Intro: Smartphone Powered Laptop
E-waste is becoming an ever increasing problem in our disposable society. In order to promote the idea of a circular economy I have revived a broken laptop (2007 17" Macbook Pro) by powering it off my smartphone. The idea behind this is as smartphones become increasingly capable and ubiquitous, this project can serve as an alternative to binning your old laptop.
In this instructable I used an Android phone (Google Pixel 2), however I also have included instructions (untested) for iOS users as well. I also understand that not everybody will be able to source the same laptop as me but general concepts should still apply. I would also recommend a certain degree of DIY electronics experience as well as equipment (soldering tools, dremel, voltmeter, screwdriver set... etc).
As with all DIY projects nothing ever goes exactly as planned, do your research, be patient and stay positive!
Step 1: Sourcing a Laptop
I sourced my 2007 17" Macbook Pro from the Edinburgh Remakery (image 1). They collect old/broken electronics among other things, and refurbishes them, recycles them or breaks them down for parts.
Attached is a teardown video of said laptop.
Step 2: Powering the LCD
After gutting out the motherboard, battery, fans, optical drive, hard drive, speakers and everything else. You should be left with just the chassis and the screen.
The first thing to do is find out the LCD panel model number, you can usually find this on a sticker at the back of the panel. Mine is [LP171WP4(TL)(B1)]. From there find the LCD controller needed to power the panel. For mine it's [M.NT68676.2A] (image 1) which I got off Amazon. There should be two inputs on the LCD panel, one is the included FIX-S6 30Pin LVDS cable (if your LCD controller doesn't come with one be careful there are different variations). This goes straight from the LCD controller to the panel. The other is for the backlight. This goes from the LCD controller, through a backlight inverter (included) to the panel.
My LCD controller didn't come with a power supply so I sourced a used one from my Uni.
Image 2 shows me testing the panel on a PC.
Step 3: Mirroring Phone Display
The next step is to mirror the LCD's display to that of your phone. It is best to use a recent flagship phone for an optimal performance, although this doesn't matter that much.
Next you will need a Displaylink adapter (image 1) to interface between USB and HDMI. I got mine here, and to interface between USB-A and USB-C I simply used the adapter included with my phone (image 2). This should be pretty easy to source even if your phone doesn't come with one. Please refer to (image 3-4) for exactly how it is setup. Attached is a video of me testing this setup.
If your phone supports USB alternative modes like DisplayPort Alternate Mode (such as Samsung Galaxy S9 or LG V30), you can skip this step entirely and simply go for one of these.
For iOS users you will need a Lightning to HDMI adapter. You can get one here.
Step 4: Keyboard
Becasue Displaylink uses USB the keyboard will have to be connected via bluetooth. To do this I first removed the keyboard and the metal tray supporting it (image 1-3). This proved to be quite difficult as the keyboard was riveted on.
Next I acquired an unused bluetooth keyboard from a friend (image 4). You can also find one on Amazon for next to nothing. However, due to the height of the keyboard I had to remove the case and re-house the batteries in a PVC tube (image 5-8). Lastly, I hot glued the keyboard onto the panel (image 9). You will thank yourself for using hot glue later on come the time you try to make everything fit inside, and realize that you need to reposition something.
For those with USB alternative modes phones, you can use a wired keyboard using the aforementioned adapter.
Step 5: Phone (Trackpad)
For the phone (trackpad) I ripped out the existing trackpad and enlarged the opening with a dremel (image 1). I made the height of the opening match the width of my phone, while the length of the opening was 2 cm taller than my phone to make it easier to plug in and plug out.
For the cradle in which my phone will sit I 3D printed a simple tray with an opening on one side for the USB-C adapter (image 2-3). However, I found some of the aluminium reinforcement under the panel interfering with the tray siting flush with the opening. So I gingerly chipped away at it with a dremel (image 4). Then I hot glued the cradle onto the panel (image 5).
If you do not have access to a 3D printer, you can also use the plastic tray that comes with most phones out of the box.
Step 6: On/Off Button
For the on/off button I decided to do away with the bulky PCB which came with the LCD controller (image 1), so after configuring the display settings to my liking and turning the volume all the way up (you can still control the volume later on from the source i.e. the phone). Instead, I integrated the on/off into the existing on/off button next to the keyboard (image 2).
To do this simply requires shorting two pins. Using trial and error I quickly deduced which two pins needed to be shorted in order to turn the display on and off. From there I re-purposed the existing connector for the two wires soldered onto the button (image 3).
Attached is a video of it working.
Step 7: Speakers
For the speakers I simply used the ones that came with the laptop. To interface with the LCD controller I soldered them up to a 4-pin connector (image 1-2).
After a number of test fittings I found it best to glue the speakers to the panel (image 3) rather than the chassis, this however doesn't apply to all laptops so please remember to keep testing how things fit together at every stage of the build, you'll thank yourself later for that.
Step 8: Assembly
Now comes the tricky part of getting everything to fit together. My original plan was to fit everything inside the body of the laptop. However due to the laptop being too thin and the LVDS cable being too short, I had to stick the LCD controller on the back of the lid. (I was under time constraints so I couldn't just order a longer cable, you probably won't have this problem so feel free to try fitting it inside)
First I dremeled a hole out of the air vents (image 1) to allow the HDMI and backlight inverter cable to pass out of the laptop. With that I popped the Displaylink adapter and backlight inverter inside the body and routed the smaller cables/wires through the hinge instead. I then stuck the LCD controller on the back with two-part epoxy (image 2), as the tension in the HDMI cable was too strong for hot glue.
I also wrapped the backlight inverter in an anti-static sheet (image 3). This is because of the high voltages involved with the backlight inverter (image 4).
Image 5 shows what it looked like inside before I closed the lid. However, keep in mind that your laptop may be different, this will affect how you assemble and layout your components.
Step 9: Optional Additions
Here are some optional additions I made:
1. I lengthened the power cable by 1 meter (image 1-2), it makes it a bit more usable.
2. I lined the inside of the phone cradle with cloth padded with velour underneath (image 3) to hide the 3D printed plastic.
3. I moved the power input from the back to the side by making a cable consisting of a male power plug on one end (image 4), and a female power plug on the other (image 5) which I glued into the hole of the old power port (RIP MagSafe).
Step 10: Software
When it comes to software first you need the DisplayLink Presenter app in order to mirror your display via the Displaylink adapter. (iOS users and phones with USB alternative modes using the aforementioned adapters don't need this) Secondly, you'll need a desktop based launcher. There are a few floating around the Play Store, but the best one in my opinion is Sentio Desktop (image 1). I also got the accompanying File Explorer for a more desktop-like experience.
The problem with simply mirroring your phone's display is that the phone lacks a mouse cursor. As a result, the 'trackpad' is awkward to use, requiring you to look where you tap/press. The solution is the app Tap Pointer (see attached video), the catch is that it requires you to root your phone. Please do this at your own risk. Alternatively, you could use a Bluetooth mouse.
If you're after a truly desktop experience you can run Windows or Linux from an emulator. I've found most success with Bochs but you can also try Limbo. In image 2 you can see Windows XP running on my phone. Alternatively, you can use TeamViewer or Microsoft Remote Desktop to stream/control your computer remotely. This does however require a good internet connection.
For iOS users you will need SBRotator to re-orientate your desktop into landscape. This though requires you to jailbreak your phone, so do this at your own risk.
Step 11: Result
Here are the results.
Thank you for your time and good luck!