It's easier to use LT Spice to do a simple resistor string voltage divider analysis than to use a calculator! Much easier if you want to futz with values to hit some targets.
Copying the results from the DC analysis window requires highlighting and ctrl/c to get the text into the clipboard. There's no obvious "print" or "copy" or "save" things.
Interesting that Scad3.exe is only 5.4 megabytes.
John
There is: File -> Print, or save ... :-)
For writing to a bmp file you have to go to the Tools tab.
Mike Engelhardt sure knows how to program.
I once used a spreadsheet to print a table of the voltage divider ratios you get combining _two_ values of a resistor series and use it quite often. There has to be some utility around there to automate this for longer strings!
Pere
I have a PowerBasic program (called RUGRAT) that looks at all the resistors that we have in stock. I can specify if 0603/0805/1206 sizes should be included in any combination, then the target ratio and tolerance and range of Thevenin impedances. It then makes a report listing all pairs that fit, their error, and Thevenin impedance. This program has immensely improved my quality of life.
Some day maybe I'll include trimpots in various topologies, to help design trim networks.
John
I've been thinking of buying cheap coding to do javascript-based calculator for this. If anybody here would like to comment on most wanted features, I'll get it coded on rentacoder.com and will share the SW under BSD license.
Basic calculations
-Input ratio, find closest matches from E12-E96 series, with error
-Input ratio+output impedance, do the same
-Input resistance value, find closest series/parallel combination from E12-E96 series
-Input SMD code, output value
-Input value, output possible SMD codes
-Input any two of R1, R2, Rp, Rs -> output others
-Entry formats: 5120, 5k21, 0R1, 10M
-Calculations performed right when entered, no reloads or anything needed
Based on these:
-Input voltage, output resistor combinations for TL431/TLV431
-Input voltage, output reasonable resistor combinations for LM317
-Input frequency, output reasonable (how to define ?) resistors+caps for 555
Bonuses: Cut&paste available resistors into textbox. Values stored to cookie (or database, which would require serverside software..). Do the previous stuff with these values.
Forgot something ?
On a sunny day (Thu, 22 Apr 2010 17:14:54 +0300) it happened snipped-for-privacy@Mikko-Syrjalahtis-MacBook.local (Mikko
Trimpots ;-)
series
database, which would
Here's RUGRAT, my resistor ratio program. It only considers parts that we have in stock.
ftp://jjlarkin.lmi.net/Rugrat.jpg
Its output is a file, RUGRAT.TXT. I didn't do series/parallel combos, because that's not as serious a problem.
A voltage regulator calculator would be handy. It would have to cover a lot of different parts. Then it should include switchers... frequency, Ls, Cs....
I just use a cheat-sheet for Lm317/1117 type regs. Any time I need a new voltage, I add it to the sheet.
555? People still use them?The bummer about the standard E12-E96 values is that the same ratios keep appearing/not appearing. Throwing in a few of the oddball Susumu parts helps break that up.
John
E12-E96 series
database, which would
I like your rename for Internet Explorer. ROFL! Almost spilled my coffee ...
4 months ago I almost did for the first time in my life. Then I decided not to. I am sure it would have felt like a chef opening a package of Riceroni.Like a spectrogram where you never get anything between the usual lines?
E12-E96 series
database, which would
Stupid Windows won't allow me to hide the ugly icon. Or to change the icon to something more appropriate. Microsoft writes garbage.
I have to confess: I used a 555 once. Just once, honest. It ran off 12 volts and ran a charge pump diode thingie to make -5. Forgive me.
John
Actually, you can. Desktop Properties.
It can also be disabled. Ironically, I already disabled mine, and some time between June last year and now, it disappeared.
Tim
On a sunny day (Thu, 22 Apr 2010 12:27:06 -0500) it happened "Tim Williams" wrote in :
I just burned my xp disk
By which I mean, all settings relating to it disappeared. The icon is no longer available on Desktop Settings or TweakUI.
Turns out under Add/Remove Programs, Set Program Access and Defaults, IE was disabled. Now it shows up in TweakUI.
Tim
I just pooted...
On a sunny day (Thu, 22 Apr 2010 12:49:17 -0500) it happened "Tim Williams" wrote in :
xp users do all sorts of things it seems.
Is that Windows 7 ??
I certainly can hide it with Windows XP. ...Jim Thompson
-- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at
I wonder if '7' is the IQ of the ad agency that's doing the new commercials?
I'm getting concerned with all the horror stories I'm hearing about Windows 7.
My PC collection is getting aged (except for the laptop), so replacement is in the air :-( ...Jim Thompson
You can still upgrade your XP computers with new motherboards RAM and hard drives, but who knows how long before MS drops all support & updates?
They've got to get corporations (well, one anyway) to roll out '7' first. My computer at work was just replaced, with an XP box.
Would that be a loss ?:-) ...Jim Thompson
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