Hey guys,
I’m wiring up a set of three I2C devices to a single imp I2C output. I’ve got the addressing sorted out and everything, but power has become a problem.
I’m currently powering all three of these devices, as well as an accelerometer off the 3v3 output of the imp. The I2C devices each have 4 7-segment displays though, for a total of around 80 LEDs. This is obviously more than the 3v3 out can supply, so after I add a second I2C I get noticeable dimming. I haven’t tried powering all three simultaneously yet.
Question is, since these devices are actually designed for 5v anyway, could I just power them off the Vin and Gnd pins next to the power header (april board)? Will this have any negative consequences for the SCL and SDA logic pins? I currently have those pins bridged to 3v3 with 1 10k ohm resistor each. Will I be okay bridging them to 5vin?
Each I2C device already has a couple of 10k ohm resistors from VCC to SDA and SCL. I’ve also got a couple of capacitors on across 3v3 to Gnd for power smoothing, which I would plan to move over between Vin and Gnd.
Yay or nay? If nay, how would I go about splitting off 5v usb power for these devices.
Thanks guys!