Please help me finalize my DS Lite AIO (with dual screens)

Got an idea for a project? Found a cool project you want to share? Post it here!
Post Reply
User avatar
Sushi
Posts: 98
Joined: Sat Jul 23, 2016 8:17 am
Location: East USA
Has thanked: 4 times
Been thanked: 34 times

Please help me finalize my DS Lite AIO (with dual screens)

Post by Sushi » Sat Jul 14, 2018 6:30 pm

ICs:
-TPS60190RSAR - Boost converter
-MCP73871 - LiPo charger
-ATMEGA32U4 x 2 - Arduino compatible microcontroller
-LM3671MF (5V --> 3V3) - LDO regulator
-PCM2704C - USB sound card
-MAX98306 - Stereo audio amp
-FE1.1s - USB hub
-TXB0108 - Level shifter

TODO:
-Add voltage divider to battery so arduino can measure voltage

I've got a PCB that's close to ready to be fab'd, but I want to be sure it'll be functional before I do that.

How it works:
TPS61090 boosts LiPo voltage to 5.2 volts for the entire system. Works alongside MCP73871 which charges battery. This is the powerboost portion. I have two ATMEGAs because I need both USB functionality and a lot of pins. One is almost entirely dedicated to the lower display while the other handles buttons. They communicate over I2C. The LM3671 takes 5V and converts it to 3.3 for the level shifter. The bottom display's logic runs at 3.3 volts, so it needs to be connected to the 5 volt arduino through the TXB0108 level shifter. The PCM2704C is a full USB DAC and the MAX98306 is a 3.7 watt stereo amp. The FE1.1s is the USB hub connecting the arduinos, sound card and an external USB port.

I've got a full BOM but still need a physical way to control volume. I was thinking about hooking the PCM2704C into one of the arduinos and having it be controlled on screen, but then there's an unused bit on the DS case.

This is my first complex board, so I'm sure I've made a mistake somewhere. I'd appreciate any feedback, especially if you've used these chips before. The schematic is attached to this post. Once it's done, I'll release the board files.

P.S - I've taken some schematics directly from Adafruit. I know the designs work and I've been using them on breadboards for testing.
Image of the unfinished UI for the touchscreenShow
foto_no_exif.jpg
foto_no_exif.jpg (2.47 MiB) Viewed 1304 times
Upper left black button is screen calibration
Upper left big red button brings up shutdown dialog (shutdown system, screen or arduino)
Upper left gray blobs are indicator for caps, shift, ctrl and alt
Lower left bar is battery meter
Buttons below left and right click are for holding left or right
Arduino will auto shutdown everything if voltage is too low
Attachments
DSLAIOV2.zip
(177.96 KiB) Downloaded 69 times
Last edited by Sushi on Fri Jul 27, 2018 12:01 pm, edited 1 time in total.

User avatar
Tinkerman92
Posts: 17
Joined: Thu Jun 07, 2018 3:53 pm
Location: United States
Has thanked: 4 times
Been thanked: 1 time

Re: Please help me finalize my DS Lite AIO (with dual screens)

Post by Tinkerman92 » Fri Jul 20, 2018 10:57 am

Why do you need a voltage divider for the battery monitor? Arduino can handle 0-5v on analog pins. To measure voltage you have to hookup before the step up converter.

Also do you mind putting a description in the OP next to the ic list, ex. Ic977 - op amp

User avatar
Sushi
Posts: 98
Joined: Sat Jul 23, 2016 8:17 am
Location: East USA
Has thanked: 4 times
Been thanked: 34 times

Re: Please help me finalize my DS Lite AIO (with dual screens)

Post by Sushi » Fri Jul 27, 2018 12:04 pm

I don't need a voltage divider. I'm not sure why I thought I did. I've not touched this for a while, but I'm reconsidering having all the circuits implemented on the board. It would be much easier to design a "hub" to which separately purchasable boards can be soldered. It saves soldering effort and is actually cheaper for one-off boards.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest