Luis Moreira wrote:

> I tried first to simulate the H-bridge but it came out with some funny
> results even with a resistive load...

Since there's not exactly "the" H-bridge, maybe you post your schematic?

> I got some funny results that I can not explain... current and voltage
> on the load are not as expected.
> Do you need to switch one of the transistors before the other?

You shouldn't have to, unless you're using a non-standard form to drive the
bridge. If the voltage and current at the load are not what you expect,
it's probably because one or both of your switching transistors is/are not
fully on. Check the voltage across C/E (or S/D for FETs) -- should be
minimal.

Gerhard
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