Datasheets/AL8843.pdf) having had good experiences in the past with the AL8805.I followed the circuit in the data sheet and modelled my pcb on the schematic and layout of the evaluation board (https://www.diodes.com/assets/Evaluation-Boards/AL8843EV1-User-Guide.pdf).The LEDs I bought are XM-L2 chips from CREE (bought through RS so the real deal), having seen flashlight drivers driving them at 2A or more on tiny heatsinks I chose 2A for mine on a chunky aluminium heatsink profile.Assembled a pair of the drivers and thoroughly checked them for any shorts or solder bridges - all good. I am powering them from a 24V chassis mount Mean Well PSU capable of 5A. Configured the LEDs in 2 strings of 5 in series with one driver for each string. Assuming a forward voltage of ~3.1V per diode that worked out at 15.5V nominal output voltage. I punched those figures into the calculator provided by Diodes Inc which can be seen below.I connected up one driver with one string - got a flash then nothing. The full input voltage is presented at the output but the LEDs are only dimly lit with less than 2mA being drawn. Assumed too much current so removed one of the current sense resistors to make an output current of 1000mA but still no joy. It seems to have killed the first LED in the chain, on checking the rest of the LEDs they all illuminate on the diode test mode of my multimeter but I don't want to connect them again without knowing what caused it.Does anyone have any experience with what might be going on here? I have a multimeter but no scope unforunately so can't see whats going on at that level. I'm assuming a problem with my layout maybe but not sure. Theres no chance of the LEDs being over driven that quickly is there?EDIT: Just realised none of the parts showed up on the schematic so here goes;L1 - 68uH 2.1A SaturationC1 & C2 50V X7RC3 100nf 100V X7RC5 & C6 1uF 100V X7RR1 & R2 0R1 1%Diodes are all B360B-13-F as per the eval boardWiring between LEDs and supply wiring all in 25swg I think (although I havent got the label on it anymore )

author: stefanh
author_rank: Contributor
timestamp: February 11, 2020, 05:19:10 am
content: I think the capacitors are bit low in value for the rectifier.

author: will_raymo2000
author_rank: Newbie
timestamp: February 15, 2020, 04:53:51 pm
content: Turns out that the thermal pad clearance to the pins of the AL8843 were too close and had bridged without me seeing. So the LED string got a full blast of unregulated 24v - woops!Since being a bit more careful in assembly I have had 3 of these boards running 16 hours a day for a week without issue

author: tlwEEVblog
author_rank: Newbie
timestamp: March 11, 2022, 04:03:42 am
content: Hello- I saw your schematic and pcb and wondered if I could get a copy of each of the files?Thanks,Tim
AL8853AQ temperature - Page 1
Forum section: electronics / projects

author: NikWing
author_rank: Regular Contributor
timestamp: May 24, 2024, 02:08:06 pm
content: Hello all!after a long time of just lurking I'm back with a question about a LED driver IC from Diodes.Maybe anyone here has an idea if something is wrong or if I could ignore what I think is a problem:I've made me a small LED driver board to drive white SMD LEDs in series, using Diode's AL8853AQ IC, which uses an external MOSFET for switching.The circuit is basically the one found in the datasheet (figure 1: Typical Boost Schematic for Constant Current Output Application)It works, but I've noticed that the AL8853 is rather hot. Since it is not switching any load except the MOSFET gate, I wonder why it is hot and if this is a problem.I don't see any information about the working temperature in the datasheet, except for the junction temperature over-temp protection:QuoteDoes it mean the IC itself can get hot and I should not worry?btw, personal opinion: I hate that these drivers need an external enable signal to start working. Why can't they just make use of an undervoltage shutdown function like normal DC/DC-converter drivers have? A simple voltage divider between VIN and GND and a threshold level and it will start as soon as it gets power from a PSU ... all my LED driver ICs (like AP3041 and AL3066) have this problem :/Greetings,Nik

author: aliarifat794
author_rank: Regular Contributor
timestamp: May 24, 2024, 03:55:11 pm
content: AL8853AQ should be properly heatsinked or mounted on a PCB with sufficient thermal vias to dissipate heat. If the IC is operating within its specified junction temperature range (usually provided in the datasheet), then it's likely functioning as designed.

author: NikWing
author_rank: Regular Contributor
timestamp: May 24, 2024, 06:11:38 pm
content: yeah, it has no thermal pad at the bottom, so the only way is to do it via pin pads and groundplane, but usually there is some air gap below the chip SO8 case.it's just a little hard to understand for me why a chip that does not switch any current become this warm (up to 160°C junction temp), so I thought I ask here for opinions
alarm clock pcb - Page 1
Forum section: electronics / projects

author: gatoazul
author_rank: Contributor
timestamp: November 27, 2016, 10:24:01 am
content: Hi,can someone help design a pcb from this schematic and post the gerber and pdf files?Thanks for the help.

author: jonovid
author_rank: Super Contributor
timestamp: November 27, 2016, 11:02:35 am
content: https://www.aliexpress.com/item/Smart-Electronics-4digit-Digital-LED-Clock-Kit-Light-Control-Temperature-Display-LED-Digital-Clock-DIY-Kit/32596690389.html?spm=2114.01010208.3.213.AKNIL4&ws_ab_test=searchweb0_0,searchweb201602_4_10065_10068_9886_10000007_10084_10083_10080_10082_10081_10060_10061_10062_10056_10055_10054_10059_10099_10078_10079_10073_10097_10100_10096_10070_10052_10050_10051_424,searchweb201603_9&btsid=15c7a228-e655-43e9-8b12-c10d897d7113Dun! and their is still time to reinvent the wheel

author: JoeN
author_rank: Frequent Contributor
timestamp: November 27, 2016, 11:22:08 am
content: http://www.ebay.com/itm/4-digit-LED-Digital-Electronic-Clock-DIY-Kit-Light-Control-Transparent-Case-W8V4-/351668128939Neat. I am going to buy a few of these for Christmas to give to kids I know who like to build stuff like this. This is the perfect level of construction, not too difficult but not ass simple.

author: void_error
author_rank: Frequent Contributor
timestamp: November 27, 2016, 11:29:04 am
content: Quote from: gatoazul on November 27, 2016, 10:24:01 amWhy would you want to build something with an ancient microcontroller in the first place?

author: gatoazul
author_rank: Contributor
timestamp: November 27, 2016, 11:31:03 am
content: i need the circuit for the pic 16f84 that i have to test and learn programming Pic in basic.

author: JoeN
author_rank: Frequent Contributor
timestamp: November 27, 2016, 11:33:13 am
content: Quote from: gatoazul on November 27, 2016, 11:31:03 amThat doesn't require a PCB. You could have this wired up from parts and a perf board in an hour to two and it would work perfectly well and ready for programming. A lot faster than waiting for a professional PCB to be delivered.
Alarm Keypad Protocol - Page 1
Forum section: electronics / projects

author: ludzinc
author_rank: Unknown
timestamp: September 16, 2015, 11:11:58 am
content: HiI'm wanting to integrate with my home alarm panel as a part of my home automation hobby, and I figured the neatest way would be to mimic the keypad.The connection to the panel is a 3 wire interface, two being power and ground and the third being 'data'. The keypad is a Vertex series like the one in the link here:https://goalarmshop.com.au/hills-burglar-alarms/reliance-alarm-keypads/security-keypad-led-16-zoneI've scoped the data pin (briefly) and the first hurdle is that the alarm panel seems to be running from -12V with respect to my house's earth. Hooking up the scores ground cleip to the 'common' input on the keypad shorted the rail and all the blinkenlights stopped. Thankfully all the magic smoke was kept inside and by referencing the keypads positive terminal with the scope I managed to get the attached pics.My goole-fu isn't that strong on this topic, and I was hoping that some one could point me in the right direction. Does this look like a typical keypad interface (I found many references to the 4-wire DSC system) or am I entering into unknown territory? Anyone out there ever worked for Hills before and can elaborate?Thanks in advance,SimonPS - Apologies if I've managed to post twice on this subject, my earlier attempt today doesn't seem to have made it (from my view).Links to pics:

author: Muttley Snickers
author_rank: Unknown
timestamp: September 16, 2015, 12:38:44 pm
content: It's a Hills NX series made by Caddx and they are very popular, I dont understand what you are trying to do as devices on the lan bus are individually addressed, in addition certain information in regards to security systems is a bit tricky when it comes to disclosure on a public forum even though there are plenty of them around, Austech for instance.Your keypad is a 16 zone so your panel is most likely a NX-16.*94-Program Code-Keypad Address ( 1 to 8 ) - * - Area Number.Also your service light is trying to tell you something, press *2 and read the number.It will be low battery, system clock or somebody tampering with it that shouldn't be...
Alarm Project - Page 1
Forum section: electronics / projects

author: Jim95
author_rank: Contributor
timestamp: September 17, 2015, 10:11:16 am
content: Hello all,I have been designing a simple air flow alarm recently. It works by taking a signal from a pressure switch that closes when the pressure is above the desired threshold and opens when pressure drops bellow. The circuit I have designed will take the signal and alarm when the pressure is below. The user can then mute the alarm using the switch. The two LEDs are for either safe or fail.A few part names are wrong on the schematic:The voltage regulator is a L78L05The NPN BJT is a 2n3904The MCU is an ATTiny85This is the first circuit of this nature that I have design from scratch. Can anybody spot any mistakes that I've made in terms of how I've interfaced the MCU?

author: IanJ
author_rank: Unknown
timestamp: September 17, 2015, 10:41:04 am
content: Hi,Reconfigure the pressure switch input on the low side, i.e. run the 5v supply through a resistor and out to once side of the switch, then tie the other side of the switch to 0vdc (GND). That way, if there is any problem with the external cabling/wiring then you won't short out the 5v supply. It also helps to keep noise on the supply to a minimum by keeping it 'in the box'.Small cap on the pressure switch input to help against de-bounce.Add some protection on the supply input.Supply decoupling next to the processor.I'd also use a FET instead of the BJT personally.Ian.

author: Jim95
author_rank: Contributor
timestamp: September 21, 2015, 03:50:46 pm
content: Thanks for the reply.In terms of choosing a PSU for this circuit would it be good practise to use a 5v supply? Is there any need for the voltage regulator if I am doing this?

author: MatthewEveritt
author_rank: Unknown
timestamp: September 21, 2015, 04:48:43 pm
content: The reset pin is active low, so I'm guessing it probably shouldn't be tied to ground.

author: mij59
author_rank: Frequent Contributor
timestamp: September 21, 2015, 05:08:47 pm
content: Missing ground connection to IC1The resistor R5 is way to low, what kind of buzzer your using ?

author: Jim95
author_rank: Contributor
timestamp: September 22, 2015, 02:14:25 pm
content: Quote from: MatthewEveritt on September 21, 2015, 04:48:43 pmThanks, don't know why I had it wired like that.Quote from: mij59 on September 21, 2015, 05:08:47 pmCompletely missed the IC ground connectionI'm using this buzzerhttps://uk.rs-online.com/web/p/magnetic-buzzer-components/7542034100? seems to work quite well on the breadboard?

author: mij59
author_rank: Frequent Contributor
timestamp: September 22, 2015, 02:53:22 pm
content: Quote from: Jim95 on September 22, 2015, 02:14:25 pmThe pin output current of the ATTiny will be something like 30 to 40 mA, close to the maximum allowable output pin current, try to keep the pin current as low as possible, no need to fry the ATTiny.Very little information of the buzzer available, try for R5 a resistance of 470 to 1K Ohm and check the collector emitter voltage of T1 when turned on.Best solution is what IanJ suggested, a logic gate N-channel mosfet, e.g. 2N7000.
Aldi 2Ah & 4Ah LiPo Battery Packs - Page 1
Forum section: electronics / projects

author: DeanCording
author_rank: Contributor
timestamp: April 17, 2018, 03:11:11 am
content: Aldi have their 2Ah & 4Ah LiPo battery packs on sale this Saturday 21/4 for $29.99 and $39.99 respectively. Both battery packs are rated at 20V.The charger unit ($19.99) is easily gutted and modified to work as a power supply base.I bought these last year for use as a power source for a DPH3205 buck-boost power supply module.On the positive side:both packs use Samsung INR18650-20Q 2000mAh cells - 2Ah 5S - 4Ah 5S2P15A continuous discharge current for 2Ah pack30A continuous discharge current for 4Ah pack12.5-13V dropout voltageMeasured capacity reasonably close to rated capacity - 4Ah - 80Wh claimed but cells rated 72Wh - 65Wh measured at 5A drawReasonably slow voltage drop over discharge rangeOnboard battery charge and discharge protectionPercentage capacity remaining displayOn the not-so-positive side:Uses a generic microcontroller for the BMS so there is no way of telling exactly how it worksNo individual cell monitoring or balancing4Ah battery pack drops out at low discharge current drawsThe low current draw dropout behaviour of the 4Ah battery pack is strange. Below 350mA, the battery will shutdown after a couple of minutes and needs to be totally disconnected and reconnected to restart it. Between 1A and 350mA, the battery pack will dropout for about 200ms before restarting automatically. Above 1A there are no dropouts. The 2Ah battery pack doesn't exhibit this behaviour. I've sort of minimised the problem by stuffing a couple of 33000uF caps into a gutted charger base along with a couple of diodes and charge rate limiting resistor.

author: DeanCording
author_rank: Contributor
timestamp: April 17, 2018, 04:28:46 am
content: A 3d printed connector for these batteries is available fromhttps://www.thingiverse.com/thing:2770920

author: wilfred
author_rank: Super Contributor
timestamp: October 07, 2018, 10:54:56 am
content: I found some Aldi stores near me in Eastern Melbourne have these, 4Ah $30 and 2Ah $20 and chargers $15Forest Hill had several dozen.When does Aldi tend to reduce prices on clearance items?Although I don't know why they need to clear them if they regularly sell skins of various tools.
Alegbraic Inversion for Other Forum.. - Page 1
Forum section: electronics / projects

author: LaserSteve
author_rank: Super Contributor
timestamp: April 17, 2016, 01:04:02 am
content: I can't post pics in the other forum.. This is a Algebraic Inverter using Logs... From a old book I have... Will save other guy hours of working this out, I hope..Will pull the attachment after 48 hours per Educational Use Clause in US law.....Steve

author: onlooker
author_rank: Frequent Contributor
timestamp: April 17, 2016, 01:26:48 am
content: "Ir" should be marked next to pin 13 of the IC, instead of, next to pin 3 of A1.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 17, 2016, 09:52:01 am
content: Quote from: LaserSteve on April 17, 2016, 01:04:02 amNo worry, I'd say it's within Fair Use: it's only one page out of a whole book.Tim

author: Kalvin
author_rank: Super Contributor
timestamp: April 17, 2016, 02:19:40 pm
content: Quote from: T3sl4co1l on April 17, 2016, 09:52:01 amI agree. However it might also depend on where the server is located how the laws will be applied.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: April 18, 2016, 12:40:18 am
content: Quote from: Kalvin on April 17, 2016, 02:19:40 pmWould that be the Law of Logs?
Alfa semiconductors - Page 1
Forum section: electronics / projects

author: TimFox
author_rank: Super Contributor
timestamp: January 26, 2022, 07:59:36 pm
content: Is anyone familiar with "Alfa" or "Alfa Rpar", a semiconductor company from Riga, Latvia? I first saw them on the "new items" page of Antique Electronic Supply.They have some interesting devices aimed at audio and electronic music, including re-makes of obsolete parts and some interesting matched BJT devices (PNP and NPN).However, when I checked their website, Malwarebytes Browser Guard flagged the page as possibly containing trojan malware.

author: Benta
author_rank: Super Contributor
timestamp: January 26, 2022, 08:04:32 pm
content: I have no problem at all getting to their web site. Browser: Brave.

author: BrokenYugo
author_rank: Super Contributor
timestamp: January 26, 2022, 09:04:42 pm
content: Chrome (edit: fully updated) isn't flagging anything for me athttps://www.alfarzpp.lv

author: TimFox
author_rank: Super Contributor
timestamp: January 26, 2022, 09:54:58 pm
content: Is anyone familiar with the company, or has used their products?

author: bsw_m
author_rank: Frequent Contributor
timestamp: January 27, 2022, 01:49:58 am
content: I use their products in many places, but they are made in the times of the USSR. On it I can say one thing - high-quality and reliable components.Unfortunately, I have not yet been able to use their modern products.By the way, I compared the site in Russian and in English, they have different content."Russian site" google-translated:https://www-alfarzpp-lv.translate.goog/rus/sc/news.php?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=ru&_x_tr_pto=wapp

author: JPortici
author_rank: Super Contributor
timestamp: January 27, 2022, 06:41:27 am
content: They are quite known in the synth diy community (the application specific chips) with good reputationi have personally used their matched pairs

author: strawberry
author_rank: Super Contributor
timestamp: January 27, 2022, 07:20:17 am
content: bought some, quality is goodi bet the same happen for thepiratebaynot used any malware software for ~10yno lagging no updates no expensessome time ago sent arduino .asc or .exe ..file code via email and turned out I made trojan and file was deleted. to overcome problem change to .jpg and backrecently turns out some malware software mined coins on your hardware!!