H-BRIDGE schematics

Thread Starter

reviser

Joined Sep 25, 2013
6
I'm developing an h-bridge to control the speed and direction of rotation of a DC motor.
The motor I need to control is 24V 10A.
I've created a schematic for the the h-brigde but I'd like to hear some opinions about the overall schematic and/or the specific components I've selected.
Any suggestion is welcome.

 

Alec_t

Joined Sep 17, 2013
14,337
To upload your schematic file you need to click 'Go Advanced', then scroll down and click 'Manage attachments', then 'Browse' then 'Upload'.
 
The one he posted is correct and proper, depending on his choice of fets, this H-bridge can pull several kiloWatts.

I use almost that exact thing in my class d amplifier and bldc motor drive stuff.

All N-channel is the way to go, P-channel mosfets are a PITA to deal with, especially at higher bus voltages.
 

ronv

Joined Nov 12, 2008
3,770
The bootstrap caps seem pretty big, but having said that are you aware that it cannot run at 100% speed (always on).
 

Thread Starter

reviser

Joined Sep 25, 2013
6
My experience on the electronics field is a bit limited.
If anyone would like to suggest which components would be better instead of the ones I chose, it would be really appreciated.
 

ronv

Joined Nov 12, 2008
3,770
Take a look at the HIP4081 to replace your 2 IR2110's. Then you can still use all NFETs and it will run at full power..
 

SgtWookie

Joined Jul 17, 2007
22,230
Here is the image:

In the future, please upload your image to this Board. Use the "Go Advanced" button below the text box, then click the "Manage Attachments" button on the bottom of the next dialog.

.PNG-format images are actually the best to use here, as the image files are quite compact, are not "lossy" like .jpg are, and require no software other than a browser to view.

The 1k resistors R3 thru R6 will drain your boost caps far too quickly.

1N4007 diodes will recover far too slowly; you should use Schottky or switching diodes. 1N5818 or 1N5819 are likely Schottky candidates; 1N914/1N4148 might also be used.

You need to have the proper caps on both sides of the regulators and located as closely as possible to them. Without them, you will likely wind up with oscillators instead of regulators. See the datasheets. I suggest that you have at least a 100uF cap on your 24v input supply.

You will need to turn on the lower two MOSFETs in order to initially charge the boost caps; otherwise there won't be a ground path for the boost caps. As has already been mentioned, you won't be able to keep the high-side MOSFETs turned on for very long before the boost caps drain.
 
Last edited:
Top