Difference between push pull & open drain?

[chandu.kurapati]

Hi,

I was look up about the push pull and open drain configurations, i understand little bit about it. but in open drain configuration we can connect multiple devices but in push pull configuration we can n't connect the multiple devices.

why we can n't connect the multiple devices for push pull configuration? what is the reason for it?

Thanks & Regards,
Chandu.Kurapati.

 

[Audioguru]

An open drain is the drain of a Mosfet that has an external load. Then more than one Mosfet drain can be connected to a single load. If all Mosfets are turned off then one Mosfet can control the load.

A push-pull output has two transistors, one of them pushes low and the other one pulls high. If you connect two or more push-pull outputs together then if one output is low when an other output is high then they fight each other and might blow up.