My quest for a cheap LCD for Neato XV!

[LionTamer]

Hello All

I was asked by a customer to repair a Neato robot with dead display and after finding and reading the thread I decided to spin a replacement display PCB for the machine with requirements as follows:

Drop in replacement for Binky Rev 4 PCB
2.5" display rather than mod in a smaller 2.2"
No hacking or cutting of the case if possible.
No daughter boards or bodge wires.
No having to manually flip the LCD.

I may be a bit of a glutton for punishment but as you can see from the photos below I succeeded, I could not get a display of the right size with the I2C connection available so instead I used a PIC18F27K40 to convert the I2C to parallel and then used an EastRising ERC128128FS-1 . The edge bleed on the right hand side is probably due to slightly more pressure on the LCD as the screen is slightly thicker than on the old one.

Old PCB and New PCB Front View

Front View
Left: Old PCB
Right: New PCB

Old PCB and New PCB Rear View

Rear View
Left: Old PCB
Right: New PCB

Fixed Neato

Fixed Neato

As a result I have also got 6 spare blank PCBS here which I can sell on either as populated (I only have one spare display so would have to get more if people wanted them) or unpopulated boards. If there is a lot of interest then I may even be persuaded to run a batch of boards.

Jem

[nietzsche]

Hello guys

a few weeks ago my Neato also started showing this issues. My first try so far did not fully work because I've ordered a too cheap fpc-to-dip board, which missed some pcb traces (or they fell of due to the multiple (de)soldering). But I was able to get a picture on the replacement display for a short while using breadboard. Now I am waiting for the next bunch of replacement parts to give it another try.

Additional questions I have:
Is it possible to also use the invert image function of the the display with IIC? I was reading the datasheet of the display controller but I wasn't even able to locate the function FuzzyLogic used on page two of this thread. I understood it like this, that the controller has no persistent flash for the settings and that this option has to be set every time the display is turned on?

I ordered the same ERC128128-3 displays, but mine don't seem to have this transflective layer. After I remove the backlighting pane I see a gray layer with another transparent foil on it. While the foil is removable (not that easy though), the gray layer isn't. Because of that I messed up my first two displays. So what exactely is this transflective layer? My displays don't seem to have this foil shown on the first page of this thread.

Thank you very much

[tlt]

Hi, thanks for this guide, it saved my Neato!
I used the same display as the original author but I made a castellation PCB (a PCB that have an edge that can be soldered to another PCB) that I soldered to the control board where the flex cable was. It is extra thin (0.8 mm) to fit and has a footprint for a 31pin FPC connector (XF3M-3115-1B-R100). This method could give a clean looking installation of the display but mine became a bit ugly because of damage on the solder mask from previous failed attempts while developing the PCB. I hade to file some to open the vias on the edge of the adapter board so that they could be soldered to.

You can order the PCB on OSH Park

If you like to modify it the Eagle files are on github

[mfortuna]

I just noticed this updated thread. Impressive work by both of you.

[cav1452]

Looks like amazing work, I would gladly pay you for one of these if you still have any available.

Hello All

I was asked by a customer to repair a Neato robot with dead display and after finding and reading the thread I decided to spin a replacement display PCB for the machine with requirements as follows:

Drop in replacement for Binky Rev 4 PCB
2.5" display rather than mod in a smaller 2.2"
No hacking or cutting of the case if possible.
No daughter boards or bodge wires.
No having to manually flip the LCD.

I may be a bit of a glutton for punishment but as you can see from the photos below I succeeded, I could not get a display of the right size with the I2C connection available so instead I used a PIC18F27K40 to convert the I2C to parallel and then used an EastRising ERC128128FS-1 . The edge bleed on the right hand side is probably due to slightly more pressure on the LCD as the screen is slightly thicker than on the old one.

DSC05642.jpg

Front View
Left: Old PCB
Right: New PCB

DSC05643.jpg

Rear View
Left: Old PCB
Right: New PCB

DSC05661.jpg

Fixed Neato

As a result I have also got 6 spare blank PCBS here which I can sell on either as populated (I only have one spare display so would have to get more if people wanted them) or unpopulated boards. If there is a lot of interest then I may even be persuaded to run a batch of boards.

Jem

[AlainCAN]

Hi every body,

First of all, congratulation for your very nice work.

Today I only would like to share with you that you can waking up your blank LCD screen only with the addiction of a wire !

I have 3 Neato XV, one of them got this issue, so I decided to open 2 of them, the broken one (blank screen) and a working one. With the oscilloscope I found that on the broken one, the VOUT pin was above 8V, on the working one, VOUT is about 15V.

After a deep reading of the LCD's datasheet, I decided to wire VOUT to the input of one voltage regulator on the main board, I cross all the finger I can cross then I push the start button and ... The screen was displaying the wonderfull Neato's logo again.

Total cost of this repair : 0 euros (or dollars or pounds etc...)

This is what I just tried now, I will survey that the LCD's chip won't be burned by the injected current on VOUT. I will let you know the final result in few days.

My suposition is that the internal resistors (onchip) used for the internal voltage regulator are damaged and the voltage regulator (internal) is now not able to give enough voltage for the LCD.

Once I will understand how to post a picture, I will upload the pictures of this wiring.

With all my respect to your job, I hope that this will help somebody.

Please remeber that this voltage injection to the LCD can damage the robot or in the worst case, put it in fire, that's why I decline any responsability with this manipulation if somebody do it too. Do it at your own knowed risks.

[AlainCAN]

Ok, Good news, it didn't take fire in my house and let's say that in fact, you will need more than one wire, there is no 12V regulator on board, so you have to add one (you can find some very cheap on eaby, at ~3 euros.).

After some measurment, the VOUT pin on the LCD display is about 17.80V when the battery is fully charged and the robot is at the base station.

Here is how I repair it :

First of all, the very nice blank screen

The wonderfull blank screen

To repair it without changing the LCD, you will need :

- a Red wire
- a Black wire
- a green wire
- a Power Regulator like this one : https://www.ebay.fr/itm/LM2596S-Module-DC-DC-Step-Down-Ajustable-Module-Abaisseur-Regulateur-de-Tension/263330885857?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3D1df35fca2b144204a915a9f38cb26a2a%26pid%3D100675%26rk%3D5%26rkt%3D15%26sd%3D201125671881%26itm%3D263330885857&_trksid=p2481888.c100675.m4236&_trkparms=pageci%3Ad988c03e-c3cd-11e8-9edb-74dbd18038e1%7Cparentrq%3A24c17bf91660ac88c2ccd32cfff6f962%7Ciid%3A1
- a double tape rubber glue
- an antistatic plastic (simply use the one you will receive with the DC-DC power board)
- Some talent

1 - Remove the batterys of your robot, and open it.
2 - unscrew and unplug the LCD board.
3 - you will have to solder the green wire on the capacitor C5, the side closed to the LCD ribbon cable like this :

C5 Green wire soldered

Yes I now my capacitor are very sadly soldered, before to find out the issue with VOUT, I tired to replace some capacitor, this was without any effect.

4 - Solder the red and black wire on the main board, the red wire goes to the first pin of U23, the black wire on the capacitor C143, side closed to the plastic like on this picture :

PowerWire

5 - Solder the other side of the red and black wire to your power PCB (black is -, red is + ) like this :

Power DC Board

6 - STOP NOW AND READ CAREFULLY : Now, you will have to adjust the voltage regulator, DO NOT connect the green wire to the Power Regulator now. Place your battery back and place your Robot in charge and wait until the 100% charge of the battery, you will measure about 24V on the Power PCB input (between the red and black wire). Use a screw driver to adjust the ouptut voltage to 14.0V, you must stay at the charging station while doing that to ensure that you receive the 24V coming from the charger.

Why 14.0V ? I read the LCD datasheet and see that this value is inside the accepted power input for the VOUT pin.
We can set 17.80V like at the origin but it will perfectly work like that with 14.0V and we limit the current.

7 - Now, remove again the battery, take the robot and you can solder the green wire to the + output of the power regulator (like on the picture above).

8 - We have now to corretcly place the power regulator inside the robot. Use a piece of double tape rubber that you will glu on the two chip U11 and the one in front of it like on this picture :

RubberTape

9 - Glu the antistatic plastic on it and add another piece of rubber on it :

AntiStatic plastic and rubber

10 - Place your DC Regulator on it :

Power DC Board in place

11- Place the wire in manner that they will not be scratched by anything while closing the robot, place your battery, Enjoy !

Unblanked Screen

You will need to adjust the contrast because the power source is not 17.80 anymore but lower (14.0V).

I don't know how long it will work but at the moment, it works.

Hope this will help you guys.

By the way, don't forget to replace the C10 capacitor as it can cause trubbles later (dimmed light green led).

[Parschulke]

Is it possible to that on a Cruz Board?

Which voltage regulator needs to connected?

[AlainCAN]

Hi,

good question I never had this board, can you please post a picture from it ? if the screen is the same, the solution will be the same too !

[neato58]

Hi,
I have limited knowledge about this and this is my first time.
I need some help with this NEATO XV-21.
I ordered and used the PCB on OSH Park and the LCD
ERC128128FS-3 from ebay.

But it wasn't successful, See pictures

[tlt]

First try to reduce the contrast in the settings menu. Looks like you managed to solder the connect on fine. The adapter PCB is suppose to be on top of part of the exposed traces and it looks like you have a gap on the left side. The vias on the edge needs to be cleaned from copper left from the cut and the traces on the control PCB has to be wicked clean from solder before attaching the adapter. Maybe try to fix it without taking off the adapter board first as that might damage the boards more, test connectivity on the left side and see if you can patch it up some how.

[neato58]

Here are two more pictures. I thinks these pictures are closer and cleaner.
Maybe this can tell more.
I checked continuity between the adapter and the board, they are all good.
When going to the contrast menu settings, up or down seems not to make any difference.

[tlt]

I can't see what is wrong from the photos. The connector has the contacts on the bottom side? Otherwise you would not see any picture at all I guess. If there is continuity and no shorts between traces that should not be connected, maybe the display was damaged when it was flipped.

[neato58]

Yes, the connector has the contacts on the bottom side. To make sure, I did flip it and had no picture.

I think I will order a second LCD and see. Thanks!

[Chipwidget]

Hi all, just posting to register my thanks for the information on this site. I have little previous experience of this sort of repair but by carefully following the instructions of Tris and DucLeto I now have a working Neato again. It was pretty nerve racking at times and tested my soldering skills to the limit but it all works! The display is not perfect, it is overlaid with a kind of hexagon pattern like bee hive cells in a pale grey colour but the text is still perfectly readable so I can live with that. So, if you are considering trying this repair I recommend you give it a go. After all, worst case is you buy a new board which is what would happen anyway. Thanks again to all the contributors here.

[neato58]

Chipwidget, Could you post pictures of this overlaid hexagon pattern. I am trying to see what is wrong with my LCD.

[slybas]

Hi,

good question I never had this board, can you please post a picture from it ? if the screen is the same, the solution will be the same too !

Neato vx-15 Cruz lcd Board.

Hello guys this forum is excellent reading, I was already ramping up to order a buckconvertor on eBay and try the shortcut AlainCAN provided but my board is a Cruz. So here goes nothing this is the connector side maybe the trick will work aswel.

I tried the open machine with the batteries and turned it on if I wiggle my finger on the c1 to c4 range I get a working picture (Battery low), but it is no use vacuuming with my finger attached

with some experimenting and a resistor I have not a clue wat is going on with the LCD, I don't know why this even works

resistor c8 to c3

.

result

"working" display

[neato58]

I got it to work. I removed the ribbon cable a few times, tried a new LCD, I put back the firs LCD that was too dark and this time the text was clear. I am not sure what happened.

[AlainCAN]

Neato_vx-15.JPG

Hello guys this forum is excellent reading, I was already ramping up to order a buckconvertor on eBay and try the shortcut AlainCAN provided but my board is a Cruz. So here goes nothing this is the connector side maybe the trick will work aswel.

Hi, I was facing the same thing with the capatitor and also already did a try with the resistors, this capacitors are here to create different voltages level for the LCD. There are not in question, the only issue is the internal voltage regulator from the screen that become defect. What voltage did you measure on C6 (ribon cable side) when the screen is on ?

[slybas]

Sorry for the delay, I had to disassemble the machine again the C6 measures on the display ribbon side 7,3 V. And while I am at it. Desoldering my attempts to have some stripy image and decided to blast the Cruz C6 with 12 V et voila. Why didn't I do this a once ! Thanks for the tip. @AlainCAN

C6 with 12v using my dime converter who is not up to scratch against 24volts

Normal image ! Like new. Up top the to small convertor