hybridfree/eevblog-posts huggingface dataset:
Lcd 20x4 not working - Page 1
Forum section: electronics / beginners

author: franciscoPT
author_rank: Contributor
timestamp: February 04, 2021, 08:14:24 pm
content: Hi guys, im building a power supply with 2ch 0-30v 0-5A, i have bought 2 lcd 20x4 2 years ago and test them when they arrived and they were working properly, today i was going to use them for the power supply and when i tried the typical hello world program, they didnt write anything, im using the arduino to controll them, i start check for shorts, with multimeter, on the solder pins, and found pin 5 and 6 are shorted, not on the solder, probably internal short, i check the other lcd and same thing, is this the problem?? can someone with same lcd confirm this??? is there any reason for shorting this 2 pins while soldering, thinking on that i try to be very careful and quick.

author: madires
author_rank: Super Contributor
timestamp: February 04, 2021, 09:03:26 pm
content: Pin #5 is "R/W" and pin #6 "E". To send a command or data to the controller R/W is pulled down to indicate a write operation, and E needs a pulse to take in the command/data. A short between both pins would prevent the enable pulse, i.e. the display won't do anything. Is the short on the LCD module (desoldered/disconnected)?

author: retiredfeline
author_rank: Frequent Contributor
timestamp: February 04, 2021, 09:25:48 pm
content: The facts that they were working when received and that both units behave the same now, suggest some wiring error on your part.Are you for example identifying the pin numbers correctly? Maybe what you think is pin 1 isn't due to the way you have oriented the module.

author: franciscoPT
author_rank: Contributor
timestamp: February 04, 2021, 09:54:06 pm
content: Im shure pin 5 and 6 are shorted, but its strange that they are on both lcd, i dont understand why and the bigger problem its they are not in the solder like bridge on pins, there is internal short wich i probably cant fix, i think i kill my lcd....

author: rstofer
author_rank: Super Contributor
timestamp: February 05, 2021, 09:35:16 pm
content: Before I would pronounce the LCD as 'dead', I would try a standard Arduino Sketch that is known to work. Like:https://www.arduino.cc/en/Tutorial/LibraryExamples/HelloWorldIf you have already tried this kind of test then maybe the LCD is dead.
LCD basics help! - Page 1
Forum section: electronics / beginners

author: Quantumplate
author_rank: Regular Contributor
timestamp: April 18, 2025, 10:42:39 am
content: Trying to expand my knowledge of these beyond 'they run on a.c.'Looking at this portion of the data sheet for a upd833 clock chip/lcd driver, i don't understand how the voltage difference between the COMMON and Vsh (an lcd segment) is twice Vsh when a segment is lit. (left hand graphic) I make the difference only one unit of Vsh. The right side flatline makes sense when the display is blank. I get that.Also as the segment voltage is now double, 3v, with a 1.5v battery powering the chip/circuit, if someone wanted to replace the lcd screen would they specify a 1.5v lcd or a 3v one?Thanks

author: Quantumplate
author_rank: Regular Contributor
timestamp: April 18, 2025, 11:20:27 am
content: Ok, here's the screenshot

author: fchk
author_rank: Frequent Contributor
timestamp: April 18, 2025, 11:35:30 am
content: Quote from: Quantumplate on April 18, 2025, 10:42:39 amTheabsolutevalue in a clock phase is one unit. The real difference in plus one unit in one clock phase and minus one unit in the next clock phase. This gives two units between consecutive clock phases. It would be one unit if one of the signals would be constant.

author: Quantumplate
author_rank: Regular Contributor
timestamp: April 20, 2025, 09:40:56 pm
content: Quote from: fchk on April 18, 2025, 11:35:30 amThat was a very succinct but hard to initially grasp way of putting it.I've come up with the 'Two Hands Playing the Bongos' analogy.Works for me!
lcd bus - Page 1
Forum section: electronics / beginners

author: kars
author_rank: Contributor
timestamp: March 28, 2016, 01:29:44 pm
content: hi,i recentely found a lcd screen and want to use it but i cannot figure out what bus it is. can someone help me?the screen has fe following contacts: door, reset, clock, stb, data and 3.3v power and ground.hope someone can help me!

author: homebrew
author_rank: Frequent Contributor
timestamp: March 28, 2016, 05:53:25 pm
content: Door?could you please provide a photo? Would make things a lot easier ...

author: danadak
author_rank: Super Contributor
timestamp: March 28, 2016, 08:06:14 pm
content: Part number of the screen would be most helpful.Regards, Dana.

author: kars
author_rank: Contributor
timestamp: March 31, 2016, 01:48:10 pm
content: well... i already found out what door means...its from an old cd player and its a sensor wire to test if the door is open or not.so only data and stb need to be solved

author: kars
author_rank: Contributor
timestamp: March 31, 2016, 01:58:20 pm
content: oh bwt the chip on the control board is a A2495F but finding a datasheet isnt easy

author: mariush
author_rank: Super Contributor
timestamp: March 31, 2016, 02:20:01 pm
content: clock and data could be a pair for data transfer ,see i2c or spi (two-wire)stb could be stand-by , for example raise to 3.3v to enable or tie to ground to enable stand-by mode .. stand by could mean turn off backlight, and/or go into sleep mode but retain the data that's on lcd panel in the controller's memory.
LCD Controller Board DIY Kit(MT561-MD) NOT WORKING. - Page 1
Forum section: electronics / beginners

author: Evaldas
author_rank: Newbie
timestamp: January 30, 2020, 07:13:51 pm
content: Hello,So I bought this DIY kit from eBay a while ago. But it didn't come with an inverter so I had to buy it separately. I bought this Universal one from eBay. Not sure how safe it is but I was hoping it would work. So I put everything together and the screen backlight lights up and seems to work but I get no picture on the screen. It doesn't look broken (Cant find any cracks or anything).Does anyone know why that may be? Is it a broken screen or could the controller or the inverter be faulty.Thank you very much!

author: mladenitanja
author_rank: Newbie
timestamp: February 09, 2020, 05:51:25 pm
content: Does led turns green and red when you press power button? If yes, then check display panel voltage. Some displays works on 5V, some on 3.3V and some on 12V. Good source of info ishttp://www.panelook.com/.
LCD display datasheet doesn't contain a pinout!!!!!!!!!!!!! - Page 1
Forum section: electronics / beginners

author: Ferroto
author_rank: Frequent Contributor
timestamp: October 29, 2009, 05:51:55 pm
content: Datasheethttp://www.lumex.com/MstrCatalog/24_lcd_information.pdfDigikeyhttp://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en&site=CA&WT.z_homepage_link=hp_go_button&KeyWords=67-1781-nd&x=0&y=0The data sheet does contain a diagram showing rw pins and d0-d7 etc... but they aren't numbered so i just received the LCD display and have no idea how to interface it because it has a 16pin header with no descriptions. Is there a standard pinout for LCD displays that I'm not getting?Btw I've already ordered the LCD display and it has just arrived

author: Ferroto
author_rank: Frequent Contributor
timestamp: October 29, 2009, 05:59:52 pm
content: Guys never mind i just found the pinout in another piece of documentation on the digikey page
LCD Display Vs LED Display Common Pins  - Page 1
Forum section: electronics / beginners

author: 2X
author_rank: Frequent Contributor
timestamp: March 10, 2025, 06:43:52 am
content: Hello,I am working with the “LCD-S401C52TR” and I measured 3Kohm between the two common pins.When I only connect one common pin (instead of two) the LCD display all the digits fine and if I connect the two common pins together in the ground doesn’t change nothing at all in contrast, viewing angle etc. Οn the other hand on a 7 segment display there two common pins (it works also fine when one common pin is connected) maybe for current consumption?... but in LCDs the current is imperceptible.Why there two common pins instead of one and why the resistance between the two common pins is not zero like on LED 7 segment displays?LCD-S401C52TR pinout:https://www.farnell.com/cad/1942920.pdf

author: jwet
author_rank: Frequent Contributor
timestamp: March 10, 2025, 04:21:36 pm
content: The two technologies are just really different.LCD's use transparent, conductor tracks on glass (Indium/Tin?) to carry current. This stuff isn't a great conductor. An LCD segment is a capacitor, it draws no DC current and a miniscule AC current. Being fed by a few k-ohm source is no problem at low frequencies common in LCD drive schemes. The few K you measure between the commons could cause some segments with have longer common runs to show differences in contrast at higher frequencies or low/high temperatures. At low temps, the fluids slow down and at high temps, their DC leakage increases. Using both commons make problems of varying contrast lower over the display.LED's have lead frames with very low resistance- they draw real current (10 mA/segment +), this adds up and in large multi digit apps, board resistance can get in the way and cause issues. These extra commons are useful for easing layout and keeping supply impedance minimized.The use of the extra commons is recommended but not strictly required in either case. Use them if you can.Both types have multiple commons and they're generally used to reduce impedance but the specifics are pretty different.Good luck,

author: 2X
author_rank: Frequent Contributor
timestamp: March 10, 2025, 08:57:40 pm
content: Quote from: jwet on March 10, 2025, 04:21:36 pmMany thanks for your detailed answer and for your time.

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: March 13, 2025, 05:57:00 pm
content: In an LED-based 7-segment display, the two common pins are typically directly connected inside the package.
LCD Display/Monitor humming or buzzing sound - Page 1
Forum section: electronics / beginners

author: sirNemanjapro
author_rank: Newbie
timestamp: January 30, 2014, 07:36:49 am
content: I came across multiple computer displays (computer monitors) that had strange noise emanating from the back of it.The noise is high pitched and often people might not hear it at all. It resembles a high pitch buzz, high pitch humming or high pitch sizzling.The problem, I believe, is because of the monitor power supply which is faulty somehow or became faulty over time and this is the culprit.Often it is fixed by raising the Brightness setting to 100%. However, one of my displays (I have three) is showing the same symptoms even when he is on stand by.Any idea on how to fix or what to do with this would be appreciated.

author: mariush
author_rank: Super Contributor
timestamp: January 30, 2014, 01:56:20 pm
content: Open it up, check capacitors to see if they're swollen or not, get an esr meter and check the capacitors even if they're not visually faulty..if that still doesn't fix it sound may come from inductors... get electric grade silicon and put some on inductors (coils of wire around a magnetic material - as electricity moves through the wire shrinks and expands around the material making sound)If that still doesn't fix it, the fluorescent lights (if the monitor uses fluorescent and not led) may be old and use more current than new lamps so the power supply now works harder to output that current - switching power supplies will change the frequency of operation and that new frequency may go into the audible range.
LCD Displays - Page 1
Forum section: electronics / beginners

author: Totalsolutions
author_rank: Contributor
timestamp: July 05, 2013, 02:25:15 pm
content: Hi,I'm hope I am not alone in asking this is and I have never seen explained before.Can anyone tell me how the connections around the LCD "glass" connects to the PCB ?That's the question.Reason for asking, I have 12 yr old car stereo and the LCD display fades and vanishes. It can come back in warmer / dryer weather in the UK! I have tried to "repair", re-aligning the conductive strips but to no avail. I have two other radio units now with the same "blank" display.I also managed to over spray (when cleaning a machine at work today) a display LCD. Some cleaner got into the display cover, and after stripping down and drying, got it going, but there were the little black conductive strips of material connecting the "glass" to the gold plated PCB lands. Do these needs replacing due to shrinkage or can they be reused, apply a little conductive paste ? ? ?How to check any connections are good, hampered, due to no access to the actual glass connections as they are invisible too ? ?What voltage do they use ? ?Thanks for the replies.Paul

author: ovnr
author_rank: Frequent Contributor
timestamp: July 05, 2013, 02:33:50 pm
content: Most LCDs are connected to the PCB using "zebra strips", which are elastomer strips that only conduct in the Z (up/down) direction.These may occassionally go bad, and need replacing. Getting replacement strips is... difficult at best, and I'd be very surprised if you actually found a working replacement. The strips themselves have varying thicknesses, pitches, and other properties, and are not generally interchangeable.You shouldnotuse any conductive grease on them - clean the display and PCB contact surfaces with a good cleaner (isopropyl alcohol, etc) which doesn't leave any residues, and reassemble.

author: sleemanj
author_rank: Super Contributor
timestamp: July 05, 2013, 02:36:01 pm
content: The rubbery strips are called zebra strips, if you look closely (you might have to look very closely depending on the density, or might be plainly obvious) you'll see that the black line on each side is actually alternating black and white (usually), black is conductor, and white insulator, so it conducts vertically, but not horizontally.Contacts on the glass press against one edge of the strip, the signals and power conduct through to the other side of the strip, and thus to the PCB.See also:http://www.fujipoly.com/usa/design-guidelines/89.html

author: amyk
author_rank: Super Contributor
timestamp: July 06, 2013, 10:36:35 am
content: Quote from: Totalsolutions on July 05, 2013, 02:25:15 pmUsually between 1 ~ 30 volts AC; exact values depend on the crystal material, segment size, etc.
lcd driver board - Page 1
Forum section: electronics / beginners

author: christos
author_rank: Regular Contributor
timestamp: July 23, 2014, 09:00:58 pm
content: hello..my lcd driver board from an 20'' widescreen display is dead..i found some on ebay but my resolution is 1680x1050here's the linkhttp://www.ebay.com/itm/LVDS-NTA93A-Universal-LCD-Display-Monitor-Driver-Board-For-20-Wide-Screen-/190753636734?pt=US_Laptop_Screens_LCD_Panels&hash=item2c69cd817ethis is a widescreen 20 inch driver board but the resolution is only 1600x900will it work?

author: mariush
author_rank: Super Contributor
timestamp: July 23, 2014, 09:45:00 pm
content: No need to create other thread, stick to the one you made before. And if nobody answered, probably the answer was no.Why do you ask us anyway, do you think someone magically knows? You'll have to see if the connectors (all besides the one with voltages and backlight on/off) match.The panel may accept the 1600x900 even if your panel was 1680x1050 but it's no guarantee.

author: christos
author_rank: Regular Contributor
timestamp: July 23, 2014, 09:46:00 pm
content: ok thx
LCD Driver Board - Page 1
Forum section: electronics / beginners

author: nicksydney
author_rank: Regular Contributor
timestamp: November 26, 2014, 11:32:47 am
content: Hi all,I'm reading about LCD and driver board and have a bit of understanding between parallel interface and LVDS. I came across this boardhttp://www.ebay.com/itm/HDMI-VGA-2AV-Driver-Board-Card-Audio-for-7-IPS-LCD-N070ICG-L21-Raspberry-PI-/171390339009?pt=LH_DefaultDomain_0&hash=item27e7a907c1which shows that it has parallel connector and also pinout for LVDS screen. On the page the ad mentioned "the Controller driver Board can be worked with 4.3-15.6inch LCD(Resolution: 1280*800)", my question is does this kind of board can support out of the box both parallel and LVDS ? and does this mean that I can pretty much buy any 800x600 (7 or 8inch) panel (with parallel connector) and hook it up to this board it will just work ?Thanks for the help

author: Rasz
author_rank: Super Contributor
timestamp: November 26, 2014, 12:28:05 pm
content: its preprogrammed forhttp://www.panelook.com/N070ICG-L21_Innolux_7.0_LCM_overview_17626.html

author: nicksydney
author_rank: Regular Contributor
timestamp: November 26, 2014, 10:24:35 pm
content: Thanks Rasz.So does this mean that most of the LCD driver board that are sold in the market are "programmed" specifically for a specific kind of panel ? or are there any generic kind of driver board that can accomodate both parallel and LVDS ?Thanks

author: nicksydney
author_rank: Regular Contributor
timestamp: November 27, 2014, 06:19:00 am
content: Looks like Adafruit has a product (https://www.adafruit.com/products/2219) that allows you to reprogrammed the chip (TTL to HDMI) for different screen resolution.Haven't found any for LVDS as yet.

author: Rasz
author_rank: Super Contributor
timestamp: November 27, 2014, 03:41:01 pm
content: its not about parallel/serial, lcds generally dont care about that one (you can convert on the fly using one chip)whats important is resolution and order of color/sync bits(standard usually switchable with grounding specific pins on lcd connector)there are universal controllers, for examplehttps://sites.google.com/site/lcd4hobby/5-lcd-as-pc-hdmi-av-tv-multidisplaythat adafruit chip has nothing to do with reprogramming, its is simply a DVI deserializer, it spits raw RGB from dvi/hdmi stream, it will work with most parallel LCDs IF you set correct timings at the source of the signal (there is no resolution scaling)
LCD driver ID - Page 1
Forum section: electronics / beginners

author: wcyb
author_rank: Newbie
timestamp: October 06, 2021, 10:37:08 pm
content: Hello everyone,I am having trouble finding information about an LCD display whose only labeling was "LY-CG1886". I found an identical one on this site (even the marking matches):https://detail.1688.com/offer/645521319631.htmlhowever, I can't find information about its driver or pinout description anywhere.Is there anyone here who can help me with this?

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 07, 2021, 09:23:38 pm
content: This:https://a.aliexpress.com/_vOxo1qThe driver if is ST7735S.The page took ages and several tries to load, uploaded the pics just in case.

author: wcyb
author_rank: Newbie
timestamp: October 12, 2021, 05:09:13 pm
content: That LCD from the link seems to be the one I was looking for!Thank you for your help.

author: mic8
author_rank: Newbie
timestamp: March 27, 2025, 06:02:27 pm
content: Hi,normaly i don´t like postings on such an old thread but i am looking for exactly the display above.It is used in an REINERSCT device called tanJack photo and the display is broken by accident.Does anyone know where i can buy the mentioned display?I tried already google picturesearch and wayback machine but i can not restore the information of the posts above (Links are not working anymore).Also checking countless items on Aliexpress did not lead to success.Thanks in advanceMichael

author: DavidAlfa
author_rank: Super Contributor
timestamp: March 27, 2025, 10:10:37 pm
content: Use Aliexpress own image search, this was the first result:https://www.aliexpress.com/item/1005008335183641.html

author: mic8
author_rank: Newbie
timestamp: March 28, 2025, 05:46:50 pm
content: Thank you very much - I did not know that aliexpress has an imagesearch engine...
LCD issue only on cold start - Page 1
Forum section: electronics / beginners

author: hap2001
author_rank: Regular Contributor
timestamp: November 01, 2024, 12:34:38 pm
content: I have an used IPS panel that have red tint on border when cold start, and goes away in less than 10 minutes.I cannot have a good shot by camera, so I made an exaggerated demo picture as attached.Seeing in person, it's mostly noticeable on white background.What could cause this?

author: u666sa
author_rank: Frequent Contributor
timestamp: November 01, 2024, 06:28:13 pm
content: Panel finished.

author: Postal2
author_rank: Frequent Contributor
timestamp: November 01, 2024, 06:37:01 pm
content: Quote from: hap2001 on November 01, 2024, 12:34:38 pmLow VGL, presumably IPS is installed instead of TFT.

author: hap2001
author_rank: Regular Contributor
timestamp: November 02, 2024, 12:58:27 pm
content: Quote from: u666sa on November 01, 2024, 06:28:13 pmYours look like backlight bleeding, which is different from mine.

author: hap2001
author_rank: Regular Contributor
timestamp: November 02, 2024, 01:00:46 pm
content: Quote from: Postal2 on November 01, 2024, 06:37:01 pmIt's a laptop panel with integrated driver, sorry I didn't make it clear.It's more likely to be age related. I'm just want to know the exact cause.

author: Postal2
author_rank: Frequent Contributor
timestamp: November 02, 2024, 06:03:34 pm
content: Quote from: hap2001 on November 02, 2024, 01:00:46 pmI say again (second time) - check the voltages. Find your panel and check the correct voltages yourself. The Vcom line consumes a lot of current, check it first. (display in the photo is brand new IPS with incorrect voltages)And yes, after 10 minutes the edges become lighter, with the correct voltage the edges become light immediately.
LCD Lenses - Page 1
Forum section: electronics / beginners

author: Annakin4
author_rank: Contributor
timestamp: February 15, 2016, 01:24:05 pm
content: Hey all,So I want to make some ski goggles that hopefully displays direction, speed, coordinates, and which way is down (When foggy sometimes you can't tell which way is down) and I was thinking of taking a Nokia 5110 LCD and taking out the back light, and the back panel so you have just the bare Liquid crystal layer and use the sun as the back light and mount to the lens of my goggles. Would I be able to do this without damaging the LCD or do you have a better idea?I know this isn't a very practical option for a screen since it's so low res and it'll be close to my eye but I want to mess around with itThanks O0

author: Cliff Matthews
author_rank: Unknown
timestamp: February 16, 2016, 02:33:50 am
content: I for one, would not like anything crystalline in such close proximity to my eyes. I used to have some ski goggles (Uvex I think..) and at best, something transparent could conceivably fit down between the two lenses. However, opening that area is like opening a thermal pane window and condensation will appear once you're back on the slope, not to mention slow cold-LCD response and focusing on something so close.What about inventing an OLED HUD headband that is partly Velcro attached to the top of the goggles (to stop vibration shift) and shines its light down via optical pipe and forward to reflect back? (I think semi-transparent bronze tape is sometimes used...)

author: Annakin4
author_rank: Contributor
timestamp: February 16, 2016, 03:05:35 pm
content: Hm, will need to look into it. Thank you!
LCD Monitor PSU - Page 1
Forum section: electronics / beginners

author: giammyzanna
author_rank: Contributor
timestamp: February 17, 2018, 09:44:59 am
content: Hello, this is my first post here and I believe this is a very easy question.I have attached a schematic of an lcd monitor power supply. I have two different monitors but they have a VERY similiar primary side. Basically they won't power on, no standby, no nothing. The caps seem good at a glance.The first thing I did was to check the fuse and it's open (on both monitors) so I decided to replace it on the acer (I had only bigger fuses lying around, the one that was on the monitor was rated 4A) and as soon as I plugged it in the NTC on the other side popped (so the braker did) so I stopped there.First of all what is that NTC doing there, I know it's a temperature sensor so I can't see the use of it.Second, the dell monitor I think is pretty much the same so I decided to not do anything before anyone more skilled than me can help.Any ideas on what to check for?Thanks in advance!

author: Jwillis
author_rank: Super Contributor
timestamp: February 18, 2018, 03:45:40 am
content: First off those circuits are EMI filters and surge protection.Reducing noise into your system.There only part of the supply.If your blowing fuses then theirs a problem deeper in after the rectifier.That NTC is a negative temperature coefficient thermistor .It decreases resistance as the temperature increases.That is use as a surge suppressor.

author: 0xfede
author_rank: Regular Contributor
timestamp: February 19, 2018, 11:41:29 am
content: Hi giammyzamma, the NTC is there to limit the inrush current caused by fast charging of the big electrolytic CAP after the bridge rectifier.If your NTC blowed up you have probably a short circuit on the switching device. Other possible causes are the bridge, the rectifiers after the flyback transformer or the load itself.Best,0xfede
LCD portable dvd player screen hack? - Page 1
Forum section: electronics / beginners

author: sparkzap
author_rank: Contributor
timestamp: August 15, 2019, 12:44:42 pm
content: i have a few old portable dvd screens, but there is no inputthere are few videos youtube but lacking details.how hard would it be to make a VGA\hdmi input hack (not composite) or something universal for these screens?and yes i know i can get a used pc screen for $20 on ebay.has anyone tried this?https://www.ebay.com.au/itm/LCD-Controller-Board-MT561-B-Driver-LVDS-LCD-Screen-to-LCD-Monitor-DIY-Kit/172600011385

author: mariush
author_rank: Super Contributor
timestamp: August 15, 2019, 01:46:41 pm
content: best bet would be to open them up and figure out the panel verision and connection type then go from there.Your LCD panel is most likely 720x480 or 800x600... if you're lucky it may be 1024x768 .... you'll then need to find compatible lvds board.Also if those are old they may have cfl tubes instead of leds so you'd also need separate inverter or you'll need to hack the backlight.

author: sparkzap
author_rank: Contributor
timestamp: August 16, 2019, 01:48:06 pm
content: helloi have opened itits a lcd panelno cflwith the flat wiremaybe ill upload photos
LCD protocol reverse engineering  - Page 1
Forum section: electronics / beginners

author: SScattered
author_rank: Contributor
timestamp: September 20, 2025, 07:42:59 am
content: Hi,I have this displayhttps://hackaday.com/2023/09/11/cheap-lcd-uses-usb-serial/. The thing is I just want to replace the current microcontroller and increase the update rate of the display, possibly playing a video. Currently, I cannot play any video on it and even displaying an image on it takes around 2 seconds.What I did is, I hooked up my logic analyzer to the microcontroller pins and trying to figure out how the display works.Please check out the screenshots. I captured the data while filling the screen in red.I'm not sure if I named the pins correctly though.I appreciate any help. Thanks!I'm using PulseView. I attached the captured data also.

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: September 20, 2025, 10:59:03 am
content: Does the display use SPI communiation?

author: SScattered
author_rank: Contributor
timestamp: September 20, 2025, 11:04:03 am
content: Quote from: ahsrabrifat on September 20, 2025, 10:59:03 amI'm not sure yet. There's no any model or anything on the display. It has 40 pins, but I guess most of the pins are just duplicates or something cause the microcontroller has 17 usable pins.

author: SScattered
author_rank: Contributor
timestamp: September 21, 2025, 02:11:24 pm
content: bump

author: amyk
author_rank: Super Contributor
timestamp: September 21, 2025, 07:53:00 pm
content: Look up 40pin LCDs with the same resolution and see if the pinout matches.With that many pins it's likely to be a parallel interface, you just need to find the pinout and from there determine what the controller is. It will probably be something Philips-command-set compatible.
LCD Repair  - Page 1
Forum section: electronics / beginners

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 21, 2015, 10:05:32 am
content: what is the most common faults with LCD monitor power supplies?I have a Prolite E1908WS.When I turn it on it flashes the image makes a small noise then goes out again but the signal light stays on.I took it apartand powered the lamps with an inverter from a scanner and it worked, so it is not the lamps that is funny.the capacitors are also OK

author: wraper
author_rank: Unknown
timestamp: March 21, 2015, 10:26:59 am
content: CapacitorsareOK or just look not bulged? Second most common fault is CCFL transformer. Secondary winding(s) must measure about 1k resistance. If it is open, transformer is faulty.

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 21, 2015, 10:52:02 am
content: Quote from: wraper on March 21, 2015, 10:26:59 amcapacitors are not bulged not sure about resistance

author: GreyWoolfe
author_rank: Unknown
timestamp: March 21, 2015, 12:02:07 pm
content: Just because the capacitors don't look bulged doesn't mean they are good. The ESR can be very high. An LCR meter can tell you if the ESR is too high.
LCD replacement. What should I look for? - Page 1
Forum section: electronics / beginners

author: AN1527
author_rank: Newbie
timestamp: September 02, 2022, 08:33:36 am
content: I don't know if this is the right place for this so if you think there is a better place please let me know.I need some help finding a replacement LCD screen module.The original LCD screen that I was using is a SP-5-GFX1.Here is the specsheet:https://datasheet.octopart.com/SP-5-GFX1-Lascar-Electronics-datasheet-8864302.pdfIt was used as a way to monitor measurements on a PCB and was communicating with the onboard ATMEL IC.The LCD has given up and no longer works. I did have a quick look online and it appears the original SP-5-GFX1 is no longer available and is discontinued on every site I have found it on.So my ultimate question is: What do I need to consider when buying a replacement?I found quite a few LCD screens of the same resolution but they appear to use parallel interface and it looks like the orignal is using Serial.Is there a way to connect a parallel screen to a Serial interface?Also I have no access to the code that was written to communicate with the original screen so there's no chance of modifying the code. I don't know if this will cause a problem?Any suggestions and advice will be very welcome.Thank you

author: jpanhalt
author_rank: Super Contributor
timestamp: September 02, 2022, 09:54:21 am
content: If you can find one of the same size with the same controller (Sunplus SPLC 501C), you might be in luck. Otherwise any LCD of that size, voltage, and SPI(?) serial interface might be made to work, if you have the same pinout. That is, make an adapter board to get the right pinout.I say SPI, as the description is not clear; however, the pin descriptions (i.e., clock (SCL), chip select (!SS), and data (MOSI)) are consistent with 3-wire SPI. You would need to find the datasheet for that controller to confirm its protocol. Caution: While it might be 3-wire SPI, commands used by a different controller may be different and won't work.

author: AN1527
author_rank: Newbie
timestamp: September 02, 2022, 10:17:28 am
content: HiThanks for your reply.This was my feeling regarding the LCD. Is the driver more important as the firmware would have been written specifically for that driver?RegardsAiden

author: jpanhalt
author_rank: Super Contributor
timestamp: September 02, 2022, 10:44:28 am
content: Yes, the driver is important. If it were a character display, it might be Hitachi compatible and easily replaced.However, the 128 x 64 description is typical of a graphical display. For those, the instruction sets can be quite different.
LCD screen pinout - Page 1
Forum section: electronics / beginners

author: KILLSWITCH
author_rank: Contributor
timestamp: April 26, 2018, 03:16:06 am
content: I pulled this LCD from a PCB and can't find any info on pinouts for an LCD screen like this.Anyone have info or advice on how to test or power this LCD screen?Using the diode function on my meter I was able to light up some characters briefly by putting the + lead on one pin, - lead on another then quickly reversing the leads on those pins.Do LCD screens require some type of voltage pulse or sin wave?

author: KILLSWITCH
author_rank: Contributor
timestamp: April 26, 2018, 03:11:32 pm
content: Let me rephrase my question.I cant find any information on typical pinouts, voltages or current for LCD displays.Is there a typical current and voltage for LCD displays as a starting point to try?

author: mariush
author_rank: Super Contributor
timestamp: April 26, 2018, 03:27:34 pm
content: That's a "dumb" lcd display, just commons and segments.You need a LCD display controller or a microcontroller with a built in lcd display driver. These generate the voltages and everything required to properly turn on and off lcd segmentsSee alsohttp://ww1.microchip.com/downloads/en/AppNotes/00000658B.pdf

author: tron9000
author_rank: Frequent Contributor
timestamp: April 26, 2018, 04:18:35 pm
content: I had this problem ages ago, it looks like one I found, I made a video of how I tested it:https://youtu.be/7UOGlGn7JM8Muttley kindly helped me out by supplying this diagram (see attached)
LCD setup - Page 1
Forum section: electronics / beginners

author: Nickk2057
author_rank: Regular Contributor
timestamp: November 05, 2014, 04:18:57 pm
content: OK! so i am trying to get my LCD to work with my Arduino using a HEF4094 8-bit shift register chip. but i cannot find the code to use for it to use as a serial input for to use my Arduino for my program LCD smarty. Any idea's? the LCD is LCR2002ABTAR1-2Y and i have an Arduino UNO. and can the HEF4094 be used on the PC's Serial connection too? am just curious.Thanks.

author: HalfSpace
author_rank: Regular Contributor
timestamp: November 08, 2014, 09:28:12 pm
content: Hi Nickk2057,Is the LCD circuit using the 4094 like the circuit below?How are you connecting the LCD circuit to the Arduino UNO?HalfSpace

author: Nickk2057
author_rank: Regular Contributor
timestamp: November 09, 2014, 09:11:49 am
content: yes. but i cannot find the code to use the serial out connection through the Arduino board to the chip to the LCD.

author: HalfSpace
author_rank: Regular Contributor
timestamp: November 09, 2014, 09:12:59 pm
content: Hi Nickk2057,Try the link below it has some code for this LCD setup and some links.http://playground.arduino.cc/Code/LCD3wiresHalfSpace

author: Nickk2057
author_rank: Regular Contributor
timestamp: November 10, 2014, 03:11:26 pm
content: Thank you @HalfSpace but with that i see no way to have it as serial out to the LCD. how do i do that?

author: HalfSpace
author_rank: Regular Contributor
timestamp: November 10, 2014, 11:11:13 pm
content: Hi Nickk2057,If you want to drive a parallel interface LCD through an arduino from LCD smartie, try the link below. It doesn’t use the HFE4094 chip but more arduino ports.http://waihung.net/lcd-smartie-through-arduino/HalfSpace
LCD Smartie + Arduino Nano + 10937P-50 Alphanumeric VFD Help??? - Page 1
Forum section: electronics / beginners

author: hydrolisk1792
author_rank: Contributor
timestamp: November 22, 2017, 11:25:30 am
content: Hello EEVBlog community. I'm new here and new to the forum. I apologize ahead of time for stupid questions here. Okay I have a Alphanumeric starburst type display from a Rowe Jukebox. It is a 1x16, and has 16 segments per character. I know the pinout of the display already and am able to power it up as well. At the moment I have the Samsung_16LF01_VFD library running on an Arduino Nano and all I get is a jumbled mess and can't seem to figure out how to program this. It is supposed to just be a Hello World script that is running on it but it is just rubbish on the screen. I'd like it if someone could come up with an Arduino library that can run this display through the arduino as a serial display I can then setup through LCD Smartie. I have the datasheet for the on-board chip the display uses, that is what I used to pinout the connector on the display. The chip is the 10937P-50 / 10937P-40 chipset. I have attached the datasheet as well. Any help would be massively appreciated. I'm still pretty new to this side of programming and Arduino. Also I have the Nano if that helps. Also the only pins on my display are SDA, SCLK, POR, Positive 8VDC, and GND. If you would like anymore information on this display, please let me know. I've already Googled out this thing and can't seem to find anything useful on it. I have already posted this to the Arduino forums but no one seems to be responding to me on it. I am willing to work with someone on this because it will also be a learning experance for me in the long run and I can maybe use this knowledge later on with something similar.P.S. It would be appreciated if the LCD Smartie display driver was a pre-existing one like crystal.dll or matrix.dll or something similar. Also these are commonly used in Fruit machines and Jukeboxes. I got mine out of a Rowe CD Jukebox from my workThanks a bunch!

author: danadak
author_rank: Super Contributor
timestamp: November 22, 2017, 12:10:03 pm
content: Work on this a bit at a time. Start by generating a control word and spiting it outon a pin, use the test mode as a starting point. This is simple in code, define avariable to contain control word, then a loop that sets/resets a pin on a bit basisof the variable followed by a toggle of a pin to clock bit value into V/F. See if youcan get display into test mode.Then move on to other commands.Regards, Dana.

author: hydrolisk1792
author_rank: Contributor
timestamp: November 26, 2017, 09:32:51 am
content: I have found a library that lights the thing up but it is just all a jumbled mess. I have a thread on the arduino forums for help because I know little to nothing about this aspect of programing with the Arduino, but on there it just seems like I'm getting the run around... Here is the link to the thread so you can see how far we got (not much of anything lol) Three pages of posts and not much has been done.http://forum.arduino.cc/index.php?topic=513312.0
lcds - Page 1
Forum section: electronics / beginners

author: abdullahseba
author_rank: Frequent Contributor
timestamp: July 29, 2014, 09:48:31 am
content: is there a manufacture that can make big custom colour lcds with curves

author: amyk
author_rank: Super Contributor
timestamp: July 29, 2014, 11:30:24 am
content: Yes but it'll cost you quite a bit and the minimum order quantity will be enormous.
LCR circuit viewed on a VNA - Page 1
Forum section: electronics / beginners

author: GonzoTheGreat
author_rank: Regular Contributor
timestamp: January 30, 2019, 11:01:55 am
content: I got to use a 2-port Vector Network Analyzer in my school for the first time.I can make S11, S22, S12 and S21 magnitude measurements as well as Impedance and Admittance on S11, S22, S12 and S21 at different frequencies.I calibrated the VNA and connected an air cored coil to Port1 and tried some S11 measurements.I am puzzled at the myriad of peaks and dips that I am seeing.1) Which one of them is the LC resonance ?2) At what frequency the most MMF is generated inside the coil ( magnetomotive force, ampturns) ? ( someone told me that if the RF current flows in the inter-turn self-capacitance (or in any other parallel capacitance) then it does not flow in the coil's windings and does NOT contribute to the MMF inside the coil )I am well aware that only ideal coils are composed solely of inductance and that real world coils also have self-capacitance. This capacitance forms a small LC circuit and that combined with the resistance of the wire forms an LCR circuit.The diagram below shows that the reactance of the inductance increases with frequency and the reactance of the capacitance decreases with frequency.3) Does that mean that as the frequency increases, less and less current flows in the inductance and more and more current flows in a capacitance ?
LCR meter and BLDC motor - Page 1
Forum section: electronics / beginners

author: ammjy
author_rank: Regular Contributor
timestamp: December 03, 2019, 03:45:19 pm
content: Hello, EEVBlog Users !Always Thanks you for your time.If you don't mind, I would like to ask about measuring internal RLC components of BLDC motor with LCR meter.(My LCR meter is DE-5000)first, Please see the attached figure of BLDC motor.If want measure Resistance and Inductance of one phase in A,B,C phases.after measure between A-B and B-C or C-A, simply divide with 2 is will be okay ?BLDC motor has magnet and coils inside. and these things can be rotate.so, I am so confused that how I can measure reliably internal resistance and inductance with consider magnet, coil, rotationPlease, let me know,,Thanks you for reading, I appreciate.
LCR Meter HP 4262A and lithium batteries inside - Page 1
Forum section: electronics / beginners

author: walter.brollo
author_rank: Newbie
timestamp: February 21, 2023, 02:00:50 pm
content: Hi, can someone tell me if the LCR Meter HP 4262A has lithium batteries inside to power memories with factory data? Thank you

author: jonpaul
author_rank: Super Contributor
timestamp: February 21, 2023, 02:53:26 pm
content: nosee service manual
LCR Meter U1733C Auto Identification Series-Parallel Mode - Page 1
Forum section: electronics / beginners

author: 2X
author_rank: Frequent Contributor
timestamp: November 10, 2024, 09:11:53 pm
content: Hello,I would like to ask what means the Down and Up column for each frequency and range. For example, at 20 H range, it writes that uses Parallel Mode for Down and Serial Mode for Up in order to measure an inductor. What means by Up and Down. I can't understand what mode uses in order to measure an inductor at 20H range @100Hz .According to the below article (generally speaking) “series equivalent circuit mode is used when measuring low-impedance elements (with an impedance of approximately 100 Ω or less) such as high-capacity capacitors and low inductances” and “parallel equivalent circuit mode is used when measuring high-impedance elements (with an impedance of approximately 10 kΩ or greater) such as low-capacitance capacitors and high-inductances”.https://www.hioki.com/global/learning/usage/lcr-meters_2.html

author: TimFox
author_rank: Super Contributor
timestamp: November 10, 2024, 10:06:00 pm
content: It should be mentioned somewhere in the manual.My guess (not having the manual) is that "down" and "up" refer to the aftermath of an auto-range switching near the boundary between decade ranges of inductance.
LCR meters and ESR - Page 1
Forum section: electronics / beginners

author: Floyo
author_rank: Regular Contributor
timestamp: January 06, 2011, 07:21:15 pm
content: Some time ago I bought the Agilent U1731B LCR meter. And of course I would like to be able to measure ESR. I thought that measuring the resistance of a capacitor in series mode measurement would yield the ESR of the cap. After reading a post in the BK precision LCR meter review topic I wasn't to sure that my theory added up. So what do you do when you don't know weather something is correct or not, you experiment.http://wiki.xtronics.com/index.php/Capacitors_and_ESROn this page I found a formula that would let me calculate the ESR with the Q and impedance of a cap. So what I did is measure the Q of the cap, the value and the resistance in series resistance measurement mode.Here follow the resultsCode:QCFZcESR Measured series resistance14,49,44E-0041201,4050,0980,0964,763,77E-0031200,3520,0740,0657,44,04E-0031200,3280,0440,043136,15E-0041202,1570,1660,166114,13E-0041203,2140,2920,30214,88,60E-00512015,4181,0421,0089,49,14E-00512014,5141,5441,50516,84,47E-00512029,6781,7671,74631,74,52E-00512029,3170,9250,90978,89,70E-00810001640,77320,82218,031721,04E-00710001536,2458,9329,82359,97E-00510001,5960,0072,146So as you can see, most of the measurements and calculations match up pretty well, until I get to the Film-caps of 100nF where the calculated ESR is extremely low (high Q) but the measured resistance is quite a lot higher.So my questions are, Does the measuring of the resistance of a cap in series mode on an LCR meter give you the ESR?And, of course, Why does the calculated ESR differ so much from the measured resistance once I measure 100nF foil type caps (I measured a few more then are displayed in the table, and they all give about the same result)?Thanks in advance.

author: tyblu
author_rank: Frequent Contributor
timestamp: January 07, 2011, 09:55:27 am
content: What is the accuracy and precision of that meter for Ohms in that range?

author: Floyo
author_rank: Regular Contributor
timestamp: January 07, 2011, 02:10:02 pm
content: In the 20 Ohms range, the specs are as follows, 1.2%+40 counts at both 120 and 1Khz. This is in parallel mode, series mode is not included in the specifications.So even in a worst case scenario the 2 Ohm's on the last cap is way out, 1.2% of 0,007 is 0,000084. The maximum value that the meter can display is 19,999 Ohms, so it should read a maximum of 0,047 Ohms. In practice the value is about 50 times higher. I don't expect it to read these very low values accurately, but I do think it is quite strange because it measures 1 Ohm 1% resistors just fine.

author: tyblu
author_rank: Frequent Contributor
timestamp: January 07, 2011, 02:20:18 pm
content: I don't think the values would be the same. Series resistance (ohmmeter) would expect a frequency independent load, and may use a very low or DC voltage to probe it, while ESR assumes a cap or inductor, and will seek the proper frequency (~kHz for caps, ~DC for inductors). I am not sure, though, as your meter is made by people much quicker than I.
LCR meters, how do the polar caps withstand the AC test frequency? - Page 1
Forum section: electronics / beginners

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: June 26, 2023, 02:46:53 am
content: Electrolytic and tantalum capacitors have a polarity for a reason. So when we test them with an LCR meter, how do they withstand the AC test frequency? Even if it's not fatal to the capacitor, doesn't it degrade them?Do you have to add a bias voltage or something?Thanks!

author: TimFox
author_rank: Super Contributor
timestamp: June 26, 2023, 02:55:47 am
content: The DE-5000 applies approximately 600 mV rms to the DUT, which shouldn't destroy it.It would be better to apply a DC bias voltage to a polarized capacitor to get a better measurement of its capacitance and ESR.

author: mawyatt
author_rank: Super Contributor
timestamp: June 26, 2023, 03:45:54 am
content: Our experience over the years has been as long as the reverse voltage is small, dynamic, and not static reversed DC bias levels, no serious degradation was observed, and Tantalums behaved better than typical Al electrolytics under reversed conditions.Some of the better LCR meters allow the user to set the stimulus amplitude and source impedance, as well as the DC Bias voltage. All these are useful with various DUT devices, when attempting to achieve meaningful DUT measurements with polarity sensitive and non-linear DUTs.We created and posted a DC Bias fixture for bench type LCR meters to allow utilizing an external DC bias source with meters that don't offer direct DC Bias capability. This fixture won't work properly with LCR meters that don't have a separate DC Short Calibration procedure, which must be bypassed since the LCR meter with the DC Bias fixture is now AC coupled, thus won't pass the DC Short Cal proceedure. Because of this limitation, handhelds like the DE-5000, won't work with the fixture.Best,Best,