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Your load resistor is 100 Ohms. C12, in series with the 100 ohms wants to have an Xc of a lot less than 100 ohms (less than 10 ohms is good) at the baud that you will be using. Many similar circuits replace the capacitor with a short-circuit. The purpose of the capacitor is to reduce power consumption when there is no data flowing. If it were me, I would use a 10uF (because I have a lot of them in my parts bin!)although many different values would probably work well.

Thanks! I'll try a 10uF then, using 100nF now.. There must be something else wrong with the whole circuit (this image is just a piece of it) RXD and TXD connects to a PCA82C250 and then to CAN bus, it communicates but seems to lose data...

Try replacing c12 with a short circuit temporarily to see if that helps clear up the lost data problem.


Uploaded the whole schematic


Tried with shorted C12,C13 , tried without short, same result (100nF) - Also didn't use C8-C11

Got an CAN error on selfcheck but when i switched U3 & U5 it was gone.. :/

It dosen't seems like a complicated circuit to duplicate but I have no luck...