How to identify the contacts of an LCD connector?

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SUMMARY

This discussion focuses on identifying the contacts of a bare LCD screen, specifically the 16x2 LCD module (ADM1602K-NSW-FBS). The user sought to access all dot matrix pixels after separating the panel from the PCB, requiring knowledge of ground contacts and segment driver connections. Key insights include the necessity of a complex analog drive scheme for LCD panels, which often require multiple voltage levels, as detailed in the HD44780 datasheet. The user ultimately succeeded in their project by using conductive glue to connect faintly visible contacts after extensive trial and error.

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PhysicoRaj
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Hello all,
I needed a bare LCD screen without the driving circuitry for my project. So I opened up the 16x2 LCD module (https://www.sparkfun.com/datasheets/LCD/ADM1602K-NSW-FBS-3.3v.pdf) and separated the panel from the PCB.
Now I have the panel with the ZEBRA connector hanging from it.

Basically I need access to all the dot matrix pixels at a time, which can be used for various purposes in my project.
How do I know which is the ground contact and which contacts come from the segment drivers (row enable? column enable?) and which of them are active low?

Any help appreciated,
Thanks.
 
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PhysicoRaj said:
How do I know which is the ground contact and which contacts come from the segment drivers (row enable? column enable?) and which of them are active low?

all that info is in the datasheet you provided
pages 8 - 14

I would suggest that you are going to have a VERY difficult time using the panel without its drive

what are you trying to achieve ??Dave
 
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LCD panels need a fairly complex analog drive scheme. The output of the driver has multiple voltage levels that need to be cycled in the correct order.

https://www.sparkfun.com/datasheets/LCD/HD44780.pdf

This particular one uses up to 6 different voltages to drive the panel. I would suggest finding a micro-controller with built in LCD drive. Many of the usual manufacturers make them.

As to determining the pinout you will either have to find a datasheet online somewhere for bare glass or examine the one you have. The conductive traces are usually faintly visible.

BoB
 
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It's been quite too late but just thought of ending this saying I worked it out with monstrous efforts for the past two months, trialing out different combos of pins for selecting rows and columns.
Ended up using conductive glue for the 'barely visible' contacts!
Anyway it completed my painful 3rd year project. Thanks for your help.
Cheers.
 
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