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Serial to Squarewave "AC"

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cbass

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This is probably a very odd question but yeah.

I'm trying to use a H-Bridge to switch the polarity given to two poles given a 0-5volt input.
The idea is to send serial data down a squarewave "ac" line by flipping the voltage and then on the other side using a diode to cut out the reverse flow leaving with pure data. And reconstituting the power voltage with a bridge rectifier.

The problem I'm having is that Logic Inverters do not give enough power output to drive the two transistors on one side of the H-Bridge. I've tried using another transistor to gain up the current, but that doesn't work.

To be honest, I'm not sure if this is even possible but it should be!
 
If you just want to transmit power AND data down a pair of wires there are much easier ways to do it. You can do it down a normal serial wire using a diode and large cap at the other end.

If you want more help you should state what voltage and current you need to transmit and what amount of data.
 
I understand that it's not the easiest way but this is the only way that you can viably send data to a microcontroller on a train on a trainset.
The reason for this is the polarity regularly changes. Also, a variable voltage would affect the speed of the train as the data is being sent.

Data is serial (any amount of data) but not very fast baud rate required.

Voltage is around 16 volts and the current is whatever a high current DC train requires. (I don't know, I'm trying to figure this out for a friend).
 
Well you could look up the few commercial standards that they already use for this type of thing.

But if you are set on doing a non-standard way I would still go for a DC solution with a constant DC and some very short pulses superimposed on the DC to act as the serial data.

You say there are "regular polarity changes" already? How does the train cope with that? And if something is already changing polarity, how will THAT thing cope with you changing polarty again?
 
The polarity changes are caused by the track.

Essentially all I'm looking for is a way to invert logic but with high current.
I've got a 0 volt rail that can go between 0v and 5v and I need the 0v to be converted into high current 5v (enough to switch fully on two transistors), these transistors will then control a FET which will sink 16v.
 
You need an H bridge chip. L298 is very popular, but it might not be enough, depending on what current your "high current" is.

Allegro makes a lot of high current H bridges.
 
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