hybridfree/eevblog-posts huggingface dataset:
lcd 8*4in - Page 1
Forum section: electronics / projects

author: jaRON
author_rank: Contributor
timestamp: September 29, 2011, 06:11:41 am
content: I looking for a lcd 8*4in. for a project

author: Bored@Work
author_rank: Super Contributor
timestamp: September 29, 2011, 06:13:51 am
content: Quote from: jaRON on September 29, 2011, 06:11:41 amThanks for informing us about your current activity.

author: IanB
author_rank: Super Contributor
timestamp: September 29, 2011, 06:30:47 am
content: jaRON, your posts are beginning to be highly entertainingHere's a hint: if you are unable to construct full sentences and paragraphs with a logical and reasoned outline of your plans, you are highly unlikely to be able to construct a real working electronic project.

author: metalphreak
author_rank: Frequent Contributor
timestamp: September 29, 2011, 03:11:42 pm
content: I just ate a tiny spider that was sitting on the rim of my cup
LCD advice - Page 1
Forum section: electronics / projects

author: ScottyAU
author_rank: Contributor
timestamp: July 07, 2014, 11:31:25 am
content: Hi all,I've after an LCD I can use in 2 particular ways:Rasberry PiOld game consoles/computers (Commodore64, Apple //c etc)I've only just started looking - and these are the three i am considering at the moment:http://www.ebay.com.au/itm/New-7-Inch-TFT-LCD-Display-Monitor-for-Raspberry-Pi-Driver-Board-HDMI-VGA-2AV-/231183246381http://www.ebay.com.au/itm/2channel-Video-Input-9-Inch-TFT-LCD-Widescreen-Headrest-Car-Rear-View-Monitor-/321369549000http://www.ebay.com.au/itm/NEW-Arcade-game-RGBCGAEGAYUV-to-VGA-HD-Video-Converter-Board-GBS8200-/3710504522701st one has the advantage of HDMI/vga inputs, but its not in a case.2nd one is in a nice case good to go, but its not as good in terms of input options.3rd one would just be used with an existing monitorWondering if anyone has any thoughts/experience/tips?Thanks,Scotty
LCD alternative to 0.96" OLED display - Page 1
Forum section: electronics / projects

author: hcglitte
author_rank: Regular Contributor
timestamp: January 11, 2017, 12:26:11 pm
content: Hi,I am looking for a replacement graphic LCD display for our current OLED 0.96" 128x64.(Current OLED:http://www.buydisplay.com/default/monochrome-0-96-128x64-oled-display-module-ssd1306-blue-and-yellow)The reason is that an LCD is read more easily in direct sunlight.Our current application has a space constraint of 3.3 mm for the thickness of the module.So, we are looking for a thin graphic LCD (COG) with LED backlight.We have only come over displays that are a bit thicker due to the backlight LED.If anyone knows of any source, help is appreciated.HC

author: cezar
author_rank: Contributor
timestamp: January 11, 2017, 02:24:54 pm
content: perhaps the nokia ones?http://www.ebay.com/itm/400488314619
LCD Backlight power supply using LED - as feedback? - Page 1
Forum section: electronics / projects

author: MatCat
author_rank: Frequent Contributor
timestamp: January 06, 2014, 05:36:48 am
content: I am working on setting up a PCB to drive an LCD, and I noticed in this schematic I am looking at the switching regulator which drives the backlight has its feedback coming from the backlight LED cathode line, with some low resistance to ground (I am assuming to set MAX current), I haven't seen this setup and I am going to assume it keeps the current constant? And if so what is controlling it? I am assuming the resistor to ground, the closer 0 you get the closer to the max output of the regulator you get?

author: amyk
author_rank: Super Contributor
timestamp: January 06, 2014, 08:13:16 am
content: R2 is the current sense resistor. The higher the current the higher the voltage across it, and thus the higher the voltage on the FB pin.Read theTPS61041 datasheetfor more details.

author: daveatol
author_rank: Regular Contributor
timestamp: January 06, 2014, 12:30:26 pm
content: As mentioned, R2 is the current sense resistor. When regulating, the voltage across this resistor is 1.233V (the FB reference voltage); thus the LED current for the circuit shown is 1.233V / 24R = ~36mA

author: MatCat
author_rank: Frequent Contributor
timestamp: January 06, 2014, 05:59:50 pm
content: The datasheet really doesn't explain it at all, plus 1.233/24 = 0.051. Perhaps I should better ask, exactly how does the feedback work? In this case we are driving 7 backlight LED's in series, this switching reg can put out up to 28 volts, though a zener is there to cut the max output voltage (the listed one is 16v but I am going to do this circuit with a 22.4v), now in a normal setup you would have the feedback coming in from the output with a resistor divider to set the output, but in this case the divider is based on the return path of the LED's, which in this case the total forward voltage drop of all of the LED's is 22.4v, so the voltage coming out should be 0, so does that mean this switching reg is designed to keep the LED's at exactly their max current draw being limited only by the current sense resistor?

author: dannyf
author_rank: Super Contributor
timestamp: January 06, 2014, 06:23:21 pm
content: All regulators work by changing their output so that the voltage on the feedback pin is as desired. In this case, the regulator will output the necessary voltage over the leds so that 1.23v is dropped over a 24ohm resistor ie. Constant current of 36ma, regardless of leds used - within reason.

author: MatCat
author_rank: Frequent Contributor
timestamp: January 06, 2014, 06:37:09 pm
content: Ok I see it now, so you effectively get the circuit regulating (in this case) to 36ma at 22.4v, which will drive a total of 252ma into the LED's (252ma at 3.2v that is), since there are 7 LED's they all have a voltage drop of 3.2v, all of them will use up 36ma each. Which makes sense since the rated power of the backlight LEDsis exactly 250ma.
LCD becoming dark after few month - Page 1
Forum section: electronics / projects

author: Lunasix
author_rank: Regular Contributor
timestamp: March 06, 2019, 10:19:14 pm
content: Hi,we have a problem with Storm (brand) displays which become dark after few month of outdoor use. It is the "extreme condition" model, given to work up to 70°C. We have hundreds of this display, mounted in big stainless steel boxes. The internal power dissipation is very low, if we consider the size of the box. We do not know the real temperature in summer, but it is mostly self heating due to the sun, and we think it is not above 70°C. We must wait next summer to have precise values. The display is angled at 45°, so the sun can touch the display at right angle. This position was authorized by the manufacturer. And we have lot of theses displays which fail with a dark spot on it. The manufacturer tell us we are the only one to have this problem, and for instance do nothing practical. The shape of the spot let us think that solar ray is mostly responsible, corners of the display are less concerned, due to shadow. Displays facing north seems to survive longer time, but it is not easy to have precise datas as they are throughout the country.What could be the most probable origin of this problem ? UV-A, UV-B, UV-C, self-heating due to the sun (infrared), temperature, all of these...? Can a UV-A film filter (used for shop windows) minimize the problem ?I'm fed up of this manufacturer, so, if I want to build my own display (now, I'm able and can find time and money to do that), what lcd should I use, what protection should I add ?

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 07, 2019, 12:52:04 am
content: IMO, if the symptom is that the LCD darkens, it's usually due to overheating. Problem is, even though the average internal temperature of the enclosure may never exceed 70°C, the liquid crystals themselves which absorb infrared when in the "on" (black) state can get extremely hot under direct sunlight and become permanently isotropic.UV is also a problem but I think it will tend to make the display progressively "washed-out" rather than dark.I think you should use both IR- and UV-blocking filters in front of the displays. Don't know about Storm displays but they don't seem to have efficient filtering.You can take a look there for instance:https://dontech.com/dontech-heat-shield-transparent-ir-blocking-filters/
LCD bias in 1/4 1:8MUX displays, why so many levels? - Page 1
Forum section: electronics / projects

author: flimshaw
author_rank: Contributor
timestamp: October 31, 2018, 04:08:58 pm
content: I'm trying to understand how multi-level LCD biasing works, and I have run into something I can't wrap my head around. I'm studying waveform charts for "frame inversion mode" driving for a 1:8, 1/4 bias LCD, which is commonly said to require 5 voltage levels. The COMMON pins are pulled to either VCC, 3/4 vcc, 1/4 vcc, or GND. The SEGMENT pins are either VCC, GND, or 1/2 VCC.My question is: if the point is to limit the voltage difference between the segments and backplanes that are not being driven, why not set both the backplane and the segment to 1/2 VCC? Why are we keeping a 1/4 VCC voltage difference between them? I've attached a waveform diagram from a Rohm lcd driver that illustrates it. I feel like I must be missing something.Thanks!
LCD blanking interference from spark gap - Page 1
Forum section: electronics / projects

author: LukeW
author_rank: Frequent Contributor
timestamp: August 31, 2016, 08:30:40 am
content: I have a generic HD44780 LCD display module driven by an AVR.The AVR drives an automotive ignition coil, where the switching silicon is inside the coil assembly and the coil is supplied with 12V and ground and a logic-level trigger signal from the ECU (AVR in this case). The firing signal is about 40Hz with 1mS on-time.+12V enters the electronics box, is fused, regulated with an LM2940 for the 5V logic supply and the 12V rail goes through a current shunt and out to the coil / spark gap, which is about 50cm from the grounded metal box with the LCD.So that all works just fine, but occasionally the LCD will go completely blank and stay blank (even though the microcontroller keeps running and the spark is running fine) and the LCD won't recover without a power cycle.Is this likely to be a conducted or radiated EMI effect, and what's the best way to stop it?

author: Buriedcode
author_rank: Super Contributor
timestamp: August 31, 2016, 01:11:28 pm
content: Hard to say without a scope capture of the power lines. The LM2940 is pretty good for 'nasty' power supply environments like automotive, or instances where the main power supply is switched across inductive loads, but its capabilities are there really just to stop it dying, and to protect devices on the output - not to somehow continue to supply power when its input drops. You're shorting your power supply across something with a massive inductance, so the 12V is bound to be bouncing all over the shop.It could could easily be radiated EMI because as you know sparks.... so things to try:- Heavier capacitance on the regulators output, possibly adding protection diodes to the reg.- Check the 5v line with a scope for any major dips - the LCD could just reset from brown out.- Check the IO's to the LCD: perhaps ringing on its lines, along with multiple 'E strobe' glitches could clear the screen, unlikely though. serial resistors and/or ferrite beats on the IO's with 47pf caps might help.- Put the LCD module in a Faraday cage;I'm afraid I'm not overly experienced in dealing with this sort of thing, but as stated above there are many things to try to narrow it down. Whilst it could easily be radiated, I suspect its more conducted, got a schematic of the whole setup?

author: StillTrying
author_rank: Super Contributor
timestamp: August 31, 2016, 07:21:57 pm
content: Quote from: LukeW on August 31, 2016, 08:30:40 amI would think that the Enable line of the LCD is the thing to look at.As a bodge, a digital output could provide the LCD's 5V, so that the uP could power cycle and re-initialize the LCD when it thinks it's stopped working.
LCD Contrast voltage... - Page 1
Forum section: electronics / projects

author: alank2
author_rank: Super Contributor
timestamp: February 14, 2020, 09:39:00 pm
content: I tried out a new display LCD display that is 3.3V and the data sheet says around 0.1V is a good voltage for the contrast pin.https://www.newhavendisplay.com/nhdc0220aafswftw-p-3886.htmlThe datasheet shows the contrast being subtracted from VCC which I find odd.My typical method to test contrast on an LCD is to blink a cursor. You will usually find that if the contrast isn't ideal that it is visible this way. For example, it might take too long to transition from unlit to lit, or too long from lit to unlit depending on the contrast voltage.I hooked up the contrast pin to my AWG and played around with it and ideal seems to be around -100mV. 0V is fine. 100mV is starting to show a cursor that seems more off than on, 200mV is worse, and 300mV shows dimming in other character's pixels that are not changing. -200mV is shows a cursor that seems more on than off, -300mV shows unlit pixels starting to darken.So this is a range of -300mV to +300mV for what I would call a valid adjustment. Ideally one would have a pot that had this range to switch between, or perhaps I could generate it with a PWM and RC network like I did on another project.Is there an easy way to make -0.3V and 3V from a 3.3V vcc? I'm wondering if it is worth the effort. Maybe just grounding the contrast would be a suitable solution most of the time...

author: Vovk_Z
author_rank: Super Contributor
timestamp: February 15, 2020, 04:58:09 pm
content: Use potentiometer?

author: JXL
author_rank: Regular Contributor
timestamp: February 15, 2020, 07:36:34 pm
content: Most of my displays were OK at 0V, but some required < -1V. I used ICL7660 with a pot, so I can adjust from -Vdd to +Vdd.
LCD Display - AC Voltage? - Page 1
Forum section: electronics / projects

author: ulix
author_rank: Regular Contributor
timestamp: March 27, 2016, 07:15:26 pm
content: Hello,I was looking for an alternative for the HP QDSP-6064, which I found, now. Here:http://www.lumex.com/lcd-s401m16krOne Problem which I struggle is, the display is for 3V AC. What does that mean? Which is the Low Voltage and which is the maximum?There is some dev board from NXP which uses the display on a MCU, so it can't be for AC?!There are no resistors used, it's connected directly to the output pins. So these pins have 3.6V output voltagehttp://www.lumex.com/content/files/ProductAttachment/84201515841-LCD-S401M16KR.pdfI would be very happy if someone is able to help me... cheers

author: SeanB
author_rank: Super Contributor
timestamp: March 27, 2016, 07:53:42 pm
content: LCD displays need an AC drive on them, otherwise they will be damaged very quickly. The direct connection to the MCU requires the MCU to drive it with an AC signal, and arrange the drives for all the segments to either be in phase or antiphase with the one master backplane signal.Other LCD displays use multiple voltages to drive them, still AC but with levels such that only those segments that need to be on have the full AC voltage applied, the others that have to stay off having a lower AC voltage applied, as a LCD has a threshold voltage below which it does not turn on, and a small range where it varies in darkness. Those displays though typically have an integrated driver, using either serial data, parallel data or some form of I2C or LVDS drive into the controller which generates the drive patterns itself.
LCD display with photo frame - unusual 40-pin interface - Page 1
Forum section: electronics / projects

author: up8051
author_rank: Frequent Contributor
timestamp: September 23, 2022, 06:34:07 pm
content: Hello,I wanted to use a 6 inch 800x480 LCD display from a cheap photo frame.I expected that there will be a display with a typical RGB interface (40 or 50 pins), i.e. RGB signals (6 or 8 bits per color), HSYNC / VSYNC (synchronization pulses) CLK (clock) and DE (Data Enable) and signals related to the power supply and LCD backlight.Unfortunately, I had an unpleasant surprise, yes, the ribbon is 40-pin, but with a completely unusual set of signals.Some technical details:-foto frame based on the AMLOGIC AML6221 processor (unfortunately I have not found any documentation)- display 6 inches 800x480 40-pin ribbon- the display is labeled TL060W-V600-V2 (unfortunately there is no documentation here)However, I managed to find a diagram of a similar frame based on the same processor:https://usermanual.wiki/Document/texettf601tf602tf801tf802schematics.1012292288/viewTwo things can be seen in the diagram:- control signals for LCD are only RGB (6 bits each), DE and CLK are not HSYNC / VSYNC signals- unfortunately, a large number of required supply voltages: AVDD, VCC VSN, SSP, VGH, VGL (similar to displays with a 50 pin ribbon).And my question, has anyone met this type of LCD interface?Is the DE signal immediately a synchronization signal and then the data for the whole image is sent?RegardsJarekC

author: langwadt
author_rank: Super Contributor
timestamp: September 23, 2022, 06:56:38 pm
content: I believe it is sometimes called "DE mode" seems like all the timing is the same you just don't use the sync signals

author: up8051
author_rank: Frequent Contributor
timestamp: September 23, 2022, 07:08:56 pm
content: Thanks.I found a lot of information with the help of this phrase.

author: Kelindev
author_rank: Newbie
timestamp: August 19, 2025, 10:40:02 am
content: I pulled apart a cheap digital photo frame once and bumped into a similar 40-pin setup that didn’t match any standard I knew. Ended up tracing lines manually to figure out the signals. If you're just after a working photo frame without all the hassle,nixplay.comhas some that are plug-and-play and save you from digging through weird old interfaces.
lcd driver board - Page 1
Forum section: electronics / projects

author: jaRON
author_rank: Contributor
timestamp: September 29, 2011, 06:27:15 pm
content: I looking at the lcd LCT-H320240M35W for my fan controller. I like it to show the fan speed, Temperature and more. What I need to know were I can get or make a lcd driver board and the Pin I/o for the lcd.http://parts.digikey.com/1/parts/2004248-display-tft-lcd-320x240-lct-h320240m35w.html

author: johnmx
author_rank: Frequent Contributor
timestamp: September 29, 2011, 07:52:18 pm
content: That display is supported by Microchip graphics library:http://www.microchip.com/mal
LCD for a watch - Page 1
Forum section: electronics / projects

author: fax8
author_rank: Contributor
timestamp: January 19, 2012, 02:19:21 pm
content: Hello, I'm designing a watch like product and I'm looking for suggestions on LCD for such applications.The idea I have in mind was to use a general dot matrix LCD with backlight illumination, similar to themetawatch digital model. Of course, lowest energy consumption is better.I don't seem to find anything like that on Digikey, so I'm looking for you guys suggestions on specific parts or shops specialized in such kind of product.Thanks for your help,Fabio Varesano

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: January 19, 2012, 02:37:30 pm
content: Sharp Memory LCDs are awesome - very low power and high contrast. Mouser stock them.http://sharpmemorylcd.com/

author: fax8
author_rank: Contributor
timestamp: January 19, 2012, 06:46:06 pm
content: @mikeselectricstuff wow, great suggestion!Actually, a friend found that Metawatch, the kind of display I'm interested in (see link in my 1st post), is using MemoryLCD as confirmed bythis post.
LCD hacking idea - Page 1
Forum section: electronics / projects

author: Rachie5272
author_rank: Regular Contributor
timestamp: December 28, 2014, 11:42:37 pm
content: I have a bunch of bare LCD panels from old monitors laying around, and it would be nice to do something useful with them. Yes, I understand trying to interface them to display images and such is no small task, but what about something simpler? How about solid colours?Would it be possible to simply pull the colour data lines high or low, then pulse the clock line? If so, it would be very easy to control the colour with a microcontroller, making for some neat artistic creations.Any thoughts?

author: carcanhol
author_rank: Regular Contributor
timestamp: December 28, 2014, 11:52:07 pm
content: Maybe LVDS to HDMI or similar driver. im thinking in Flight sims or race sims.

author: amyk
author_rank: Super Contributor
timestamp: December 29, 2014, 02:17:58 am
content: You'll need to figure out what type of interface they use. Older ones with TTL are not that difficult to interface to, the LVDS ones will require a separate driver circuit.QuoteSomething like this?http://www.linusakesson.net/scene/craft/http://www.linusakesson.net/scene/bitbanger/

author: Rachie5272
author_rank: Regular Contributor
timestamp: December 29, 2014, 04:48:11 am
content: Interesting, but not what I'm thinking of at all. I mean not displaying anything but a single, solid colour over the entire LCD. More of a colour changing window than a display.It seems this would be as simple as permanently setting the colour data lines either high or low, and letting the controller read the colour data for every clock cycle. If I'm right, this means the electronics can be as simple as three DIP switches and an oscillator.
LCD HD44780 Charset query - Page 1
Forum section: electronics / projects

author: Wilksey
author_rank: Super Contributor
timestamp: August 06, 2021, 01:56:34 am
content: Hi,I have been using the HD44780 on 16 x 2 and 16 x 4 LCDs for a while now, and I just went to look up a character code for a symbol and found that the datasheet shows 2 x "table 4" character sets, noted by ROM Code A00 and ROM Code A02.But I can't see it mention this alternative code anywhere else, I wondered if it had to do with the 5x8 vs 5x10 char size so I changed the intialisation to select the alt char size but it made no difference.Does anyone know if this is an alternative built into some variant or if the 2nd charset is built into the HD natively, if so how does one go about selecting it as I can't seem to find anything useful in the instruction set.It is not that I necessarily need it but it does contain some chars that I have constructed myself but we are limited to 8 chars for the custom CGROM so it would be quite handy to have access to them.For information the datasheet can be found here:https://www.sparkfun.com/datasheets/LCD/HD44780.pdfCheersWilksey

author: amyk
author_rank: Super Contributor
timestamp: August 06, 2021, 02:07:13 am
content: Look at the second page of the datasheet. 'A00 is the "Japanese standard font", 'A02 is the "European standard font". They are separately orderable parts... or rather,were, since Hitachi itself hasn't produced these in over a decade. As such, it is highly unlikely you are actually using a genuine Hitachi HD44780 in your display. Note that the datasheet you linked is from 1999.

author: Wilksey
author_rank: Super Contributor
timestamp: August 06, 2021, 02:13:56 am
content: Hi amyk,Ah, that was an oversight on my part, seems as though I have a "Japanese standard font" variant, I know it is an old datasheet / controller, most are "Compatible" but the controller in my LCD is true to the datasheet.I guess as it is controller device part dependant I wouldn't be able to tell regardless as most are "blob" chips on these LCDs and all of the ones I have used seem to have the A00 charset.Ah well, it would have been nice but no worries.Thanks for the info!Cheers
LCD Microscope - Page 1
Forum section: electronics / projects

author: KD4CCF
author_rank: Contributor
timestamp: July 16, 2018, 06:09:18 pm
content: Saw these on FleaBay. Curious if anyone has used one and can comment on quality and usefulness.

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 06:23:13 pm
content: I have a model with a smaller display. It is good for inspection, but not for work. The display is laggy. I have not tried HDMI output, it may be better.
LCD picking help for project - Page 1
Forum section: electronics / projects

author: thinkpad4by3
author_rank: Newbie
timestamp: March 03, 2019, 08:01:53 pm
content: Hi guys,I'm looking to build a cheap scientific/graphing calculator as a project. I want to make it cheap as possible just as a challenge. The display doesn't need to be exactly these requirement, but the closer the better.96x64 or 128x64 resolution(or better)1.5" - 3.0"Technology doesn't matter, also kind of leaning towards Reflective STN because of price and power consumption.Preferably some kind of interface over driving raw.The cheapest I've seen is 10$ for a 1pc order, they didn't list any bulk prices. I'm pretty sure there are cheaper places, but I haven't been able to find anything. Is this the cheapest for a 128x64 STN Raw display, and if not, what places has it cheaper?

author: thinkpad4by3
author_rank: Newbie
timestamp: March 03, 2019, 08:24:17 pm
content: 1.4" display for $3.50 or 2.8" display for $6.50. Perfect, now I can see what the rest will cost. Probably will go with a 1.4" display given I want the total price of electronics under 10-15$.
LCD pinout - Page 1
Forum section: electronics / projects

author: electronics technician
author_rank: Regular Contributor
timestamp: March 12, 2021, 02:39:55 am
content: Ok so I have a 19cm (7.5in)LCD display and I would like to know if anyone could help figure out the pinout for it. It looks like a Made in China LCD. It has a driver board already so I think it just needs a input signal but idk which wire to put it any and all help is welcomed.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 12, 2021, 02:41:22 am
content: Picture of 1 connector

author: electronics technician
author_rank: Regular Contributor
timestamp: March 12, 2021, 02:42:51 am
content: Pic of 2nd and 3rd connector

author: amyk
author_rank: Super Contributor
timestamp: March 12, 2021, 02:28:57 pm
content: That looks like an analog LCD. What do you want to do with it exactly? The resolution isn't going to be very high, probably 480x234 or similar.Attached datasheet of main controller.
Lcd problem - Page 1
Forum section: electronics / projects

author: House91320
author_rank: Regular Contributor
timestamp: October 23, 2010, 10:25:26 pm
content: I bought an lcd display from a surplus store and I can't get it to work with my arduino . The data sheet number is - Densitron 2020a-ct. Pleas help.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 24, 2010, 01:53:06 am
content: pls provide link, picture, datasheet, code etc. someone might help
LCD question connection - Page 1
Forum section: electronics / projects

author: brian25
author_rank: Newbie
timestamp: February 27, 2014, 04:43:18 pm
content: hi sir & ma'am i want to use the LCD of my old phone nokia c1-01 in my project. is this possible and how the connection in the microcontroller?thanks

author: b2theory
author_rank: Contributor
timestamp: February 27, 2014, 04:58:45 pm
content: Its certainly possible. Does it use a FPC connector? Can you find out the part number?
Resistors before LCD FPC connector - Page 1
Forum section: electronics / projects

author: Koen
author_rank: Frequent Contributor
timestamp: November 26, 2016, 12:45:00 am
content: Hello,in multiple teardowns from both Dave and Mike, PCBs show resistors on LCD tracks before FPC connectors. Example :Seek Reveal Pro themal imager review & teardownat 18m20, components RN1 to RN5.What is their role and is there a commonly used value ?Thank you very much,Koen

author: langwadt
author_rank: Super Contributor
timestamp: November 26, 2016, 01:23:27 am
content: series termination, something like 25R
LCD Screen driver/controller board design  - Page 1
Forum section: electronics / projects

author: Epicycle
author_rank: Newbie
timestamp: July 23, 2018, 05:15:55 pm
content: Greetings EEVblog community,I have been working on a project that requires a small LCD screen. The following link shows the screen that best fits the design specifications of the screen.https://www.alibaba.com/product-detail/1-3-inch-lcd-module-for_60716398296.html?spm=a2700.7724857.normalList.1.54d4589094r0oD&s=pI haven't been able to find a premade driver/controller board for the screen and the datasheet for the ST7789H2 has not been very useful. Does anyone know how I would go about deriving the screen in the link above? I also do not need the touchscreen.Your time and expertise are appreciated.
LCD Screen for 3D printer - Page 1
Forum section: electronics / projects

author: adam440
author_rank: Newbie
timestamp: December 02, 2017, 12:05:53 pm
content: Hello,I'm working on stereolithography 3D printer that will use LCD panel. I won't go into details about how it works (google SLA LCD 3D printer). The important point is, that I need near UV-passing LCD. I'm talking about 460nm wavelength. I'll remove the backlight and install my own high power UV LEDs. Another requirement (although less important) is low viewing angle. The display should be as small as possible (ideally less than 10") and have resolution 1920x1080 or higher. In the worst case, the resolution could only be HD, but this directly affects the resolution of the printer, so the higher, the better. Price shall be lower than 400 USD.I'm a complete beginner when it comes to displays. I don't know if it's better to buy the panel and controller separately or together as a kit. I've found out, that LVDS interface is easiest to work with, as there are many controller boards and even more displays supporting it. But kits are dumb-proof and I don't want to debug one component for months. I've composed a short list of potential displays, but I have no idea about their UV-passing property. Do you know better screens and controllers? Could you help me to select the correct one? I appreciate any help.LIST:Kit 1:https://www.aliexpress.com/item/10-1-inch-2560X1600-2k-1440p-HD-screen-monitor-IPS-VVX10T025J00-DLP-projector-LCD-and-driver/32796452369.htmlKit 2:https://www.aliexpress.com/item/2560-1440-2K-5-5-inch-LCD-Screen-3D-VR-Headset-Glass-Virtual-Reality-HDMI/32794379549.htmlDisplay 1:http://www.panelook.com/LTL106HL01-001_Samsung_10.6_LCM_overview_20690.htmlDisplay 2:http://www.panelook.com/TX18D200VM0EAA_KOE_7.0_LCM_overview_19990.htmlLVDS Controller 1:http://www.lcdparts.net/MS531LC.aspxLVDS Controller 2:https://www.ebay.com/itm/HDMI-DVI-VGA-Driver-LVDS-Inverter-Kit-Convert-a-Bare-Laptop-LCD-into-Monitor/111115624120?hash=item19df01deb8:g:1~sAAOxyrUZRymfpPS: I apologize for any grammar mistakes. I'm not a native speaker.Cheers,Adam
LCD TFT (MIPI Serial) VDDIO ? Digital Power supply and Analog power supply - Page 1
Forum section: electronics / projects

author: carl0s
author_rank: Unknown
timestamp: May 12, 2018, 12:08:36 pm
content: I'm sorry for spamming the forums so much..Why does these LCD require 'VDDIO (digital power supply), as well as 'VDD analog power supply')?http://www.internetsomething.com/lcd/3.3-NMLCD-T334TOS-01.pdfSame for this one:http://www.mouser.com/catalog/specsheets/Visionox-8-10-2017-G1120TB103GF-001A.pdfIs it a reference for the differential serial data signalling?Lastly, the screen says typical 2.8v (but will work up to 3.6v, and break at 4v). Would you run this at 3.3v (this is already on my main board), or would you add a step down IC/regulator and run it at 2.8v?

author: carl0s
author_rank: Unknown
timestamp: May 12, 2018, 12:10:45 pm
content: Oh hang on.. is it if you want to use different voltage logic communications between the screen and e.g. MCU? hence digital voltage? and the analog voltage, well that's what the screen requires to perform its job ?

author: dmills
author_rank: Super Contributor
timestamp: May 12, 2018, 12:15:50 pm
content: VDD min is 2.5V (Electrical spec on page 7) which is kind of boring if your controller is a 1.8V part, VDDIO however is ok down to 1.65V so can be driven from a 1.8V supply and will then give IO levels compatible with modern 1.8V IO standards.3.3V is within the range given in the electrical specs table so if you are running with IO voltages that high then just connecting both supplies to that voltage will be fine.Regards, Dan.

author: carl0s
author_rank: Unknown
timestamp: May 12, 2018, 12:46:58 pm
content: Quote from: dmills on May 12, 2018, 12:15:50 pmThe board I am modifying/duplicating has 3.3v main supply to the display, and 'vdd' going to the VDDIO. There's no explanation what voltage this actually is though,... oh wait.. it's whatever the MCU is being supplied, and the MCU can operate on anything from 1.71v to 3.6v. So if I chose to run the MCU at 1.8v, this would come through to the VDDIO of the LCD, and it would work nicely. I think I get it now. Thanks
lcd touch fan controller - Page 1
Forum section: electronics / projects

author: jaRON
author_rank: Contributor
timestamp: April 01, 2011, 07:52:18 am
content: hi I'm new. I'm work on a new pc it is going to water cooling. It is go to have 16 fans on in. I looking to make lcd touch fan controller. I know to make a fan controller. I need help going from the data fan controller microcontroller to come up on the lcd. I like to make the go fast by touch the lcd.

author: dimlow
author_rank: Frequent Contributor
timestamp: April 01, 2011, 08:36:37 am
content: I understand your need, I once had many fans in my PC and could not find a controller that would manage them all. In the end I made my own 8 fan PWM controller. It could control each fan speed by set speed or they could be temperature controlled by one of the 8 temp sensors that could also be connected to the board. LCD displayed the fans speed and each temp sensor. Each fan speed sensor and temp sensor also had alarms if they failed or crossed limits. I was going to sell this but never thought there would be a need for it as I thought nobody would be as mad as me and have 8 fans in their PC. In the end I finished the controller and never used it as I upgraded my PCIm sure if you have managed the fan controller side of things then you could easily manage the LCD, my system was all done with one pic micro controller (18f4550). I was new to pics and electronics back then and now when I look back at what I had done I see there are many things I could have done differently. But it worked.Your request gives me new interest in my project, maybe one day I will make a new version of this and produce a few batches for sale.

author: Psi
author_rank: Super Contributor
timestamp: April 01, 2011, 10:38:13 am
content: It will be easier to use a lcd that has a controller built in. This way you can communicate with it at a slow speed using a normal microcontroller and just update pixels or draw objects when you want to.If you use a raw lcd panel then you need a powerful microcontroller to write all the pixel display data all the time, even when the lcd image isn't changing.Sparkfun sell a lcd with built in controller and touchscreen but it's probably a bit too complex for simple projectshttp://www.sparkfun.com/products/10089

author: DrGeoff
author_rank: Frequent Contributor
timestamp: April 01, 2011, 11:25:15 am
content: Why not build a wi-fi fan controller and use your iPhone as the interface to control the fans.

author: jaRON
author_rank: Contributor
timestamp: April 01, 2011, 07:54:24 pm
content: no iphone

author: jaRON
author_rank: Contributor
timestamp: April 01, 2011, 09:35:36 pm
content: If I use the Serial TFT LCD 3.2" with Touchscreen led and i have the fan controller what do i need now.
LCD with 16pins instead of 14pins? - Page 1
Forum section: electronics / projects

author: alank2
author_rank: Super Contributor
timestamp: April 29, 2015, 04:21:02 pm
content: I bought some 40x2 displays off ebay. One says HD44100FS on it and the other says uc-40207 on them. Both have 16 pins instead of 14 pins, but the 15/16 are NOT connected to the lcd backlight. They might be pretty old. Was there a different pinout before the 14pin one? Both are samsung displays. One says TM402CQ on the pcb. Any ideas?

author: macboy
author_rank: Super Contributor
timestamp: April 29, 2015, 05:23:43 pm
content: You may need to trace the pins back to the controller IC to reverse engineer the pinout for yourself.

author: nixfu
author_rank: Unknown
timestamp: April 29, 2015, 05:50:26 pm
content: 15/16 are usually for the back-light, I have never seen them used for anything else.

author: Skimask
author_rank: Super Contributor
timestamp: April 29, 2015, 06:12:55 pm
content: 40x2 sometimes have a 2nd enable pin. 1 enable gets the first 20x2, 2nd enable gets the last 20x2.

author: Pjotr
author_rank: Frequent Contributor
timestamp: April 29, 2015, 06:31:39 pm
content: Pins 1 - 14 are pretty standard. Pins 15/16 are for the back light, whether or not there is a LED back light mounted. However the polarity of pins 15/16 varies from LCD to LCD and can sometimes be jumpered for correct polarity.
LCD with no datasheet - Page 1
Forum section: electronics / projects

author: Tris20
author_rank: Regular Contributor
timestamp: April 13, 2014, 02:04:57 pm
content: I got an LCD with a Maplin goodies bag a while ago. No datasheet which combined with this being my first time using an LCD is not a good combo. Anybody got any suggestions on the pin config?

author: Tris20
author_rank: Regular Contributor
timestamp: April 13, 2014, 02:24:13 pm
content: Also, this is the kind of display I get when I put 3.3v into any one of the pins in the row you see the green wire and place my finger across some of the pins in the other row.

author: Recyclojunk64
author_rank: Contributor
timestamp: April 13, 2014, 02:36:34 pm
content: One side should be the scanning electrodes, and the other the signal-electrodes. something like the diagram on the left.A little experimentation should reveal which pins correspond to which segments.
LCDs for extreme temperature - Page 1
Forum section: electronics / projects

author: rakeshm55
author_rank: Regular Contributor
timestamp: May 24, 2018, 05:35:35 am
content: Hi,I have a requirement to used LCD display (20X4 character display) which can work in extreme cold climate.Operating temperature (-30*C to 60*C)Storage temperature (-40*C to 70*C)i have referred tohttps://www.digikey.com/en/articles/techzone/2014/dec/selecting-lcd-modules-for-extreme-temperaturesI could find just few products meeting the specificationThis could create sourcing problems in future. I was looking for a display type which is widely available.Is there any product class that meet this specification?? Any help appreciated.Thanks in advance

author: rs20
author_rank: Super Contributor
timestamp: May 24, 2018, 05:42:13 am
content: As mentioned in the linked document, have you considered OLED displays?

author: Berni
author_rank: Super Contributor
timestamp: May 24, 2018, 05:57:56 am
content: You can get tiny LED matrix displays and those will work even at liquid nitrogen temperatures and past 100°CYou can also get VFD displays in the form of matrix characters. Those will work from absolute zero and up to solder melting temperatures. So the only limitation is the driving electronics.But none of thee solutions will be as cheap, easy to implement or power efficient.

author: coppice
author_rank: Super Contributor
timestamp: May 24, 2018, 06:06:49 am
content: Why would there be sourcing issues in the future? The need for wide temperature range LCDs isn't going away. There are less options for these than for narrower temperature ranges, because they represent only a small part of the market. Even a small part of the LCD market is pretty big, though.If you choose an off the shelf panel and that particular panel goes out of production, Dave has recently made videos showing how you can get your own custom panel tooled up and ready for production for a modest cost.

author: rakeshm55
author_rank: Regular Contributor
timestamp: May 24, 2018, 08:26:11 am
content: Hi,My application was for a military grade product . So in case i go for an OLED based technology then what could be the life time of the product provided. Is OLED used in standard Mil grade products ?? I do not know... Please advicein one of the OLED data sheets its stated as""The Display OFF command can be used toextend the lifetime of the display.Luminance of active pixels will degrade faster than inactive pixels.Residual (burn-in) images may occur. To avoidthis, every pixel should be illuminated uniformly.""

author: krish2487
author_rank: Frequent Contributor
timestamp: May 24, 2018, 08:57:26 am
content: Isn't this a case where reaching out to the manufacturer yields more informative results??They can address your queries the best, isn't it?Just my 2 cents!
LCDuino (arduino) DIY audio preamp system - Page 1
Forum section: electronics / projects

author: linux-works
author_rank: Super Contributor
timestamp: May 09, 2015, 03:27:56 pm
content: showing my build of my own LCDuino-controlled audio preamp:more info here:https://www.flickr.com/photos/linux-works/16832746374/in/photostreamsummary:- audio (line in, line out) preamp and i/o selector that is arduino controlled.- learning receive-side IR (bring-your-own IR remote)- motorized pot as control element (no audio goes thru it)- telco quality latching relays used in passive R2R attenuator, 127.5dB range in half dB steps- hitachi 2x14 lcd display with LCDuino backpack module behind it- extensive customizable menu system (port names, etc)- hooks for remote-remote control (web-based, wifi, xbee)- planned integration with remote audio-video-power switchesblank boards for all that are available. all parts are easily buyable at mouser/etc. thruhole used for all boards (easy DIY). schematics, board layouts, source code and makefiles (etc) available for download.I spent a lot of time on this (as did my partner, AMB labs). we tried to make something unique and high quality, with a strong DIY focus.

author: Marco
author_rank: Super Contributor
timestamp: May 09, 2015, 06:55:31 pm
content: Very nostalgic looking, apart from those stitched ground planes.

author: linux-works
author_rank: Super Contributor
timestamp: May 09, 2015, 07:27:19 pm
content: thanks. on the motherboard there is a small digital GP and the large one behind that is the analog.having such huge GPs lets me get away with a plastic case and still not have any significant hum. (I didn't design the motherboard, though; that's my partner-in-crime's work)
LCR meter - External bias adapter - Page 1
Forum section: electronics / projects

author: plesa
author_rank: Frequent Contributor
timestamp: August 04, 2013, 07:43:13 am
content: Does anybody experience with building the external bias adapter for three terminal handheld LCR meter?I would like to build one based on schematic and part list for HP/Agilent 16065Chttp://cp.literature.agilent.com/litweb/pdf/16065-90020.pdfThere is 200V version availablehttp://cp.literature.agilent.com/litweb/pdf/16065-90011.pdfbut 40V seems to be enough for basic voltage to capacitance measurements.The most important will be 1uF 100V Polyethylene capacitor and 100u 100V electrolytic I suppose.I will appreciate any commnets.

author: SeanB
author_rank: Super Contributor
timestamp: August 04, 2013, 09:25:18 am
content: The 1u cap will be easy, polypropylene or polyester, use a 250V component and it will do with a quality brand unit like Epcos or Wima.100uF units will be harder, but the same again about brand, and use low ESR units. Would probably be better to use 400V units, as these are available with high ripple current ratings and ultra low ESR as bulk power supply capacitors.
LCR Meter, In Circuit vs Regular - Page 1
Forum section: electronics / projects

author: sacherjj
author_rank: Frequent Contributor
timestamp: November 08, 2012, 04:31:25 pm
content: I'm looking at a quality LCR meter and trying to determine if In Circuit capable meters are worth the extra money($450-600 vs $300). It seems like there would be situations where you are measuring the network rather than the component, except where things work out with isolation of the component.I'm seeing the main value of an in circuit as validating capacitors on a finished board. Anyone have real world experience with doing this? How well does it work?
LCR meter vs oscilliscope and function generator - Page 1
Forum section: electronics / projects

author: ftransform
author_rank: Frequent Contributor
timestamp: December 23, 2012, 03:22:21 pm
content: So I have an oscilloscope and a function generator. I'm thinking about a LCR meter but first I would like to know how accurate is a function generator/oscilloscope for measuring LCR?Lets say a technique like this is used:http://www.edn.com/design/test-and-measurement/4363759/Circuit-measures-capacitance-or-inductanceHas anyone done both and compared?A LCR meter is convenient but its rather specialized and expensive.And how about finding Q?Since LCR meters only go up to say... 100khz typically (for the bloody pricey ones), is a function generator capable of doing 10mhz much better? or is the difficulty of taking measurements high?rigol 1052e vs extech LCR meter

author: mazurov
author_rank: Frequent Contributor
timestamp: December 23, 2012, 11:50:24 pm
content: Q is 2*pi*f*L/R, after you know the inductance, resistance and frequency of interest "finding Q" doesn't require any instruments.As far as measuring inductors, the necessary instrument depends on accuracy you require and application. An LC circuit driven from function generator will give good approximation . Small-signal low frequency meters are cheap, large-signal are expensive but can be built ->https://www.eevblog.com/forum/projects/inductor-tester/.

author: saturation
author_rank: Super Contributor
timestamp: December 24, 2012, 02:45:16 pm
content: I do it all the time, check archives for discussion. You can approximate the function of an impedance analyzer with just the basics, that's >$30,000+ device for 'free'.https://www.eevblog.com/forum/beginners/commercial-capacitor-tester-gizmo-or-my-scope-and-signal-gen-combined/msg87586/#msg87586The only reason to buy an LCR meter is setting up the gear is laborious and time consuming and your need is to do spot checks say, on grab bags or parts salvage. For very fine measurements in impedance analyzers, the rigging matters [ fixtures, etc., clamps and cables] you'll find they often cost more than most handheld LCR meters.

author: ftransform
author_rank: Frequent Contributor
timestamp: December 24, 2012, 10:13:25 pm
content: ho ho ho merry chirstmashere is the ieee pdf on doing this operation yourself with some helpful tips

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: December 25, 2012, 04:44:51 pm
content: You can do almost anything you'd want to do by resonating with another reactance or measuring impedance manually. Accuracy won't be as good as using bridge techniques, but still plenty good enough for most purposes. You can also build a very functional bridge with just a few components and calculate by hand. You might find my impedance conversion utility handy as it does a lot of what very expensive bridges do when they format their output-http://conradhoffman.com/chsw.htm. You'll also find the circuit for a very functional capacitance bridge for large electrolytics on the same page. More useful stuff here-http://conradhoffman.com/electronics01.htm