u/woganaga

This is my 6th PCB, but its the first 4 layer design I've done. Curious to hear any suggestions or feel free to drag my design.

Application: 11V input (3s Lipo Batteries) driving 4 WS2811B LED Strips drawing 3amp, 2 3v motors (drawing 1a total), IMP441 Microphone (off board), RS485 driver and Microcontroller.

What is it: This will be at the top of a 10 foot totem, the motors blow bubbles. Picture included for reference. I am a bit concerned about heat the board will be inside the device at the top of a 10 foot pole which will generally be in the sun, i was going to place the board on the bottom of the inside near one of the bubble fans to draw air over it and possibly put some reflective material over the top to reflect away heat.

Notes:

• Will end up using TPS565201s for the bucks. I tried to follow the layout on the datasheet as closely as possible. These two blocks are my biggest concern because i had to redo a previous design in the past for a boost converter because i didn't follow the datasheet as closely as i should have.
• I know i need to fix the orientation of some of the connectors...
• Followed the datasheet suggested layouts on all the IC's.
• Design decisions:
  • 3S LiPo / 11V source - the batteries will be at the bottom of the totem (10ft). I have 2s and 3s, went with the 3s for the higher voltage due to the length of the leads.
  • I use 1206 wherever possible due to it being immensely easier for me to assemble and its what I already have for most of the passives.
  • ESP32S-WROOM - I use these for all my projects, this will not be using the WiFi except for OTA programming.
  • To keep the part count down I am using the enable pin on on the motor block buck to turn on/off the motors. I didn't prototype/breadboard this piece out yet.

For my application I need to measure the level of a water tank precisely ( & cost effectively). For this application I need to sense the water level which can vary between 0-6 inches from a target. I started with the HC-SR04 Ultrasonic sensor and am still experimenting with this to improve the accuracy, but in the meantime I wanted to test out sensing the water level with a gauge pressure sensor.

I am using a XGZP6847A which measures 0-5kPA which should measure 20 inches of water. The device outputs .5 - 4.5 volts signal, and From my initial tests, the device measures the water level very accurately, even without adding circuits to filter any noise.

In my current setup, I simply have a voltage divider on the signal output to bring it into a 0-1v range for the microcontroller. The porthole on the pressure sensor is attached to a tube which then goes into the water to measure the pressure (see photos)

The issue I am facing is that over time (hours) the sensor drifts as if the water level is decreasing (it is not). I believe what is happening is that that over time air is making it into the tube somehow thus reducing the pressure. I used a ziptie and vaseline to seal the connection between the tube and the pressure sensor porthole.

My question is - what is happening here? Is this setup valid for measuring the depth, but the mechanism will always drift over time? Is the sensor defective? or am i not sealing the tube properly to the sensor (the tube is 3MM inner diameter which matches the porthole, its what i had on hand, but datasheet recommends a 2.5MM inner diameter tube. Before i spend more money on a narrower tube, I wanted to find out if this general approach will be accurate over time or if i should take a completely different approach, or if these economically priced pressure sensors are not the way to go (The devices i found on Digikey with similar specs to the device I'm using are in the $30 range, I was hoping to stay in the <$10 range). TIA I am stumped.

Datasheet for the sensor I am using (Purchased of ali) https://www.micros.com.pl/mediaserver/CZ_XGZP6847a010kpg_0001.pdf

I am lowkey jealous of all the super nice looking setups, so here’s my mess of a rats nest. Took a picture when I replaced my cable modem a few days ago

It’s pretty straightforward

- HP elite desk micro pc w/ 2 2tb usb drives running proxmox with 2 VMs and a bunch of containers

1 - homeassistant vm

2 - Ubuntu vm playground

3 - container w Prometheus, grafana and a bunch of exporters for my weather station, power monitoring,BitTorrent, aquarium data, etc. the Prometheus database mainly collects my aquarium, weather and power data.

4 - container running wireguard and BitTorrent

5 - Jellyfin server

The gaggle of circuit boards is my power monitor which measures the watts on all the electrical circuits

I have a little analog dashboard in my office which monitors server health.

Future plans - New server with gpu to handle Jellyfin and some inference projects, want to install an off cloud photo library and tail scale to access a few things remotely