On Sat, 11 Jan 2014 12:24:07 -0600, John Fields
wrote:

On Tue, 07 Jan 2014 20:07:41 -0800, John Larkin
wrote:

On Tue, 07 Jan 2014 20:01:22 -0700, Jim Thompson
wrote:

On Tue, 07 Jan 2014 18:57:28 -0800, John Larkin
wrote:

On Tue, 07 Jan 2014 19:55:02 -0700, Jim Thompson
wrote:

On Tue, 07 Jan 2014 18:53:05 -0800, John Larkin
wrote:

On Tue, 07 Jan 2014 14:06:14 -0700, Jim Thompson
wrote:

On Tue, 7 Jan 2014 14:55:39 -0600, "Tim Williams"
wrote:

Sure, if you like flappy gates.

Also, who would buy an inductor when three BJTs does as well?

I did the inductor thing years ago, must've been like 2008ish. Plus a
transformer:
http://seventransistorlabs.com/Image...off_Driver.png
But I'd much rather spend a few cents and as many watts with a CCS turnoff
than a few bucks inductor. Better still, just use H bridge drive (TL598).

Tim

I guess you didn't observe the load current?

In general I'd guess your attention span is limited :-} The need is
for a high side driver, controlled by a 3.3V logic signal.

And the inductor is ~7 cents in the quantities used by my customer,
and he's very cramped for space.

(In addition, schematic has been munged to hide details... customer
only has +3.8V high-side supply, which must deliver 8 Amps to load
with minimal drop.)

...Jim Thompson

How clever of you, to change the supply voltage to 12, to conceal from us that
the actual voltage is 3.8.

Well done!

Of course! I have to leave some tidbit for you to whine about.
Otherwise your sycophants will realize you're an idiot, and we can't
have that... at least not quite yet :-}

...Jim Thompson

So, how did you calculate the R and L values? I assume you did it twice, once
for 12 volts and once for 3.8.

Think about it JOHN! Fundamentals! Sheeeesh!

I'm sorry! I apologize! You're a victim of your Tulane kindergarten
education. My sincere apologies :-}

...Jim Thompson

OK, you can't do it.

---
Won't isn't the same as can't.

He won't because he can't.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation