Hi all,
I am a first time user of this forum so I apologize in advance if this is the wrong place for this query.
I had a general question about the I2C pinout of both the Pixhawk 1.9 and Pixhawk 2.1 Cube boards/controllers. In the pinouts, the diagrams show that although the SDA and SCK lines run at 3.3 V using a pull-up resistor, the VCC pin supplies 5 V.
Why is there a difference between the voltage supplied to the peripheral and the voltage to run the SDA and SCK lines? How does the Pixhawk handle this? Does it use a voltage regulator?
Hi , in the MCU architecture the operating voltage is to 3.3V. The SDA and SCK are connected to the GPIO of the MCU. This is the standard voltage level also for UART and generally for the interfaces.
+5v Vcc is the voltage supplied to power devices connected to the i2c port. They are typically regulated down to 3.3v to supply the remote device’s electronics.
The levels are correctly stated as 3.3v logic levels.
Hi, I’m 5 years late to this discussion. I hope you are still an active member and can reply. In my case, the I2C boards are powered by 12volts and there are regulators to 3.3volts. I have always been puzzled how to attach the boards to arduino, but if I understand this correctly, I can just attach gnd, sda and scl and there is no worry about 12 volts coming into the processor? I managed to salvage a few hundred boards for measuring pH, electrical conductivity and temperature, but I have never tried to interface one because I was unsure what would happen with the 12 volt supply. GND from the supply and for the arduino will be common? Thanks!
