Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Difference between push pull & open drain?

Status
Not open for further replies.

chandu.kurapati

Full Member level 3
Joined
Oct 31, 2013
Messages
186
Helped
5
Reputation
10
Reaction score
5
Trophy points
1,298
Location
Bengaluru, India
Activity points
2,778
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

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,284
Helped
2,141
Reputation
4,276
Reaction score
1,968
Trophy points
1,393
Location
Toronto area of Canada
Activity points
58,419
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.
 
Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top