hello guys...
in the LMD18200T(http://pdf1.alldatasheet.com/datashe.../datasheet.pdf) there is one input for the direction of the rotation....so if I choose not to use the PWM and Brake options..( they show in the datasheet how to cancel them ) would be the single direction input enough to drive the h-bridge inside the IC ?? and ...another thing i dont understand... the current sensing pin .. what is it for ??

 

ANS #1) Yes, tie PWM high and Brake low and you can operate Bridge with just the direction input. See the truth table on Page 6 of datasheet

ANS #2) The current sense output is for measuring current flowing through the bridge. Datasheet says 377uA/A so if the bridge is sourcing & sinking 2A then this output will source 754uA. This is useful if you want to put an upper limit on how much current can be sourced (think fault conditions). I imagine you can run this output into a scaling resistor to ground to convert it to a voltage output. Then some comparator circuit can set a threshold to shut down the drive if a fault condition lasts for too long. It is a protection feature.. if you dont want to use it, leave that pin open-circuit. But providing fault protection for your bridge is a good idea. Ignore at your own risk.

 

aha i see....thanks for the reply...
i am not using the IC in any circuit.. i was just searching for h-bridges ICs and i found they are all the same like the LMD18200 with these features.. i just wanted to know more about it ...
thank you a lot..