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Bumped by Community user
Bumped by Community user
Bumped by Community user
deleted 1 character in body; edited title
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JRE
JRE
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Why isdoes this NICnegative impedance converter (Negative Impedance ConverterNIC) circuit simulation workingwork in LTSpice,an LTspice simulation but not in an actual circuit?

I've been trying to invert the phase response of a non-inverting low pass filter by using a "negative resistor" (-5000 ohms),) which is achieved by the simulation below (bode plot + circuit): enter image description here

enter image description here

However, whenWhen I built the circuit (usingusing LM358 op amps), the NIC makes the original low pass filter circuit lose its output signal. (I've

I've also noticed that the NIC makes the power supply for the first op amp, U1, behave erratically - i.e. the negative voltage supply pings left when I turn on the positive voltage supply).

I use a different power supply for each op amp, and the power supply pins on both op amps have decoupling capacitors in place. 

Could the NIC circuit just not be usable in the actual circuit?

Why is this NIC (Negative Impedance Converter) circuit simulation working in LTSpice, but not in an actual circuit?

I've been trying to invert the phase response of a non-inverting low pass filter by using a "negative resistor" (-5000 ohms), which is achieved by the simulation below (bode plot + circuit): enter image description here

enter image description here

However, when I built the circuit (using LM358 op amps), the NIC makes the original low pass filter circuit lose its output signal. (I've also noticed that the NIC makes the power supply for the first op amp, U1, behave erratically - i.e. the negative voltage supply pings left when I turn on the positive voltage supply) I use a different power supply for each op amp, and the power supply pins on both op amps have decoupling capacitors in place. Could the NIC circuit just not be usable in the actual circuit?

Why does this negative impedance converter (NIC) circuit work in an LTspice simulation but not in an actual circuit?

I've been trying to invert the phase response of a non-inverting low pass filter by using a "negative resistor" (-5000 ohms,) which is achieved by the simulation below (bode plot + circuit): enter image description here

enter image description here

When I built the circuit using LM358 op amps, the NIC makes the original low pass filter circuit lose its output signal.

I've also noticed that the NIC makes the power supply for the first op amp, U1, behave erratically - i.e. the negative voltage supply pings left when I turn on the positive voltage supply.

I use a different power supply for each op amp, and the power supply pins on both op amps have decoupling capacitors in place. 

Could the NIC circuit just not be usable in the actual circuit?

Bumped by Community user
Bumped by Community user
Ohm = surname. ohm = unit of resistance.
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winny
winny
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I've been trying to invert the phase response of a non-inverting low pass filter by using a "negative resistor" (-5000 Ohmsohms), which is achieved by the simulation below (bode plot + circuit): enter image description here

enter image description here

However, when I built the circuit (using LM358 op amps), the NIC makes the original low pass filter circuit lose its output signal. (I've also noticed that the NIC makes the power supply for the first op amp, U1, behave erratically - i.e. the negative voltage supply pings left when I turn on the positive voltage supply) I use a different power supply for each op amp, and the power supply pins on both op amps have decoupling capacitors in place. Could the NIC circuit just not be usable in the actual circuit?

I've been trying to invert the phase response of a non-inverting low pass filter by using a "negative resistor" (-5000 Ohms), which is achieved by the simulation below (bode plot + circuit): enter image description here

enter image description here

However, when I built the circuit (using LM358 op amps), the NIC makes the original low pass filter circuit lose its output signal. (I've also noticed that the NIC makes the power supply for the first op amp, U1, behave erratically - i.e. the negative voltage supply pings left when I turn on the positive voltage supply) I use a different power supply for each op amp, and the power supply pins on both op amps have decoupling capacitors in place. Could the NIC circuit just not be usable in the actual circuit?

I've been trying to invert the phase response of a non-inverting low pass filter by using a "negative resistor" (-5000 ohms), which is achieved by the simulation below (bode plot + circuit): enter image description here

enter image description here

However, when I built the circuit (using LM358 op amps), the NIC makes the original low pass filter circuit lose its output signal. (I've also noticed that the NIC makes the power supply for the first op amp, U1, behave erratically - i.e. the negative voltage supply pings left when I turn on the positive voltage supply) I use a different power supply for each op amp, and the power supply pins on both op amps have decoupling capacitors in place. Could the NIC circuit just not be usable in the actual circuit?

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tupsman
tupsman
  • 1

Why is this NIC (Negative Impedance Converter) circuit simulation working in LTSpice, but not in an actual circuit?

I've been trying to invert the phase response of a non-inverting low pass filter by using a "negative resistor" (-5000 Ohms), which is achieved by the simulation below (bode plot + circuit): enter image description here

enter image description here

However, when I built the circuit (using LM358 op amps), the NIC makes the original low pass filter circuit lose its output signal. (I've also noticed that the NIC makes the power supply for the first op amp, U1, behave erratically - i.e. the negative voltage supply pings left when I turn on the positive voltage supply) I use a different power supply for each op amp, and the power supply pins on both op amps have decoupling capacitors in place. Could the NIC circuit just not be usable in the actual circuit?