What type of LCD display connector is this? - Page 1
Forum section: electronics / projects

author: danbr
author_rank: Contributor
timestamp: October 31, 2016, 01:59:21 am
content: Hi,In a recent dumpster dive I found a nice 18.5" photo frame display. After checking the display still functioned I tore into it so I can - of course - hook it up to a raspberry pi.Although I'm a but confused at this display connector. Its a 2x10 header connector with not all positions filled. I'm unsure if its a LVDS connector, or perhaps a EDP connector? The chip directly below the header pins for the display is labeled "1154 GM8283C" Googling results in a Chinese/Japanese datasheet that I cannot read. Its translated title is "28-bit programmable data strobe transmitter". There is mention of LVDS, but this connector is a bit odd.Most of the "LVDS to HDMI" boards out there use the 30(40?)pin flat ribbon cable. The display is model M185PW01, searches for M185 return LCDs for a dell display and have the regular looking flat lvds connector. Any ideas?Interesting note: The backlight inverter board is quite small looking, I'm wondering if its a LED backlight and not CCFL since there is a single connector to the back light, with two small-ish gauge wires.Thanks !

author: Cerebus
author_rank: Super Contributor
timestamp: October 31, 2016, 02:22:18 am
content: The physical plug is a very ordinary header type and doesn't really tell you anything. So, not a "standard" connector for a certain type of panel but just what they fished out of the parts bin that suited the design at hand. The presence of several twisted pairs and some non-twisted, non-paired wires makes me strongly suspect LVDS + power (including possibly some awkward LCD power rails at 'weird' values such as -7 and +16). If the board is still working at all try metering out some leads and if the voltages on the twisted pairs are in the right ballpark for LVDS then slap a 'scope across them and it will be blindingly obvious if they are differential pairs.As to the "inverter" board - try and check the voltage rating on the caps. That's going to be a big hint as to whether it's powering some LEDS or a CCFL tube.

author: bktemp
author_rank: Super Contributor
timestamp: October 31, 2016, 07:30:13 am
content: Looks like single channel LVDS (4 data lines + 1 clock line)Could it be similar to M185XW01 1366x768 18.5" TFT LCD with LED backlight?

author: danbr
author_rank: Contributor
timestamp: October 31, 2016, 01:40:49 pm
content: Quote from: bktemp on October 31, 2016, 07:30:13 amYeah, that is a similar model number, and I do believe that is the correct resolution.Quote from: blueskull on October 31, 2016, 07:35:46 amThanks for the confirmation on the LVDS and LED back light. I'll start shopping around for a converter board.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: October 31, 2016, 02:26:04 pm
content: On a related subject, you can get LCD testers really cheap from Aliexpress, complete with a bunch of cables e.g.https://www.aliexpress.com/item/Free-shipping-New-upgrade-Laptop-TV-LCD-LED-TEST-TOOL-KIT-SET-LCD-panel-tester-Support/1551320654.html?s=p&spm=2114.01010208.6.1.vwKqsbI

author: Cerebus
author_rank: Super Contributor
timestamp: October 31, 2016, 03:45:35 pm
content: Quote from: mikeselectricstuff on October 31, 2016, 02:26:04 pmWell worth knowing. Thanks.

author: janoc
author_rank: Super Contributor
timestamp: October 31, 2016, 06:30:37 pm
content: It even comes with its own "DRM""IMPORTANT: Do not dismantle, after the demolition of the digital tube display 88 machine automatically locked, you can not use, do not disassemble the enclosure"Have you actually used one of these, Mike? I somehow doubt that the LVDS cable pinouts are standardized among panels, so I would love to hear from someone who used one of these.

author: bktemp
author_rank: Super Contributor
timestamp: October 31, 2016, 08:07:46 pm
content: The pinouts aren't standardized, but lets say 80% of the smaller panels have the same 20pin pinout.What is D6, D8, S6, S8?My initial guess was S= Single channel and D= Dual channel LVDS but that does not make sense since 1920x1200 has S8, but 150MHz pixelclock is impossible for single channel LVDS. So my only guess would be JEIDA and VESA bitorder (LSBs in first or last data line).What is inside the tester, a small FPGA?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 01, 2016, 01:06:10 am
content: Don't know what's in it but I'm of to Shenzen in a minute & might pick one up if I see one