Serial to TTL converter

Hey all! I am building a serial to ttl converter.I need someones help.

I made a circuit on pcb wizard, and checked it more then five times with the circuit i copied it from and i want someone to check it one more time for me if i missed anything please.

Here's a link to my picture:


The C8 capacitor may be wired backwards. I think the positive lead of the cap should wire to ground.

Here is a schematic of a SparkFun version of a RS-232/TTL converter that you can use to compair your circuit to.


Thanks! I am happy to see someone answering my post. I thought the community here dont help one another.

Your welcome. Most questions get answered in time one way or another. One can't always expect same day service for the price you pay. ;D


The schematic looked OK to me. You just re-entered the bit form the Serial Arduino in a different CAD package, right?

The C8 capacitor may be wired backwards.

There was some discussion of this in the course of the new Single Sided Serial Arduino designs a couple years back. It would be best to use a non-polarized cap here, since the voltages can go either way depending on whether the rs232 side is actually connected.