Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: Ro-Bot-X on April 24, 2010, 06:46:07 AM

Title: Choosing a SMD H-Bridge
Post by: Ro-Bot-X on April 24, 2010, 06:46:07 AM

I need some help choosing a SMD H-Bridge IC. I have always used the SN754410, but now I want to make a tiny robot and I need something equivalent. The bot will be powered by a 3.7V LiPo, the motors are pager motors and the logic voltage will be 3.3V. Anything really cheap that I can find at Mouser would be perfect. I have browsed through tons of ICs but can't quite find a proper one.

Thank you in advance.

Title: Re: Choosing a SMD H-Bridge
Post by: Ro-Bot-X on April 25, 2010, 05:18:33 PM

No ideas? Anyone?

Title: Re: Choosing a SMD H-Bridge
Post by: Soeren on April 25, 2010, 05:35:30 PM

Hi,

How much do these pager motors draw tops?

One option would be to pour a handfull of SMD transistors on a tiny PCB, but until such time as you reveal the data needed, it's hard to say what would be the best solution.

You ought to know that we need data like:
How much current?
How tiny? (no adjectives, just metrics please ;))
How cheap?

Title: Re: Choosing a SMD H-Bridge
Post by: Ro-Bot-X on April 25, 2010, 07:14:54 PM

Sorry about the lack of data. I guess I need up to 500mA per motor (pager motors draw about 280mA at 3.7 V). About the size, anything that is SMD and can still be soldered by hand. Sorry I am not familiar with all the SMD capsules and sizes. If I knew, I wouldn't have to ask for advice.

I thought people would chip in and say, look I am using this thing for low power motors, perhaps you can use it too.

Thanks for any advice.

Title: Re: Choosing a SMD H-Bridge
Post by: Webbot on April 25, 2010, 07:24:10 PM

The only one that springs to my mind is the Sanyo LB1836M used in the original BabyOrangutan boards.

Title: Re: Choosing a SMD H-Bridge
Post by: Ro-Bot-X on April 25, 2010, 09:12:21 PM

Thanks, that might be perfect!

Title: Re: Choosing a SMD H-Bridge
Post by: Soeren on April 25, 2010, 09:59:12 PM

Hi,

Yes, it seems fine: Datasheet here (http://www.pololu.com/file/0J25/LB1836M.pdf)
It has got 1 mm pitch, so should be solderable with a steady hand and lots of light and perhaps a magnifier, but I don't know if $3.49 is cheap enough?

Title: Re: Choosing a SMD H-Bridge
Post by: Ro-Bot-X on April 26, 2010, 05:37:16 AM

Well, I intend to build a swarm of robots, so anything cheaper that fits the profile is welcomed. Especially if I can get it at Mauser, so I pay for only one shipment for all electronics, that would be great!

Thank you!