Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: royalbird.raman on August 28, 2010, 12:47:44 AM

Title: doubt about H-bridge..
Post by: royalbird.raman on August 28, 2010, 12:47:44 AM
sir,
I am an ICE student 1st year Delhi University.I am new to robots.srry not even new, i started studying microcontrollers on my own.

I have a doubt in H-bridge whose link is given below.If A=0,B=1 ,then the some current should enter B->A->gnd. Now if the answer is diode,then wouldn't this diode stop the current entering A when A=1,B=0.
srry if i asked a stupid question..I u can help,I will be thankful to u.

http://www.societyofrobots.com/schematics_h-bridgedes.shtml. (http://www.societyofrobots.com/schematics_h-bridgedes.shtml.)        ----->link of H-Bridge diagram.
Title: Re: doubt about H-bridge..
Post by: Admin on August 28, 2010, 08:21:08 PM
Quote
I have a doubt in H-bridge whose link is given below.If A=0,B=1 ,then the some current should enter B->A->gnd
Current will not pass through a MOSFET when the gait is turned off. So if A=0, no current will pass through it :P
Title: Re: doubt about H-bridge..
Post by: Soeren on August 29, 2010, 06:27:36 PM
Hi,

It seems that it's drawn with N-ch devices only.
(Always use P-ch devices at the top, or you'll need a higher voltage than the motor voltage to drive them).
Title: Re: doubt about H-bridge..
Post by: macdad- on August 30, 2010, 05:13:16 PM
Hi,

It seems that it's drawn with N-ch devices only.
(Always use P-ch devices at the top, or you'll need a higher voltage than the motor voltage to drive them).

To second that, follow the rule of "Collector to load" always have the collector facing to the load(or drain if using mosfets)
Title: Re: doubt about H-bridge..
Post by: Admin on August 31, 2010, 04:21:28 PM
It seems that it's drawn with N-ch devices only.
(Always use P-ch devices at the top, or you'll need a higher voltage than the motor voltage to drive them).

agreed . . . i saw that mistake like 4 years ago and still haven't fixed it . . . maybe I should do that now . . . lol