Guide Run GreenYi Screen Off 5v

[TheGuy504]

*NOTE: NO MODIFICATIONS HAVE TO BE DONE TO GET THIS SCREEN WORKING OFF OF 5V. IF YOU FOLLOW THE STEPS ABOVE, A TINY BIT LESS CURRENT WILL BE DRAWN TO SAVE BATTERY LIFE.

*Check out
https://bitbuilt.net/forums/index.php?threads/running-screens-off-lower-voltages.2256/ if this is not your exact driver board.

*Link to screen: https://www.amazon.com/GreenYi-Vehicle-Monitor-Display-Cameras/dp/B072FNQQXV

 

[ThePuffpuff30]

Might be helpful to specify exactly what driver board this is for in the title

 

[pmarcum]

I am making a mobile display to run off of a 5-volt battery pack, and I was absolutely thrilled to find your post, as the TFT LCD monitor pictured is the exact model that I have. I've never hacked into such a thing before, and I have a couple of questions that will likely seem trivial to anyone with experience doing this kind of thing:

(1) Your post indicates completely removing the XL1509 black component. I'm assuming I just melt the solder on the 8 legs and pull it off the board. Do I need to replace this area with anything to complete the electric circuit, or does the circuit just (somehow) bypass this area when the XL1509 component is not there?

(2) Just below the XL1509 on the board is a little grey/white plastic mini-connector with a black and red wire coming from the "+","-","Menu" buttons on the backside of the monitor. After the modification, do I just plug that mini-connector with the black/red wires back in, or are these 2 wires the ones that get attached to the area in the lower middle of the board indicated in your picture?

(3) Just below the black/red mini connector is a larger mini-connector (the plastic thing in the lower right corner of the board), where the red,black,yellow, and white wires enter from the external wiring cable. After the modification, do I just plug that mini-connector with these 4 wires back in, or do the yellow/white get plugged in there but the red/black wires get moved to the area in the lower middle of the board indicated in your picture?

(4) Speaking of that area in the lower middle part of the board indicated in your picture where the 5 volt black/red wires should go: Do I just solder them into those holes or is there a more elegant/correct way of "wiring" them to that position?

In summary: I'm not sure which set of black/red wires get moved to that new lower/mid-board position (from the red/black wires in the smaller or from the larger mini-connector?), I don't know if I need to add any straight wiring to the board to "complete the circuit" after the XL1509 component is removed, and I don't know if soldering the red/black wires to the new lower/mid location of the board is the correct way to attach them to that new position. Thanks in advance for any advice/help!

 

[TheGuy504]

I am making a mobile display to run off of a 5-volt battery pack, and I was absolutely thrilled to find your post, as the TFT LCD monitor pictured is the exact model that I have. I've never hacked into such a thing before, and I have a couple of questions that will likely seem trivial to anyone with experience doing this kind of thing:

(1) Your post indicates completely removing the XL1509 black component. I'm assuming I just melt the solder on the 8 legs and pull it off the board. Do I need to replace this area with anything to complete the electric circuit, or does the circuit just (somehow) bypass this area when the XL1509 component is not there?

(2) Just below the XL1509 on the board is a little grey/white plastic mini-connector with a black and red wire coming from the "+","-","Menu" buttons on the backside of the monitor. After the modification, do I just plug that mini-connector with the black/red wires back in, or are these 2 wires the ones that get attached to the area in the lower middle of the board indicated in your picture?

(3) Just below the black/red mini connector is a larger mini-connector (the plastic thing in the lower right corner of the board), where the red,black,yellow, and white wires enter from the external wiring cable. After the modification, do I just plug that mini-connector with these 4 wires back in, or do the yellow/white get plugged in there but the red/black wires get moved to the area in the lower middle of the board indicated in your picture?

(4) Speaking of that area in the lower middle part of the board indicated in your picture where the 5 volt black/red wires should go: Do I just solder them into those holes or is there a more elegant/correct way of "wiring" them to that position?

In summary: I'm not sure which set of black/red wires get moved to that new lower/mid-board position (from the red/black wires in the smaller or from the larger mini-connector?), I don't know if I need to add any straight wiring to the board to "complete the circuit" after the XL1509 component is removed, and I don't know if soldering the red/black wires to the new lower/mid location of the board is the correct way to attach them to that new position. Thanks in advance for any advice/help!

Before I answer your questions, What are the parameters battery pack are you using? The screen draws a max of .325 amps, and I just want to make sure you will have a good battery life.

(1) No, once you have removed the component, you don't have to replace the the area with anything. Don't let any of the pads where the component was short out.

(2) You just need to plug in the connector leading from the button control board into that white slot.

(3) Don’t plug the 4 prong connector in with the red wire still attached because that is a 12v input. Cut that red wire and then plug it in. You can keep the black wire connected. The black spot is just another place to get ground on the board from.

(4) You can solder wires directly to the holes. Just be careful to not short anything out. I would recommend securing the connections with hot glue once you're done.

Once the component is removed, you don't need to do anything. Solder a wire from the positive 5v battery terminal to the orange pin labeled 5v. Solder a wire from the negative 5v battery terminal to any black spot labeled on the board.

BTW (JUST IN CASE): Check if there is continuity between the orange 5v spots I labeled. I just want to make sure you don't destroy your driver board.

 

[pmarcum]

Thanks for the detailed answer! I am planning on using either a RavPower Xtreme Series (26800mAh, output 5V/2.4Amax) or RavPower Element Series (10400mAh, output 5V/1.5Amax). Just a quick description of my project, in case you're interested: I am trying to make an inexpensive rearview camera for my husband when we are cycling ... he is virtually blind in one eye which impedes his ability to safely see around him on his left side, and his handlebar-mounted mirror is just not cutting it (it twists out of position, hard to view, etc). So I thought having a small display mounted on his handlebars connected to a little rearview camera that was mounted under his bike saddle aimed behind him would be a perfect way for him to safely view traffic (and me!) behind him! If this gadget works, I'll make another for myself and for my parents who are biking enthusiasts. I purchased a cheap little "rearview" camera (https://www.amazon.com/gp/product/B00X4EPFE0/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1) that supposedly already runs on 5V (I still need to verify this!). The plan is to power the camera and the display separately, and to connect them together with video cable (maybe even routed inside/through the bike's top frame tube). I think that either power pack should provide plenty of juice for a long bike ride ... do you agree? We getting ready to participate in a weekend-long charity ride (150 miles), so I am hoping that the battery pack can power the camera and display for at least 8 hours at a time before having to be re-charged. Thanks again for the wonderful details you've provided ... i can't wait to dig in and see if this crazy idea is going to work!

 

[TheGuy504]

Thanks for the detailed answer! I am planning on using either a RavPower Xtreme Series (26800mAh, output 5V/2.4Amax) or RavPower Element Series (10400mAh, output 5V/1.5Amax). Just a quick description of my project, in case you're interested: I am trying to make an inexpensive rearview camera for my husband when we are cycling ... he is virtually blind in one eye which impedes his ability to safely see around him on his left side, and his handlebar-mounted mirror is just not cutting it (it twists out of position, hard to view, etc). So I thought having a small display mounted on his handlebars connected to a little rearview camera that was mounted under his bike saddle aimed behind him would be a perfect way for him to safely view traffic (and me!) behind him! If this gadget works, I'll make another for myself and for my parents who are biking enthusiasts. I purchased a cheap little "rearview" camera (https://www.amazon.com/gp/product/B00X4EPFE0/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1) that supposedly already runs on 5V (I still need to verify this!). The plan is to power the camera and the display separately, and to connect them together with video cable (maybe even routed inside/through the bike's top frame tube). I think that either power pack should provide plenty of juice for a long bike ride ... do you agree? We getting ready to participate in a weekend-long charity ride (150 miles), so I am hoping that the battery pack can power the camera and display for at least 8 hours at a time before having to be re-charged. Thanks again for the wonderful details you've provided ... i can't wait to dig in and see if this crazy idea is going to work!

Awesome, I'm glad I can help you and your husband out. A 26800mAh hour battery would last
~75 hours. (Not including camera draw & if they aren’t lying about the mAh)

5v•26.8Ah= 134Wh
134Wh/1.625w= 82.5h
82.5 •.90= 74.2h

Good luck on the charity ride/ any other biking rendezvous to come!

 

[pmarcum]

Thanks again! Sounds like just one of those powerpacks will provide enough energy for both the camera and the display for our entire weekend of riding! One more quick question, if I may? Why wouldn't the red wire be soldered on the same pad where the XL1509 5V output leg was positioned? Maybe there is an advantage to putting the red wire on that bottom centrally-located "hole" (indicated in orange in your picture) rather than putting it in the upper right corner where the XL1509 5V output was located? One more question, driven completely from curiosity ... how the heck did you figure out that one of those "holes" in the central/lower portion of the board was an OK place to put a 5V input wire?!

 

[TheGuy504]

Thanks again! Sounds like just one of those powerpacks will provide enough energy for both the camera and the display for our entire weekend of riding! One more quick question, if I may? Why wouldn't the red wire be soldered on the same pad where the XL1509 5V output leg was positioned? Maybe there is an advantage to putting the red wire on that bottom centrally-located "hole" (indicated in orange in your picture) rather than putting it in the upper right corner where the XL1509 5V output was located? One more question, driven completely from curiosity ... how the heck did you figure out that one of those "holes" in the central/lower portion of the board was an OK place to put a 5V input wire?!

It's the same if you wire it to the output if the XL1509 or the hole, I just thought wiring it to the hole would be easier to do without shouting anything out. I found the 5v hole by poking around the board with my multimeter on continuity mode. If there is a connection between 2 points, it will make a beeping sound. If you don’t have a multimeter, I suggest you get one off of amazon for $10 because it is a good investment for electronic projects.

 

[pmarcum]

Ah, thanks for confirming that either location would work! I indeed have a multimeter (an old-school one ... it doesn't make any beeping sounds!) . I've confirmed that the resistance between the XL1509 5V output leg "pad" on the board and the hole that you have indicated to be 5V in that lower/central area of the board is zero (e.g., passed the continuity test). Weirdly, though, when I test for continuity between the lower right mini-connection on the pin where the red wire would be and the "pin #1" of the XL1509 (where there should be 12V input), I do NOT get continuity.

 

[TheGuy504]

Ah, thanks for confirming that either location would work! I indeed have a multimeter (an old-school one ... it doesn't make any beeping sounds!) . I've confirmed that the resistance between the XL1509 5V output leg "pad" on the board and the hole that you have indicated to be 5V in that lower/central area of the board is zero (e.g., passed the continuity test). Weirdly, though, when I test for continuity between the lower right mini-connection on the pin where the red wire would be and the "pin #1" of the XL1509 (where there should be 12V input), I do NOT get continuity.

I'm pretty sure that's because there is a capacitor that filters out voltage spikes on the 12v input of the board. I may be wrong though.

 

[Cradiak]

I'm a little confused, I have this screen on my GCP I'm working on, and I just took the 12V line on the wire that was next to ground and composite, and connected it to a 5v output from the GameCube mobo and it works fine. I didn't have to do anything special to get it to work, it automatically worked off 5v. Am I missing something?

EDIT: The reason I did this is since they are designed to work from 5-12V usually, I just assumed it would regulate the voltage appropriately.

 

[TheGuy504]

I'm a little confused, I have this screen on my GCP I'm working on, and I just took the 12V line on the wire that was next to ground and composite, and connected it to a 5v output from the GameCube mobo and it works fine. I didn't have to do anything special to get it to work, it automatically worked off 5v. Am I missing something?

EDIT: The reason I did this is since they are designed to work from 5-12V usually, I just assumed it would regulate the voltage appropriately.

Interesting... According to the datasheet of the onboard buck-voltage regulator (XL1509), it can take 5v in and output 5v. Whoops, looks like I overlooked that. I would still remove it since it could be wasting energy and reduce the battery life by a small amount.

 

[pmarcum]

Cradiak, my screen initially worked with 5 volts without having to rework the circuit, but then the screen started flickering, which I read somewhere is an indication that the screen isn't getting enough voltage. When I metered the output of my powerbank, I found that it was putting out slightly less than 5V (like 4.8V). I suspect that as soon as the voltage dropped below 5V, the screen stopped functioning correctly and instead flickered. I finally worked up the courage to do the rewiring, and by gosh the camera+screen are working as intended, powered by USB connectors plugged into a powerpack!