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English => Interfaces, Pinouts, Cables => Errors and updates => Topic started by: Erik Christiansen on Feb 05, 2008, 09:53

Title: rs485_cable comments
Post by: Erik Christiansen on Feb 05, 2008, 09:53
In the RS232 to RS485 interface converter circuit, the series combination of R9 and R12 is in parallel with the 120 ohm R3, for termination purposes. (Return through C1,C2,C3,C4) The result is a termination under 86 ohms. R13 = 200 ohms would result in a 120 ohm termination, I believe.

Erik