Circuit idea: Making the positive feedback dominate over the negative one.

INIC operating in bistable mode is a current-driven N-shaped true negative resistor.

Introduction

How to investigate the bistable mode of current inversion NIC

Fig. 1a: A hysteresis IV curve of current-driven INIC.

Fig. 1b: An N-shaped IV curve of voltage-driven INIC.

Investigating the circuit at ideal driving conditions

Increasing the input current

Negative input current, negative output voltage

Fig. 2a: Scanning the left bottom part (0 - 1) of the curve.

Fig. 2b: Sinking a current from INIC.

Zero input current, negative output voltage

Fig. 3a: Investigating the point 1 of the curve.

Fig. 3b: Sinking no current from INIC.

Positive input current, negative output voltage

Fig. 4a: Scanning the left top part (1 - 2) of the curve.

Fig. 4b: Injecting a current to INIC.

Voltage jump upward

...start...

Fig. 5-1a: Investigating the starting point of the voltage jump.

Fig. 5-1b: Making the op-amp "jump" to the positive rail.

...middle...

Fig. 5-2a: Scanning the top jumping path (2 - 3).

Fig. 5-2b: The op-amp "jumps" to the positive rail.

...final

Fig. 5-3a: Investigating the final point of the voltage jump upward.

Fig. 5-3b: The op-amp "calms down" at the positive rail.

Positive input current, positive output voltage

Fig. 6a: Scanning the right top part (3 - 4) of the curve.

Fig. 6b: Injecting a big current to INIC.

Decreasing the input current

Positive input current, positive output voltage

Fig. 7a: Scanning the right top part (4 - 5) of the curve.

Fig. 7b: Injecting a current to INIC.

Zero input current, positive output voltage

Fig. 8a: Investigating the point 5 of the curve.

Fig. 8b: Injecting no current to VNIC.

Negative input current, positive output voltage

Fig. 9a: Scanning the right bottom part (5 - 6) of the curve.

Fig. 9b: Sinking a current from INIC.

Voltage jump downward

...start...

Fig. 10-1a: Investigating the starting point of the voltage jump.

Fig. 10-1b: Making the op-amp "jump" to the negative rail.

...middle...

Fig. 10-2a: Scanning the bottom jumping path (6 - 7).

Fig. 10-2b: The op-amp "jumps" to the negative rail.

...final

Fig. 10-3a: Investigating the final point of the voltage jump downward.

Fig. 10-3b: The op-amp "calms down" at the negative rail.

Negative input current, negative output voltage

Fig. 11a: Scanning the left bottom part (7 - 0) of the curve.

Fig. 11b: Siniking a big current from INIC.

Investigating the circuit at real driving conditions

What is the relation with the non-inverting comparator with hysteresis?

See also

Revealing the mystery of negative impedance
Investigating the linear mode of negative impedance converters with current inversion
Negative impedance converter from Wikipedia considers NIC with current inversion (INIC).

References

External links