DC VOLATGE GROUND ISOLATOR SERIAL
DC VOLATGE GROUND ISOLATOR DRIVER
DC VOLATGE GROUND ISOLATOR SERIES

Bad dangerous idea, you'll fry your USB, don't do it at all.

Connect the battery's GND to the USB's GND, so both the arduino and the MPU are not so far apart in the ground path.

DC VOLATGE GROUND ISOLATOR DRIVER

Problem is, the driver uses the other ground, so it could stop understanding the arduino's control signals. Add a resistor between grounds so that the rise in one of them does not affect the other so much.I'm assuming a pull-up resistor on the MPU6050's board. Assuming Add the 330R resistors I mentioned earlier: they should make the '1' logic level signal more robust (because of the arduino's I2C pull-up.Add a big capacitor between the driver's +12V and GND terminals to supress pulses.You could: (in order from less work to more work) This is probably your problem: the inertial unit and the arduino see very different grounds when the motor produces a current pulse, and that's enough to make the logic mess up. The problem is when two components are attached to the ground path in different points, causing them to 'see' different grounds, and so they disagree on the logic levels. Voltage drops in the ground path happen in every circuit. The problem is that your motor is probably making a lot of current flow through this ground path, making some voltage drops appear on it. If the grounds are disconnected, the voltage the driver 'sees' will be random, since the driver's ground could be, say, 2V above the arduino's ground, completely messing up your logic. It does so by comparing the signal's voltage to its own reference (GND pin). Now, assuming you don't care about that, you just want the motor to not influence the rest of the circuit: the reason you need to connect the grounds is because when the arduino sends a 5V signal, the driver has to understand that it's a 5V signal. For all I know, it could go singularity when you show VDD+0.5V to its I2C pins)

DC VOLATGE GROUND ISOLATOR SERIES

You should use some kind of logic shifter or, at the very least, add a ~330 ohms resistor in series with the I2C bus to guarantee that when the arduino outputs 5V, the MPU6050's internal protection diodes survive (don't quote me on that though, the MPU6050's datasheet says nothing about this. Worst case, the arduino's 5V fries the MPU6050. Best case scenario, the MPU6050's 3.3V are not considered high by the arduino. So you were already living on the edge before adding the motor. You have no guarantees that it'll work with a 3.3V device.

Will adding a capacitor in series with the ground of arduino and motor driver solve this problem? If yes, of what value? Īnd here's a link to my motor driver specifications : Linkįirst, the arduino's I2C bus is 5V. If I separate the ground(motor driver i.e battery) from the arduino the motors do not respond, clearly they need a common ground to work in harmony. Clearly the battery is producing some sort of noise to the arduino, I'm using the lipo to power a motor driver (L298) which controls two motors. Here comes the big problem, the minute I connect a 12V lipo's ground to the arduino ground the MPU6050 stops responding.

DC VOLATGE GROUND ISOLATOR SERIAL

All works well now, I get raw values which is processed into angles and finally printed in the serial monitor. I have an MPU6050(gyro sensor which works on 3.3V) which is powered by the Arduino's 3.3V pin and SCA,SCL,INT pins are used with the I2C bus of the Arduino Uno which I believe is also 3.3V, and finally the ground is connected to the Arduino's ground. I'm have grounding problems (80% sure of it).

Dc volatge ground isolator