I have a home-brew "video processing" board that has ±15V and +5V supplies, the ±15V for the analog and the +5V for the logic.
And use the two diode/two resistor gimmick to get sliced analog into the digital stream.
...Jim Thompson
I have a home-brew "video processing" board that has ±15V and +5V supplies, the ±15V for the analog and the +5V for the logic.
And use the two diode/two resistor gimmick to get sliced analog into the digital stream.
...Jim Thompson
-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
What I want is an LM317 in SOT-23. Haven't found it yet, and thousands of ldo's don't help.
John
Oh, quit whining. ;-)
Less of a whine, more of a rumble, but here's a sign of more money than sense..
Best regards, Spehro Pefhany
-- "it\'s the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
Hello John,
Sometimes the old discrete solution remains the best. I find that many times in my designs. Lots of 3904, BAV99 and stuff like that. Can't really beat the prices, with 0402 resistors costing under 1/2c.
-- Regards, Joerg http://www.analogconsultants.com
Hello Frank,
The 80% doesn't matter because much of the stuff will go dormant after shutting down. What matters is the cumulative current draw of all systems. However, it still needs some juice to keep things like a realtime clock going. A microamp or so. When the circuit wakes up then all kinds of other electrical gear will be going. Fans, A/C, lights, radio etc.
The chip is more geared towards automotive but with a zener you can get it into the right range. There isn't much choice for 24V systems, you've got to make do with what's there, or design a discrete circuit which is what I often decide to do.
-- Regards, Joerg http://www.analogconsultants.com
That's expensive.
Best regards, Spehro Pefhany
-- "it\'s the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
Hello Jim,
Yaaaaawn...
Now I remember why I quit subscribing to paper issues of such magazines a long time ago.
-- Regards, Joerg http://www.analogconsultants.com
Hello Jim,
With a BSS123? About 4-5 cents.
-- Regards, Joerg http://www.analogconsultants.com
spendthrift! I'd use an 8050 and three resistors. Well under a penny, and output close enough to zero/Vcc for practical purposes.
Best regards, Spehro Pefhany
-- "it\'s the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
What, and go Off Topic?
Now that is bizarre. Why not just put a stick of dynamite in it?
John
In order to get the cheap magazine mailing rate, USPS regs require a certain amount of "editorial content", but the regs don't address the quality of same. And all the people who work for the mags are journalism majors.
John
Get rid of the comparator. Poke the signal directly into the base of a cheap NPN transistor, and pull up the collector.
John
John, You're becoming a hacker ;-)
...Jim Thompson
-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
No, it's just easy for beginners to confuse hacking with elegance.
John
Really ?:-) A NPN detects ZERO crossings?? And you left out a base resistor in your hack ;-)
...Jim Thompson
-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
Well, you never defined zero, and I'd use a resistor if it needed one.
Now, this vanilla cream blueberry brioche is elegant. I knew there had to be a reason to locate an electronics company in a place like this.
How about this...
+------+------ v+ | | | r | | r +------out | | | c in------ka---+-----b e | gndJohn
Hello John,
Sad. That would mean that some magazines might slowly degenerate to mere ad pamphlets.
-- Regards, Joerg http://www.analogconsultants.com
Hello Spehro,
Well, Jim capitalized "zero" so I figured he'd want it to within 10mV or so :-)
Then there'd be the inverted transistor rectifier, might get it close enough as well. Another option could be to run a comparator between 0V and 5V and fudge its input common mode range. Might need a dual BAT54 though and that would add around 2c :-(
-- Regards, Joerg http://www.analogconsultants.com
Nothing to limit base current ?:-)
Not to mention that it doesn't even zero-cross detect ;-)
...Jim Thompson
-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
You refer to Electronics Design Magazine, I assume,
"The Authority on Emerging Technologies for Design Solutions"
which deconstructs to
"You're Too Dumb to Design it Yourself so Buy the Stuff We Advertise."
Their articles always start with a journalism-ese hooker line like "Current measurements are used in a variety of equipment for control or safety functions" and similar pearls of wisdom. My rule is to never read the first paragraph at all.
John
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