This is probably an easy fix, but I can't find it for the life of me, probably because of all of my exams and hw. My latest project is a simple omnidirectional bot i designed, but when i power it the drivers do not turn on. I am using DRV8833 DC motor drivers with N20 motors. The microcontroller is an Esp32 DevKit1. My schematic is attached, and I previously had gotten a brownout when powering my circuit. I have the drivers connected to 3v3 and GND, and am currently powering it with USB, but I also have bad results with AA batteries. With USB, it flashes on for a second when I turn it on and off, and at first i thought the cap needed more time to charge and I had chosen the wrong uf value, but this is not the case. When powered with AA batteries, the drivers do not turn on at all. (Vin and GND pins). The problem is not the drivers, they turn on when powered with 3.3v. I do realize that 2 1.5V cells are not a lot of power, but it works for short durations. Any help would be welcome, thank you!
Sorry, the diagram makes no sense to me. Please post a hand drawn wiring diagram, with all pins, parts and connections clearly labeled.
As posted, that circuit won't do anything useful.
There are plenty of tutorials on line that describe how to wire up simple bots, so read through a few and pick one to follow.
I have looked through many, and I followed one. Could you tell me what the issue is?
The issue with your post is that the circuit diagram makes no sense at all.
What is it supposed to do?
I just want to power it, the actual inputs and outputs of the drivers are all wired also, but it should just be powering the drivers from the 3v3 pin. Sorry if this was unclear. The reason i posted this circuit specifically was because everything else on it works.
That is not a schematic.
You drew random lines. I doubt you designed a robot.
These are usually 6vdc or 12vdc.
You will never run two 6vdc or 12vdc motors with 3vdc.
NO.
Disconnect the drivers from the ESP32 3v3 and GND. Use external power for the drivers. Only use the ESP32 for signals (HIGH, LOW, PWM).
Learn to use the ESP32 to perform basic I/O... then try the car.
Or... internet search: ESP32 robot car ... follow one that you like.
Well, its a series cicuit.
1: Simply: if you are trying to run other devices from the ESP32's 3V3, DONT.
2: You cant use ohms law with a capacitor. You use Q = CV = IT
so a 25uF cap charged to 3v3 will provide 25ma for 3msec.
you will need seperate supplies; one for your motors and drivers, another for the ESP32.
Thank you, I didn't realize I should do this (regarding the 3v3 pin). I had tried following literal tutorials since I have never used ESP and always doen Arduino before, but I vehemently hate those L298N h-bridges that they all use. I don't mean to be rude with this last one, and you've been right for everything but obviously you can simplify to a series by just combining the loads, but as it is physically wired would it not be parallel if they are both being powered and the electrons can flow through either board?
your series circuit (CR and I dont understand what the purpose of either is in your application) is wired in parallel across the bridges and the 3V3.
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