New Person - Need Help Making Raspberry Pi Zero W Portable

Question

Hello everyone,

I'm very new to electronics and the Raspberry Pi space. I have a problem, and I just don't want to ruin anything.

I want to make my Raspberry Pi Zero W portable using a LiPo battery. I have gotten these links:

https://www.adafruit.com/product/2011

^^ The battery I would probably like to use. I would like for it to work for at least 2 hours, maybe more, if I can. I also need to conserve space because I am trying to make smart glasses.

https://www.adafruit.com/product/1304

https://www.adafruit.com/product/3196

^^This PCB to connect the LiPo Battery to the Pi Zero W

I am trying to make smart glasses where it takes input from a microphone (hopefully I can get a USB microphone and just connect it to the Raspberry Pi Zero W) and then takes the input, and sends it to my phone via Bluetooth, which then turns the audio to text. After that, it will take that text, send it back to the Raspberry Pi, and puts it up on the screen.

Question(s):

1) For the last link, I can't really find if it says that it will support Pi Zero W, it says it supports Pi Zero, does anyone know if it will also support Pi Zero W?

2) Will I need some other PCB to get to voltage to 5V or what I have it is alright?

3) I will also need to add a USB microphone and a small screen. Will this be able to handle it all / will I be able to connect everything onto the Raspberry Pi?

Thank you so much for looking at my question. I really appreciate it, and can't thank you enough.

fmilburn · Accepted Answer

Hi Fillip

I have not used the shim but the Pimoroni site gives a bit more information and in the comments several people report using it with the Zero W which draws less power than the Pi 3 which is also mentioned. https://shop.pimoroni.com/products/lipo-shim#show-review

The TPS61232 in the shim boosts to 5v so that is all you need.

Small OLED screens require very little power

There are also very low power mics but I’ve not used USB mics or checked their requirements

The 2000 mAH battery may not meet your 2 hour requirement - your average current cannot exceed 1 amp and your battery has to meet it’s full rating, be fully charged, and hold voltage down to the cutoff of the boost converter.
It looks like your choices will get you pretty close or exceed your requirements. Hopefully there is someone here who has actually used the hardware. Else you might also post on the Pimoroni forums.

Frank

hugohu · Answer

Oops. I don't have much experience with batteries. I'll go with Frank's answer for this one

feiticeir0 · Answer

Hi ! I know I'm late to this discussion, but, from my experience - I have a setup exactly like the one you want - a Raspberry PI Zero W (the W or without the W only means it has wifi integrated (with W) - but will consume more) . You will be fine with the first two links - The Adafruit Powerboost 1000C (the 500C will also work, but will take longer to charge the battery) and the Lipo Battery. You can check this project from adafruit. It has the same components you need and almos the same specifications: https://learn.adafruit.com/raspberry-pi-wearable-time-lapse-camera/overview your main problem probably will be to find a good ratio battery capacity/battery size for your glasses... Cheers

hugohu · Answer

Hi. The second link is only a charger. Lithium Polymer Batteries have a typical output voltage of 3.7V ***this information may be incorrect but the general idea is correct*** You'll need a booster to bring that up to 5V. https://www.adafruit.com/prod uct/2465 Perhaps? That's my go-to suggestion, since it comes with battery charging, USB 5V out, etc. The Pi0 and Pi0W are essentially the same thing. The only thing is that one has wifi, one does not, and some parts aren't in same place(but camera, SD, GPIO, power/data, hdmi) are all the same. 2 hours? I see here the pi 0 uses 120mA at idle and 170 watching 1080 HD video. With screen, I'd assume, perhaps, 130mA? An OLED would be suitable. (Monochrome, I mean) The battery indicated has 2000mA I'd suppose 300mA then an additional 50mA(this is pure guesswork) for bluetooth. it should, in theory work. You can also get 1A or so with that powerboost. let me know how the project goes.

colporteur · Answer

I will stage a test with a Pi Zero and a 4400maH battery. I just put the battery on charge for the evening and tomorrow I will dig through my Pi's to find a Zero I can test with. I typically use the latest Raspberry OS lite and configure enough to establish a ssh network connection. Do you have any other particulars you would not me to configure on the Zero? Once the battery is charged and the Pi is ready, I will write a script to log date and time to a file until the device dies. If you don't hear from me ping me for a response.

fmilburn · Answer

I think you are probably correct. I am just being cautious

colporteur · Answer

Current status Started Thu 14 Jan 00:14:17 CST 2021 battery at 2 of 4 charge points at Thu 14 Jan 18:50:01 CST 2021.

fmilburn · Answer

That is a good question. It appears Pimoroni does not give us a schematic for the SHIM which would be helpful but the header on the LiPo SHIM covers up SCL and SDA. I am not sure it is using I2C because the TPS61232 doesn't need it. In any event I2C can handle more than one device. SPI is not covered up which is good.

So when evaluating displays look for what pins are needed and realize the display cannot be directly placed onto the Pi. I assume you are placing the display away from the Pi so jumpers/wire is needed. If I2C is needed the pins will be covered up by the SHIM but you can solder wires between the display and the SHIM which is a bit of a hack. SPI would be less of a problem it would appear as the pins are not covered up so solder directly to the Pi pads. Look for displays that advertise they are useable with the Pi. If you are concerned about your choice, make a new post here on Element14. It sounds like an interesting project...

hugohu · Answer

I’m on mobile but I will check the pin outs. due to this I recommend the power boost. Its USB. Pj screen? Adafruit screens are pretty nice, might be a bit expensive. There are cheaper 3.5” screens via GPIO on Amazon with less documentation.

colporteur · Answer

Power supply failed (i.e. last entry in log) Fri 15 Jan 05:35:02 CST 2021 So to approximate 29 hours of runtime on the battery