Description
A capacitance multiplier circuit is implemented with an operational amplifier opa725. The effective value of a small capacitor C1 is increased to a much larger value, The capacitance seen at Vout is: Cout = C1 * R1/R3. For C1=100pF, the resulting capacitance is 100nF. The output capacitance can be verified with the cutoff frequency of resulting R-C circuit, Fc= 1/(6.28*R*C) =1.59 Hz.
- Free
- Simple
- <10
- TINA
- 7+
- No
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paulcardno –
Hey TINADesign Thanks for this design. Just starting to understand cap multiplier and your design is interesting, thanks for that. Questions.1) there appear to be two R3 resistors, I assume that the top R3 resistor between opamp negative and output is actually R2. thanks again Paul
TINADesigner –
Yes you are right, the name of the top R3 was mistyped. I’ve changed it to R5. Note that now you can also run this example with the on-line version of TINA called TINACloud, change the component parameters and see the effect of the changes. Best regards Michael DesignSoft