Random comments on common errors in technical documents
 User Name Stay logged in? Password
 Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read Search

 The Lounge A place to talk about almost anything but politics and religion.

 Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
 3rd July 2012, 06:36 PM #91 DF96   diyAudio Member   Join Date: May 2007 No contradiction at all. Linearity does not necessarily imply large output, and it does not necessarily require simple proportionality as a constant bias can be involved too. All linearity, in the context of a PSU, means is that if raising the input from 20V to 25V raises the output by 0.5mV (from 12V to 12.0005V) then raising the input to 30V means that the output goes up 1mV to 12.001V. I think it was your mistaken introduction of 'proportional' which led you astray.
 3rd July 2012, 06:42 PM #92 Wavebourn   Designer & Technologist diyAudio Member     Join Date: Sep 2006 Location: Pleasant Hill, CA Linear voltage regulator is opposed to the one that uses PWM. But who is well known vendor of chips for PWM regulators? A company with "Linear" in their name. __________________ The Devil is not so terrible as his math model is!
 3rd July 2012, 06:44 PM #93 wahab   diyAudio Member   Join Date: Nov 2009 Location: algeria/france "Bootstrap" is one of the worse technical terms since it s barely analytical.
 3rd July 2012, 06:49 PM #94 Wavebourn   Designer & Technologist diyAudio Member     Join Date: Sep 2006 Location: Pleasant Hill, CA What is confusing in bootstrap? __________________ The Devil is not so terrible as his math model is!
 3rd July 2012, 06:50 PM #95 MarcelvdG   diyAudio Member   Join Date: Mar 2003 Location: Haarlem, the Netherlands No, you are confusing linear with affine. When there is a constant bias involved, the system does not comply with the superposition theorem anymore and it is therefore not linear. At least that's what I've been thought at the Delft University of Technology. Current feedback has at least three different meanings nowadays: -In the oldest literature that I've read, it meant series feedback at the output, no matter what happens at the input. -In the book/PhD thesis of Ernst Nordholt it means series feedback at the output and shunt feedback at the input, resulting in an accurate current to current transfer. -In the context of current feedback op-amps it applies to the exact same feedback configuration as normal voltage feedback (shunt at the output, series at the input), but with an op-amp having a low open-loop input impedance at its negative input.
Osvaldo de Banfield
diyAudio Member

Join Date: Dec 2011
Location: Barrio Garay,Almirante Brown, Buenos Aires, Argentina
Quote:
 Originally Posted by Wavebourn Linear voltage regulator is opposed to the one that uses PWM. But who is well known vendor of chips for PWM regulators? A company with "Linear" in their name.
And what if I use a quadratic device like a FET or tube? It has some proportionality, but not necessarily linear (equal output measure per equal input measure)
__________________
Osvaldo F. Zappacosta. Electronic Engineer UTN FRA from 2001.
Argentine Ham Radio LW1DSE since 1987.

wahab
diyAudio Member

Join Date: Nov 2009
Location: algeria/france
Quote:
 Originally Posted by Wavebourn What is confusing in bootstrap?
It is not analytical ethymologicaly speaking.

"Positive feedback loop" is the right term and it s quite remotely

 3rd July 2012, 07:34 PM #98 Wavebourn   Designer & Technologist diyAudio Member     Join Date: Sep 2006 Location: Pleasant Hill, CA Right, bootstrap is actually a jargon term for specific positive feedback from output of the voltage follower to it's input. __________________ The Devil is not so terrible as his math model is!
DF96
diyAudio Member

Join Date: May 2007
Quote:
 Originally Posted by MarceldvG No, you are confusing linear with affine.
Possibly. I think UK EEs generally extend 'linear' to include 'affine', as 'affine' is not a word which crops up often on EE courses here. 'Linear' is taken to mean 'no new frequency components in the output'.

Interestingly, the strict definition of linear excludes all sources (e.g. DC PSU, AC oscillators) so may be mathematically correct but perhaps unhelpful?

wahab
diyAudio Member

Join Date: Nov 2009
Location: algeria/france
Quote:
 Originally Posted by DF96 No contradiction at all. Linearity does not necessarily imply large output, and it does not necessarily require simple proportionality as a constant bias can be involved too. All linearity, in the context of a PSU, means is that if raising the input from 20V to 25V raises the output by 0.5mV (from 12V to 12.0005V) then raising the input to 30V means that the output goes up 1mV to 12.001V.
Linearity of such PSU is not tied to its regulation factor seen from
input to output but to the relation between its voltage reference
and its output.

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Forum Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Site     Site Announcements     Forum Problems Amplifiers     Solid State     Pass Labs     Tubes / Valves     Chip Amps     Class D     Power Supplies     Headphone Systems Source & Line     Analogue Source     Analog Line Level     Digital Source     Digital Line Level     PC Based Loudspeakers     Multi-Way     Full Range     Subwoofers     Planars & Exotics Live Sound     PA Systems     Instruments and Amps Design & Build     Parts     Equipment & Tools     Construction Tips     Software Tools General Interest     Car Audio     diyAudio.com Articles     Music     Everything Else Member Areas     Introductions     The Lounge     Clubs & Events     In Memoriam The Moving Image Commercial Sector     Swap Meet     Group Buys     The diyAudio Store     Vendor Forums         Vendor's Bazaar         Sonic Craft         Apex Jr         Audio Sector         Acoustic Fun         Chipamp         DIY HiFi Supply         Elekit         Elektor         Mains Cables R Us         Parts Connexion         Planet 10 hifi         Quanghao Audio Design         Siliconray Online Electronics Store         Tubelab     Manufacturers         AKSA         Audio Poutine         Musicaltech         Aussie Amplifiers         CSS         exaDevices         Feastrex         GedLee         Head 'n' HiFi - Walter         Heatsink USA         miniDSP         SITO Audio         Twin Audio         Twisted Pear         Wild Burro Audio

 Similar Threads Thread Thread Starter Forum Replies Last Post alaskanaudio Solid State 36 1st June 2014 02:35 AM ninopelo29 Instruments and Amps 6 9th December 2011 01:38 AM hags Swap Meet 2 1st October 2010 08:45 PM Cyberzim Class D 7 12th November 2009 09:53 AM

 New To Site? Need Help?

All times are GMT. The time now is 07:08 AM.