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Analog division, current conveyors and SPICE

Started by Unknown August 15, 2014
Could some analog/SPICE guru please help ?
I am running SPICE simulations on current
conveyors, focusing analog computation. 
Specifically, I am examining in detail 
analog division. I am referring to Sedra 
and Smith's 1970 paper.

Given that a negative impedance converter
shifts the phase of the input signal by 180 
degrees, what would be the effect of analog
division of one signal by another ? 
Specifically how should the output look like?
For example, if s11, s12, s13, s14, x15, ...
and s21, s22, s23, s24, ... etc., are 
respectively the input signal values, should
the output signal be simply s11/s12, x12/s22
and so on ?
Any hints, suggestions would be of immense 
help. Thanks in advance.

 
  
On Thu, 14 Aug 2014 21:52:21 -0700 (PDT), dakupoto@gmail.com wrote:

>Could some analog/SPICE guru please help ? >I am running SPICE simulations on current >conveyors, focusing analog computation. >Specifically, I am examining in detail >analog division. I am referring to Sedra >and Smith's 1970 paper.
Current conveyors are just a hokey name invention by PhD's to make ideal current mirrors into something magical >:-}
> >Given that a negative impedance converter >shifts the phase of the input signal by 180 >degrees, what would be the effect of analog >division of one signal by another ? >Specifically how should the output look like? >For example, if s11, s12, s13, s14, x15, ... >and s21, s22, s23, s24, ... etc., are >respectively the input signal values, should >the output signal be simply s11/s12, x12/s22 >and so on ? >Any hints, suggestions would be of immense >help. Thanks in advance. > > >
What are you actually trying to accomplish? ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
On 2014-08-15, dakupoto@gmail.com <dakupoto@gmail.com> wrote:
> Could some analog/SPICE guru please help ? > I am running SPICE simulations on current > conveyors, focusing analog computation. > Specifically, I am examining in detail > analog division. I am referring to Sedra > and Smith's 1970 paper. > > Given that a negative impedance converter > shifts the phase of the input signal by 180 > degrees, what would be the effect of analog > division of one signal by another ?
division by zero.
> Specifically how should the output look like?
real world or idealised?
> Any hints, suggestions would be of immense > help. Thanks in advance.
don't go there. -- umop apisdn --- news://freenews.netfront.net/ - complaints: news@netfront.net ---
On Friday, August 15, 2014 1:02:01 PM UTC-4, Jim Thompson wrote:
> On Thu, 14 Aug 2014 21:52:21 -0700 (PDT), dakupoto@gmail.com wrote: > > > > >Could some analog/SPICE guru please help ? > > >I am running SPICE simulations on current > > >conveyors, focusing analog computation. > > >Specifically, I am examining in detail > > >analog division. I am referring to Sedra > > >and Smith's 1970 paper. > > > > Current conveyors are just a hokey name invention by PhD's to make > > ideal current mirrors into something magical >:-} > > > > > > > >Given that a negative impedance converter > > >shifts the phase of the input signal by 180 > > >degrees, what would be the effect of analog > > >division of one signal by another ? > > >Specifically how should the output look like? > > >For example, if s11, s12, s13, s14, x15, ... > > >and s21, s22, s23, s24, ... etc., are > > >respectively the input signal values, should > > >the output signal be simply s11/s12, x12/s22 > > >and so on ? > > >Any hints, suggestions would be of immense > > >help. Thanks in advance. > > > > > > > > > > > > > What are you actually trying to accomplish? > > > > ...Jim Thompson > > -- > > | James E.Thompson | mens | > > | Analog Innovations | et | > > | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | > > | San Tan Valley, AZ 85142 Skype: skypeanalog | | > > | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | > > | E-mail Icon at http://www.analog-innovations.com | 1962 | > > > > I love to cook with wine. Sometimes I even put it in the food.
Current conveyors are used in active impedance matching, also in some instrumentation amplifiers. and filters. Some have claimed that they may be used in analog computation. I am trying to simulate/understand signal division and multiplication with current conveyors. Right now it is all one quadrant, but later I intend to push to more quadrant operation.
On Fri, 15 Aug 2014 22:47:37 -0700 (PDT), dakupoto@gmail.com wrote:

>On Friday, August 15, 2014 1:02:01 PM UTC-4, Jim Thompson wrote: >> On Thu, 14 Aug 2014 21:52:21 -0700 (PDT), dakupoto@gmail.com wrote: >> >> >> >> >Could some analog/SPICE guru please help ? >> >> >I am running SPICE simulations on current >> >> >conveyors, focusing analog computation. >> >> >Specifically, I am examining in detail >> >> >analog division. I am referring to Sedra >> >> >and Smith's 1970 paper. >> >> >> >> Current conveyors are just a hokey name invention by PhD's to make >> >> ideal current mirrors into something magical >:-} >> >> >> >> > >> >> >Given that a negative impedance converter >> >> >shifts the phase of the input signal by 180 >> >> >degrees, what would be the effect of analog >> >> >division of one signal by another ? >> >> >Specifically how should the output look like? >> >> >For example, if s11, s12, s13, s14, x15, ... >> >> >and s21, s22, s23, s24, ... etc., are >> >> >respectively the input signal values, should >> >> >the output signal be simply s11/s12, x12/s22 >> >> >and so on ? >> >> >Any hints, suggestions would be of immense >> >> >help. Thanks in advance. >> >> > >> >> > >> >> > >> >> >> >> What are you actually trying to accomplish? >> >> >> >> ...Jim Thompson >> >> -- >> >> | James E.Thompson | mens | >> >> | Analog Innovations | et | >> >> | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | >> >> | San Tan Valley, AZ 85142 Skype: skypeanalog | | >> >> | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | >> >> | E-mail Icon at http://www.analog-innovations.com | 1962 | >> >> >> >> I love to cook with wine. Sometimes I even put it in the food. > >Current conveyors are used in >active impedance matching, also >in some instrumentation amplifiers. >and filters. Some have claimed >that they may be used in analog >computation. I am trying to >simulate/understand signal division >and multiplication with current >conveyors. Right now it is all >one quadrant, but later I intend >to push to more quadrant operation.
Division is always risky... read, for instance, the AD633 datasheet. The are 8 items on the S.E.D/Schematics Page of my website devoted to "gyrators"... analyzing those _by_hand_ will provide some insight. ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.