July 5th
Working in isolation
As not to blow up my Fraunchpad, C2000 Multi-DC/DC Colour LED Module, Three Phase BDLC Motor Driver or other independent module, I have ordered some Texas Instruments ISO7221 Dual Digital Isolators.
These are to similar to relays but are used but for low power and low voltage digital signals at much faster frequencies.
This allows my project's serial channels to be electrically isolated for protection. The last thing I want is some 50 odd volts from the BDLC motor driver or some introduced voltage potential difference to flow through where it shouldn't.
The ISO7221 is available in four different speed variations ranging from 1Mbps through to 150Mbps.
For this application I am using the 1Mbps A version. The deployment of ISO7221s is not dissimilar to that of placing buffers in your circuit except that you are deploying are also providing galvanic isolation.
Power doesn't come from vapour so the ISO7221 requires two sets of power. One for each side. Like buffers, there are specified voltage thresholds to be met for digital signalling.
