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- เผยแพร่เมื่อ 12 พ.ค. 2024
- Part 1 in a series of videos on designing a custom LCD display.
This tutorial covers how LCD displays work, the 3 different types of interface (DIP, Elastomeric, Flex), the three different optical types (Reflective, Transflective, and Transmissive), and the two different types of drive (Static vs Dynamic)
Microchip AN658
ww1.microchip.com/downloads/en...
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very useful tutorial, thanks Dave, looking forward to the next part :)
Excellent video, just in-depth enough to explain the differences, looking forward to the rest of the series
5:38 Funny case in fact about LCD's being sluggish when cold, my mom's car has an LCD displaying (among other info) the outside temperature. When it gets near or below freezing, the temperature indication will blink to alert you to that. Except that precisely because it is cold, the blinking will be almost unnoticeable since the indicator hardly fades before it comes back on again.
There is a video about the Gameboy DMG LCD. Strobe light or a fast camera shutter show that it flickers faster than the human eye can see. Do Gameboys fail in winter?
@@ArneChristianRosenfeldt They won't fail just from a low temperature. The cold will negatively affect the screen's responsiveness, causing what is called ghosting. You will see an after image when something disappears from the screen, or a fading trail behind something moving across the screen. But this effect disappears when the display is warmed up again.
@@MicraHakkinen good thing that the liquid is not water and can’t break stuff as it freezes. I was just wondering: I know the ghost of the cursor on Ti Z80 based calculators, but there is no ghost on Gameboy.
This is exactly what I expect from your channel. A way to learn electronics, combined with your experience, not seen in any other channel. A bit of stuff for the beginner, a bit of new stuff for the experiences. Great subject!
Thanks Dave! Looking forward for the next parts of the series!
I've always wanted to know how to get custom lcd displays made. Looking forward to the other videos!
I love his enthusiasm! It's so adorable and makes me want to learn more
That was an excellent video Dave!
Dave, I loved this, thank you. I had to wait for the right day to watch it and pay attention properly, but this looks like being a really good series, thank you.
Thanks Dave. Looking forward to next video in the series. Very interesting topic.
Same. I want an LCD for my multimeter!
@@GRBtutorials hi, if you need an lcd, welcome to contact us at: www.szmaclight.com
Great tutorial! Looking forward to the future videos in the series!
Super useful, always fabulous learning how to do stuff & LCD displays are things I have stayed away from as there are so many possibilities, but this series looks like it will really help me get to be able to confidently use these lovely things. Thank you!
Dave, a tutorial on the multiplexing biasing would be great.
Thanks much. It was great to learn about the different types. Looking forward to following the series and learning more.
Yes! I've been waiting for this series. I've been wanting to experiment with LCDs for a while, plus I got a Raspberry Pi Zero (and RPZW) coming in the mail. Can't wait!
Oh man this is great, can't wait for the part about designing a custom one, I've always wanted to do that!
Another presentation (style and content), many will want to emulate. Dave Jones, the educator!
Cheers.
Great video, very interesting. Looking forward to the rest in the series.
I sometimes used "simple" LCDs directly connected to a micro. You can do that without burning out the display by generating the AC in software. Connect both the common and the segments to GPIOs. Set the common to high and the segment to low and reverse that every 1/100s using an interrupt. To turn off a segment set its GPIO to the same logic level as the common (so no voltage across that segment, even if both the common and the segment change level every 1/100s). With clever programming you can even drive multi common displays this way.
There is a video which shows flicker on a Gameboy DMG. Can you let a passive LCD flicker faster than the eye can see using software?
Awesome tutorial Dave.... looking forward to the next episode.....
very informative. loved it.
This video is no less than a blessing for me as i am working on these displays these days.
Cant wait for the next videos.
Thanks.
I was looking for the second video, then I realized it was published yesterday! I'm finally caught up. I thought this day would never come.
Super video, thanks, Dave! Some overview and then making an actual device is the best type of video for hobbyist like me :)
I still find it absolutely amazing that LCDs are in everything from cheap calculators to 100" 4K Dolby Vision enabled TVs. You don't get that kind of scaling from any other display technology.
I know it's pretty much common sense that we're surrounded by plastic. But I had the same sense of sort of awe (and horror) when I looked around my house and struggled to find anything that didn't have plastic of some sort in it. The only things really were things like seashells I collected, and maybe my dry wall? Oh and I guess my clothes... well except for the buttons and probably tags. It's mind boggling to realize I'm not just surrounded by the stuff, it's in literally EVERYTHING I own. I feel like this is gonna be one of those things we look back on in the future and say "wtf were they thinking?"
Like we do with victorian practices. Like using tobacco smoke enemas to cure drowning. Seriously, they actually had rescue kits to do this set up on the Thames. Or using benzene as an aftershave, when we now know it causes leukemia. And the classic opium and cannabis tincture for your baby when they won't sleep. Probably because they're addicted to opium. Not to mention the horrible adulterants that were added to food. There was a book of advice for housewives that suggested adding borax to sour milk to mask the sour taste so you can keep drinking it longer. Wasn't Victorian England so magical? lol
This big single digit LCD (or a similar one) was used in a clock circuit published in one of these electronic paper magazines. I think it was elektor. It was 10+ years ago. Point is: Since they are static they just used 74HC595 or 4094 (can't remember exactly) to drive all the segments. The common pins were tied together and driven by something else. The microcontroller had to do the AC switching of course. The display is so big that it was no problem to hide the DIL ICs underneath it.
Well, you actually can drive a simple LCD display with common microcontroller GPIO if you need. Just drive the common electrode and inactive segments low while driving active segments high for 100 ms then switch everything by inverting the output: high on common and inactive and low on active segments for another 100 ms. That way you generate AC square waveform with no DC component relative to the common LCD electrode.
How can this trick work in case of large number of segments where you run out of GPIOs to drive each segment individually?
@@gauravsingh84for starters, a lot of these don’t have one common electrode, but a matrix of rows and columns. At least logical, even if not laid out as such. Then if you pay enough you get a ton of GPIO . Enough for segment LCDs. Not enough for Gameboy DMG.
Amazing video Dave! Can't wait for the next ones :)
This is a great video, love to see this type of content dave!
It's actually possible to drive the through-hole type (the simplest) LCDs using GPIO output pins by reversing the drive polarity in a loop (I used a 4Hz timer). I used a TI MSP430F2272 micro-controller that had all the required GPIOs.
Good intro to LCDs. I package these displays into our products at work but not being a circuit designer it's nice to pick up the basics here. I hope you are going to cover how to interface these with micro controllers and give some cover to font sets to use. 5*'s Dave!
Loved this video, thanks Dave!
Good vid, Dave. Keep up the good work.
Great video, thanks Dave! We want more content from the junior Dave as well please.
Wonderful description!
Great video Dave!!! Very informative and interesting!!!
Love your instructional videos. Always learn something.
Very useful video, it helps a lot. So easy to understand even for non Aussie listeners.
Great tutorial Dave.
You tease! You get me excited for designing a LCD and now I have to wait.
:(
love this kind of video, good topic, very informative, so worth the watch.
Great video, looking forward to the rest of the series. I wonder why a channel like this would have it's videos demonetized though.
Good things come to those who patiently wait. :) Thank you for an awesome video!
Nice video! Looking forward to see the next one 😊
Thanks for the video. Ever since I pulled apart things as a kid I've always wondered how LCD's were actually driven. They've been a mystery up until now :).
Thank you for a cool educational video, Dave!
An interesting topic Dave well done.
Hi, Dave , great video, very informative, I will recommend it for reference.
Dave, it would be great if you can do a video on the operating hours and life of these LCDs.
I love starburst displays too, and share your unabashed expression of glee.
good tutorial please keep going on with LCDs
Awesome video, looking forward to more.
More tutorials like this please !
That was a great tutorial on LCD display types. Spot on and makes understanding of these items so much easier
+Bruce Woods glad you liked it
Excellent explanation!
Great video, I thoroughly enjoyed it, thank you!
do a tour of an lcd factory. i really liked that interview with those Aussie calibration engineers.
+TheAstronomyDude I would if there was one in Australia?
You could perhaps get more success from SerpantZA, though I doubt it - he figured out where youtube get their Silver Play Button awards manufactured locally to him in China and tried to get a factory tour even turning up at the factory gate th-cam.com/video/4EL4xBxc5IA/w-d-xo.html
fantastic video. I really appreciate this type of tutorial.
Third time's the charm, eh Dave?
That really small character LCD is actually used in one product I own, and one I want to own. the TNS-HFC5 Famicom cartridge and OSSC line doubler both use it in its I2C form as the AQM0802 (8 x 2) A or GW (backlight). It's a pretty nice little screen.
Dave is full powered today hahaha
thanks for posting
Great video thanks for posting
Those bare LCDs are a pain to drive without a driver chip. I find it much easier to salvage a VFD from something, than to get a random LCD working.
I do like using the old 84x48 Nokia LCDs in projects though, they are dirt cheap and simple to drive over SPI.
I really like where this is going! :)
Yess!
This is the kind of videos I want :)
Njoyed these!
My mom had a 16 segment display on a Hifi and I always sat in front of it watching the text scroll. Amazed.
Very clear video tutorial!
OMG yeeeeeeaaaas I've been wanting this for ages!!!!!!
Awesome video!
That. Was. Awesome!
This just took a lot of mystique out of the world, but it is very cool to see that simplicity was always there.
Awesome! Will you do one on OLED displays too? Maybe do a teardown of one also?
Thanks!
This is wonderfull
Wonderful video! This is what I personally like ^_^
I have the Display'o'tron Hat for the RasPi, from what I understand this LCD is a COG type, already mounted on a PCB board for convenience. It uses the serial i2c bus on the GPIO but i think it supports other modes too, i'd love to learn how to interface with this directly instead of using the python library.
I would love more information about the diferent Bias and how to design with a FPGA our own driver, some display with not to much segments.
Thanks for you videos! :)
3 commenters here drive LCD using GPIO on a uController. So it should be easy with FPGA. Just buy a model with lots of pins .
Thanks a lot for your video about displays. I am just disappointed that most displays used in DIY projects are simple few segments LCD or up to 640x480 displays. I would however like to use smartphone displays having much higher resolutions for displaying good quality images. those displays are mainly driven by the MIPI standard. I am still looking in ways to interface those displays with simple microcontrollers and by using an intermediate graphic driver having a frame buffer. The microcontroller would just fill the frame buffer (for picture display , low refreshment would be ok) and the graphic driver would control the "smartphone" quality display accordingly. Maybe this could be an interesting subject for a future video.
You can buy microprocessors that do all of that in a tiny package for about two bucks.
Ben Eaters worst video card shows how to read out a frame buffer and send serial data without blocking a CPU.
Cool! I have a raw glass LCD. Have no idea where I got it, had no idea how I would use it, and still wouldn't use it since I have to drive it!
interesting as always
I learned alot thank you.
Good video!
Really liked this great vid. :)
you make my day
ps.from croatia with love
Wow cool video !
G'day mate, love it when I click on a random TH-cam video and it's another Aussie
Thanks!
please do a series on camera devices or camera sensors also
awesome video btw waiting for next one
I'm new to electronics so I love watching your videos to gain knowledge. The only thing I don't understand is, if dc voltage will kill lcd's after a while, than how do calculators use lcd's?
The same way as any other app. having a LCD. The calculators control IC holds an AC driver circuit.
MrJetra thank you for responding!
You're wellcome. If you are capable of reading a datasheet, you could try the Microchip PIC16F916 microcontroller. In section 9 there is a description of different LCD drive modes.
Off topic, I dig the chart behing you in the around 1:00 into the video. Please provide a bit of info on it.
great video, Did not know that there was this many types :D
There are more.
Very nice!
💚💚💚💚 bookmark/ notes: 11:14 strip / eraser pressure for the changing lcd …..ect……tbc….-g-b, bot
dave, use 2 of those large number lcds for a house number display on your front door!
Thanks for that video! What would be also very interesting to see a comparision between LCD and TFT.
How is the readability between LCD and TFT under daylight conditions?
Is an LCD still the best readable display for outdoor products?
Lots of motorbikes are switching to TFT-Cockpits but I'm not sure if these are transflective TFTs?
Technically, TFT's *are* LCD's, but unlike LCD's, they *require* a backlight. TFT = Thin Film Transistor, where each pixel (or do they have them with segments too?) has an associated transistor that turns it on or off, thereby blocking the light coming from the backlight, or letting it through.
so its not possible to make a transflective TFT?
I doubt. The transistor layer would damp the incomming light so much that it would be practically unusefull. You need to take into account that the transistor layer is located on the inner side of the rear glass plate (where the LC liquid is). The reflector is placed outside. The light must pass the transistor layer twice.
thank you very much for the explanation!
Very useful .. Thanks !
One thing I have always been curious about with both LCD and LED 7-segment number displays: why do so few of them have the "bottomless" 9s, while most use the bottom segment with their 9s? I think the bottomless 9s look cooler (although I can see why you'd avoid the topless 6s, as they might be mistaken for a b, or vice versa), and it seems they would save power?
Great intro! Two questions about defects: 1) Is a black, distinct irregular blob the LC fluid leaking? 2) What is/causes a round-ish fuzzy "burn" spot?
That that would be leakage. No fixing that.
In some cases reflective LCDs can be backlit but only 5~20% of light may pass through the reflective layer. Just use other types of LCD, such as transflective LCD!
That's probably a shit reflective display then!
EEVblog
Very common in Chinese displays! :)
Yay new video
Great video!
How would one go about to get a replacement lcd?
I have an old electric surface plane meter with a broken display. I have had zero luck finding anything remotely like it when googling for replacement displays.