[ID] LED type of display? - Page 1
Forum section: electronics / general

author: onesixright
author_rank: Frequent Contributor
timestamp: July 24, 2017, 10:48:34 am
content: Anybody has a clue how you call this type of display? Its on ebay and aliexpress called aarge led display clock.I'm only interested in the display. Any source to the display appreciated?Thanks!PS: to the moderator(s): isn't a separate section for component ID not handy?

author: cowana
author_rank: Frequent Contributor
timestamp: July 24, 2017, 11:26:29 am
content: Closest would be an LED Matrix display with square pixels.That one will be made from a custom plastic moulding, with individual 3mm PCB mounted LEDs mounted behind it.

author: wraper
author_rank: Unknown
timestamp: July 24, 2017, 11:56:54 am
content: Particular display on the picture likely is a custom thing with a clock controller and bare die leds mounted on a single PCB.

author: stj
author_rank: Super Contributor
timestamp: July 24, 2017, 05:33:56 pm
content: i think i'v seen those kits at banggood.go look them up - see if it uses a standard microcontroller.

author: floobydust
author_rank: Super Contributor
timestamp: July 24, 2017, 07:31:59 pm
content: It's a unique display with square pixels.I have the smaller led matrix clock, 4-digit one with DS3231. The red LED's part number is MAX-13117BUR.Oh I see it onAlibaba as KEM-13117.

author: onesixright
author_rank: Frequent Contributor
timestamp: July 24, 2017, 07:52:13 pm
content: *Square* is the keyword :-) Thanks!Searching eBay for "square pixel matrix" a few hits. Also google "mini rgb square led" does wonders.The "Adafruit DotStar" are very nice (multi color), but also very expensive. I need 2 or 3 horizontalI then ran into these, more affordable (less pretty).https://www.seeedstudio.com/8x8-RGB-LED-Matrix-Square-LED-Dot-p-1730.htmlhttps://www.adafruit.com/product/902Not bad, but not h cheap.https://www.aliexpress.com/item/apa102-addressable-led-mini-flexible-led-message-sign-board-screen/32797144408.html?spm=2114.search0302.4.2.wq1SUiThanks to all the help!

author: Zero999
author_rank: Super Contributor
timestamp: July 24, 2017, 09:18:49 pm
content: Can it display anything or is it just purpose built for a clock? If it's just a clock display, then it probably won't have pixels in places which will never be used when just displaying numbers.

author: tooki
author_rank: Super Contributor
timestamp: July 24, 2017, 09:47:23 pm
content: Many of those clock kits use a matrix of SMD LEDs, with a laser cut black acrylic sheet to form pixels, and simple paper or plastic sheet in front to diffuse. So it may not be a display module at all.

author: onesixright
author_rank: Frequent Contributor
timestamp: July 24, 2017, 10:15:49 pm
content: Quote from: Hero999 on July 24, 2017, 09:18:49 pmWel each led you can switch on/off, so in essence you should be able to.

author: onesixright
author_rank: Frequent Contributor
timestamp: July 24, 2017, 10:17:05 pm
content: Quote from: tooki on July 24, 2017, 09:47:23 pmThats indeed exactly what it is. Bunch of LED's with a driver (often some MAXxxxx) with I2C support.

author: stj
author_rank: Super Contributor
timestamp: July 24, 2017, 10:19:07 pm
content: stepping it up a notchhttps://www.aliexpress.com/item/Factory-direct-sales-P6-indoor-1-8scan-SMD-full-color-192mm-192mm-32-32-pixels-27777dots/32373468927.html

author: g0hjq
author_rank: Unknown
timestamp: July 24, 2017, 11:00:37 pm
content: I've got one of those somewhere. I'll see if I can find it and do a tear down.I think it is just a bunch of SMD Leds.

author: Zero999
author_rank: Super Contributor
timestamp: July 25, 2017, 07:55:34 am
content: Quote from: onesixright on July 24, 2017, 10:15:49 pmWhat if it isn't a complete matrix? If it's designed for a clock and nothing else, then it's possible there are no LEDs where the pixels never will illuminate when displaying numbers, such as in the holes when the number 8 is displayed. The fact the picture in the original post shows an alarm symbol, indicates this is just a clock display.It could be arranged as per my attachment. The areas with the dotted patten might not have any LEDs because they aren't needed for displaying numbers.

author: g0hjq
author_rank: Unknown
timestamp: July 25, 2017, 05:03:49 pm
content: I've got one of these, and have just taken it apart.The display isn't a full matrix - only the 7-segments of each digit, and the colon and am/pm & alarm indicators are populated with 3mm red leds.The standard of construction is quite dreadful. There are two PCBs, with a mess of bodge wires and components tacked between tracks on both sides of the PCB. There's even a dropper resistor in line with the power connector, presumably to stop the voltage regulator overheating

author: tooki
author_rank: Super Contributor
timestamp: July 26, 2017, 10:27:06 am
content: Quote from: stj on July 24, 2017, 10:19:07 pmSpeak of the devil! I just wired up the 64x32 RGB panel I got off Ali. (I got a P4, though, not P6.) Gonna have to try it on an arduino due, though, a Mega256 struggles to update it quickly!P.S. Your URL got truncated, it's missing the L in .html

author: Zero999
author_rank: Super Contributor
timestamp: August 08, 2017, 10:23:20 am
content: Quote from: g0hjq on July 25, 2017, 05:03:49 pmThat's pretty much what I imagined would be inside it. Did you manage to re-purpose it?QuoteThat's perfectly fine and is good design practise. A dropper resistor in series with a linear regulator is a fairly standard way to reduce the power dissipation in the IC. If there's a reasonable sized smoothing capacitor at the input of the regulator, it will also improve the ripple rejection too.