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Electronics => Electronics => Topic started by: Hawaii00000 on June 16, 2009, 10:47:56 PM

Title: Transistor + relay...Does it exist?
Post by: Hawaii00000 on June 16, 2009, 10:47:56 PM

Hey guys and gals,
Does anyone know if there's a relay I can buy that has  a transistor built into it? I need to build a h-bridge and the less pieces I have to mess with, the better.

Title: Re: Transistor + relay...Does it exist?
Post by: SmAsH on June 17, 2009, 12:38:03 AM

why not just DIY it?

Title: Re: Transistor + relay...Does it exist?
Post by: Asellith on June 17, 2009, 06:30:15 AM

use a solid state relay. Thats kinda what they are. If you get the right one it could run off lot level logic. Need to shop around.

Title: Re: Transistor + relay...Does it exist?
Post by: Hawaii00000 on June 17, 2009, 05:54:21 PM

I did bit of research after this post and I found some h-bridge ICs. Would that work with a 12 volt battery? If not the solid state relay should work.

Title: Re: Transistor + relay...Does it exist?
Post by: Soeren on June 17, 2009, 06:30:47 PM

Hi,

Hard to say when when you keep the type number a secret ;D

Title: Re: Transistor + relay...Does it exist?
Post by: Hawaii00000 on June 17, 2009, 08:10:35 PM

Do you mean the type number for the IC? Someone suggested a ISL2110 or ISL2111 from Intersil ( http://answers.yahoo.com/question/index?qid=20090416074917AASbNVx (http://answers.yahoo.com/question/index?qid=20090416074917AASbNVx) )... would that work?


I'm not exactly  sure of the motors and battery but I will be using two motors rated for 12v.

Title: Re: Transistor + relay...Does it exist?
Post by: HDL_CinC_Dragon on June 17, 2009, 09:56:14 PM

We need to know the current too. How much current does your motor draw under load?

Title: Re: Transistor + relay...Does it exist?
Post by: Hawaii00000 on June 17, 2009, 10:20:45 PM

Honestly, I'm not completely sure. One motor I am looking at says "Horse Power Cont.— 60mA" (with no load) so I guess that means it draws 60mA.
Is that right?

Title: Re: Transistor + relay...Does it exist?
Post by: SmAsH on June 18, 2009, 06:34:44 AM

"no load" means its spinning freely. look for something that says "stall current" and that is the MAX current your motor will draw.

Title: Re: Transistor + relay...Does it exist?
Post by: Hawaii00000 on June 18, 2009, 04:42:42 PM

I can't find any other current rating besides that one, and I think I might have to put this post on hold for a day or two, because I'm getting kinda confused with motor specs. I thought I found a good motor for the job, but now I'm not so sure.  ???

Title: Re: Transistor + relay...Does it exist?
Post by: lemontree on June 19, 2009, 12:48:13 AM

If you must use a relay then maybe look up some information on reed relays. I still think they are kinda cute:
http://en.wikipedia.org/wiki/Reed_relay (http://en.wikipedia.org/wiki/Reed_relay)

Title: Re: Transistor + relay...Does it exist?
Post by: Hawaii00000 on June 23, 2009, 01:57:34 AM

Ok so the I think I'm gonna use a motor that runs on 9v and has a stall torque of 17A.

Title: Re: Transistor + relay...Does it exist?
Post by: Trumpkin on June 23, 2009, 07:14:32 AM

Quote

If you must use a relay then maybe look up some information on reed relays. I still think they are kinda cute:
http://en.wikipedia.org/wiki/Reed_relay (http://en.wikipedia.org/wiki/Reed_relay)

A bit more complicated (and more pieces) then a normal relay, eh?