Hi Jon

You might want to try the BTS555 from Infineon.  It is rated at 165 amps
with only a 1/2 volt drop.  The Ron is .0025 ohms so 40 amps will only drop
1/10 volt and dissipate 4 watts.  It is short circuit proof (520A),
temperature protected, overvoltage and ESD protected.  I think it costs
around $7.00.

Dave Mumert

----- Original Message -----
From: "Jon Jenkins" <jjenkins@STAFF.BOND.EDU.AU>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: August 15, 2003 4:22 AM
Subject: Re: [EE]: Switching large currents


> Hi Ling
>
> You are correct about the heat, at 40A the
> D1D40 will generate 90W no thats not a typo
> thats 90W!
>
> As this will be used for continuous periods
> that may be a little to much, I suppose I
> could include a heat feedback to switch
> it off if it gets to hot.
>
> Thanks for your assistance

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