AVR-Chat

The Micrel 5014 costs all of $2.05 (smt) or $2.48 (dip), qty 1, at Digi-Key.
It can be used high-side or low-side.   I have only used low-side to date,
figure 2 of the data sheet.   The only other component needed is the usual
bypass capacitor.    It doesn't get much cheaper or easier.

 

As for driving the 2804 directly with uC output, that depends upon the
voltages involved, ie, what supply you are using for the uC and what load
voltage you are switching.   You would have to be switching load voltages no
higher than the Atmel uC's supply voltage max of 5 V or so and that will
severely limit the ability of the 2804 to turn on fully (see the 2804 data
sheet).   Frankly, I would forget about trying to do this.   Just bite the
bullet, add the driver, and things will work beautifully, without any
problems.   

 

My applications are marine-related.  In the particular case of the 50 A
load, it is current for an MSD  ("marine sanitation device"), aka, sewage
treatment.  The current is continuous for 3-5 minutes.  Voltages are 12 VDC.

 

Steve

 

From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf
Of charlieknox
Sent: Tuesday, June 17, 2008 6:53 AM
To: AVR-Chat@yahoogroups.com
Subject: [AVR-Chat] Re: avr & power semiconductors

 

Steve - thank you for your info on these two. What are some 
applications you've used these in? I'm a newbie, just starting to 
learn, and I appreciate these hardware insights and experiences. 
Would you ever drive the 2804 directly from a uC output pin? If you 
can discuss the use of the driver a bit, that would be great. What 
do/would you say to the boss that says "we can't afford that extra 
part"? Thanks for any further insight you can add to your already 
helpful post. Info on things that work well for others, especially 
low power/drain components that "do the job" well, are always useful.

Thanks !!

Charlie






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