1
\$\begingroup\$

I am studying the construction of some touch sensors, and I need inductances of 10mH, I know I can easily do it, and also purchase them without much difficulty, however I know that it is possible to simulate such inductances using a circuit called Gyrator.

What would be the pros and cons of replacing a passive inductor by a simulated inductor with Gyrator.

\$\endgroup\$
1
  • 2
    \$\begingroup\$ Gyrators are not susceptible to alternating magnetic fields. \$\endgroup\$
    – Al Bundy
    May 26 '15 at 20:37
1
\$\begingroup\$

The major disadvantage of a gyrator is that it needs DC power and a DC bias to set the circuit up correctly. The advantage of an inductor of course is that this is not needed.

Another disadvantage of a gyrator is that they are all (from what I've seen of the simple transistor/op-amp type) all ground referenced at one end of the inductor i.e. if you wanted an inductor that was ungrounded on both pins then it becomes a lot more complex.

Many inductors are used in power applications (such as switch mode power supplies). In simple words, gyrators are useless in these applications.

The main area that I see a lot of gyrators used is in audio graphic equalizers where a low power and low to medium Q factor is needed. Also frequencies are moderately low i.e. limited to no-more than 20kHz.

\$\endgroup\$
10
  • \$\begingroup\$ I did not know this limitation, performance, up to 20khz, which impacts a lot on my choice. Regarding the interference as 10 subcircuits using the gyrator, there is much interference as may occur with conventional inductors? \$\endgroup\$
    – Delfino
    May 26 '15 at 20:46
  • 1
    \$\begingroup\$ Gyrators can work very much higher than 20kHz - I was giving an example where they are used a lot. \$\endgroup\$
    – Andy aka
    May 26 '15 at 21:18
  • \$\begingroup\$ @Andyaka Are SMPS out because they require the use of the magnetic feild or is it the switching speed that is why they are out ? \$\endgroup\$
    – efox29
    May 26 '15 at 22:48
  • 1
    \$\begingroup\$ @efox29: Technically, SMPS's don't require magnetic fields. What they require is kinetic energy storage. They work by converting potential energy to kinetic, and back to potential. Gyrators, unfortunately, don't store any energy -- neither potential nor kinetic. \$\endgroup\$
    – Zulu
    May 27 '15 at 2:07
  • 1
    \$\begingroup\$ @Zulu if they don't require magnetic feilds, then a capacitor could be used in some sort of topology as well in SMPS - do they have a topology like that ? \$\endgroup\$
    – efox29
    May 27 '15 at 2:12

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.