Requesting Feedback on PCB Design for ESP32-C3, Sensors, and SIM808 Module - Page 1
Forum section: electronics / projects

author: achraffff
author_rank: Newbie
timestamp: October 25, 2024, 09:42:15 pm
content: Hello everyone,I’ve been working on a PCB design for my project, and I would appreciate any feedback or recommendations you can offer. The design includes:1-ESP32-C3 for control and communication2-SIM808 module for GPS and GPRS with SIM card support3-MLX90614 for temperature measurement4-MPU-9250 accelerometer5-APDS-9960 proximity sensor6- Power management using TP4056 for LiPo battery charging and switching between external power and batteryI've attached the schematic and PCB layout below. I am particularly interested in feedback on:Power supply stability, especially for the SIM808, as I’ve included components for USB/battery power switching.Any suggestions to optimize power consumption (using ESP32 deep sleep, etc.).Ensuring proper communication via I2C between the ESP32-C3 and the sensors (pull-up resistor values, etc.).Antenna placement and routing for SIM808 (GSM and GPS antennas).Looking forward to your insights!Thanks in advance for your help.

author: tszaboo
author_rank: Super Contributor
timestamp: October 25, 2024, 10:44:19 pm
content: Where is your ground plane?

author: Salitronic
author_rank: Contributor
timestamp: October 26, 2024, 11:40:46 am
content: First off do yourself a favor and adopt some standard schematic drawing conventions with positive power rails always facing up and ground rails facing down, as it is, the schematic is a pain to read.I'm not sure if the ground plane is hidden or not present at all, but an RF design needs a ground plane. Even without RF you should have a ground plane always.The battery charger exposed pad should be connected to the ground plane for heat dissipation.As for the RF traces, you have it all wrong. You cannot route antenna feedlines just like any other trace. It should be short, avoid vias (unless you really know what you are doing), impedance matched, via shielded and with proper ground on both sides for a typical coplanar waveguide design.Apart from these very obvious issues, the quality of the images you posted does not permit further comments.

author: helloThere
author_rank: Contributor
timestamp: October 26, 2024, 11:48:38 am
content: Quote from: Salitronic on October 26, 2024, 11:40:46 amMost important comment on this thread.Schematic comments:For your 5V to 3.3V regulator, please put the symbol vertical. It's really hard to read when it's improperly oriented.Avoid 4 terminal connections and crossing over schematic traces when possible. It's really easy to have something connected improperly in both scenarios.I usually add a 100nF decoupling capacitor also to take care of the high frequency noise. Place the lower value capacitors closer to the component than the higher values.I usually have voltage nets pointing upwards and ground nets pointing downwards.You don't have any decoupling capacitors for the SIM808. My general rule of thumb is for every VCC add a decoupling capacitor (100nF). Keep this as close to the pin as possible on layout.Avoid overlapping text or symbols (see lipo connector).You don't need to create your symbols to follow the connector pinout--I usually place my VCC top and GND bottom. This allows me to orient the nets easier.No reset button on the ESP32?I personally would've kept all the ESP32 components directly connected on the schematic.Layout comments:I prefer 4 layers for prototype boards (signal, gnd, power, signal). My preference and it's pretty cheap usually.You can use polygon pours.A lot of people prefer not to use 90 degree angles.I'm sure you could get rid of a lot of your vias.I can't tell where the ESP32 chip is, but if you're using the SMD chip make sure the antenna is not on the board/near anything that could have interference issues.Some of your traces look strange--in the future I would suggest sending each layer. I can't really understand it as of now.Try and keep capacitor values (especially decoupling or clock capacitors) as close as possible to the pins.Just my 0.02. Take everything I say with a grain of salt.

author: PlainName
author_rank: Super Contributor
timestamp: October 26, 2024, 01:10:55 pm
content: QuoteBiggest hurdle is the schematic. Nothing is wired up, just labels all over the shop which one has to actually read to figure out what to look for, then go looking for every instance of that label (and probably miss one). There is no sense of flow, of what feeds into where or what drives whichever. It's like trying to read a map where there are just place names with no roads shown.I realise the way you've done it appears to be the rage if you've had a shufty online, but it is wrong. Do yourself, and anyone you want to figure out wtf this circuit is supposed to do, a favour and draw a proper schematic instead of what's effectively a table of parts.

author: floobydust
author_rank: Super Contributor
timestamp: October 28, 2024, 03:00:47 am
content: OP cross-posted like crazy, what an asshole:https://electronics.stackexchange.com/questions/728238/requesting-feedback-on-pcb-design-for-esp32-c3-sensors-and-sim808-modulehttps://electronics.stackexchange.com/questions/729107/pcb-design-feedback-request-esp32-sim808-and-sensor-integrationhttps://www.reddit.com/r/esp32/comments/1g60pos/requesting_feedback_on_pcb_design_for_esp32c3https://forum.arduino.cc/t/pcb-design-feedback-request-esp32-sim808-and-sensor-integration/1315789/7https://forum.arduino.cc/t/requesting-feedback-on-pcb-design-for-esp32-c3-sensors-and-sim808-module/1312445https://forum.arduino.cc/t/requesting-feedback-on-pcb-design/1315304https://forum.allaboutcircuits.com/threads/requesting-feedback-on-pcb-design-for-esp32-c3-sensors-and-sim808-module.203593edit: morehttps://bbs.esp32.com/viewtopic.php?t=40985https://discuss.tindie.com/t/pcb-design-feedback-request-esp32-sim808-and-sensor-integration/480070https://www.reddit.com/r/esp32/comments/1gdf6g4/pcb_design_feedback_request_esp32_sim808_andhttps://www.eevblog.com/forum/eda/pcb-design-feedback-request-esp32-sim808-and-sensor-integration

author: Simon
author_rank: Unknown
timestamp: October 29, 2024, 06:10:32 pm
content: Quote from: floobydust on October 28, 2024, 03:00:47 amAnd? what people do on other forums is not our concern.

author: PlainName
author_rank: Super Contributor
timestamp: October 29, 2024, 06:17:49 pm
content: QuoteIt's an indication of what they get up to, and they've just done it again here too.Wonder if it's an AI training thing.

author: Simon
author_rank: Unknown
timestamp: October 29, 2024, 06:28:35 pm
content: Not necessarily, people do do that, it's been brought up before and the answer was the same. We don't police other forums.

author: jpanhalt
author_rank: Super Contributor
timestamp: October 29, 2024, 06:30:20 pm
content: I believe the original post is a duplicate of another post on the forum..

author: Simon
author_rank: Unknown
timestamp: October 29, 2024, 06:36:47 pm
content: Quote from: jpanhalt on October 29, 2024, 06:30:20 pmYes, but when you get such a warm welcome from a long standing member you might try to start again with a new thread. I've seen it but I don't entirely blame the guy and here we are trashing his original thread.Tell you what, leave the moderating to the moderators! Think there is a problem? report it, don't start telling people off after stalking them on the net!

author: jpanhalt
author_rank: Super Contributor
timestamp: October 29, 2024, 06:51:43 pm
content: Quote from: Simon on October 29, 2024, 06:36:47 pmChill.It seemed to a casual reader (I have no interest in the topic) that you had misunderstood those objecting to the thread as duplicate. Sorry your seem to have been offended,

author: Simon
author_rank: Unknown
timestamp: October 29, 2024, 08:43:56 pm
content: This thread came before the duplicate. The OP was berated for having already posted on other forums. This is unacceptable! we have nothing to do with other forums. People have the option to not reply. It may well be a bot but with people deciding to o the moderation themselves it just makes it harder.

author: floobydust
author_rank: Super Contributor
timestamp: October 30, 2024, 07:53:22 pm
content: Try contribute sometime to a massively posted (on other sites) identical thread by a new account and you will quickly learn why they are awful and a waste of time to all involved. It's 10+ posts... is OP a bot or AI? Feel free to jump in for the lesson, do the design review and listen to crickets.I was going to help but searching for a part datasheet yielded all the multi-posts OP has. No need to stalk.For this project, there are different schematic, PCB versions and requirements posted depending on which website you visit. Lately it seems to have went from 2-layer to 4-layer and cross-posted again.So you have people pointing out issues on the previous rev, necro threads with OP not answering of any questions etc.This is when I get pissed off and get harsh. You're saying this is "moderation" by the community (me)?I could remain quiet, stick my head in the sand like an ostrich and deny OP (assuming not a bot or AI) the lesson that it's beyond bad Internet etiquette.How would you prefer I behave to someone entitled to all the help in the world? I'm not trying to piss you off as I have but vampires are destructive.

author: Simon
author_rank: Unknown
timestamp: October 30, 2024, 09:09:04 pm
content: If you don't want to help the guy then don't. Feel free to mention that he has posted it widely, but don't make it sound like he has broken any of our rules.