I created a schematic for the MAX3485 with the ESP32, but I have a question about the selection of biasing resistor(R39,R40) values. Some people use 4.7k, 10k, and 20k ohm resistors, but I'm unsure what the exact value should be and how much current is required. Does anyone have insights or suggesti…

Selecting biasing resistor values for MAX3485

jim-p August 19, 2025, 4:04pm 13

That is quite true!

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