# A Highly Robust Interface Circuit for Resistive Sensors

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## Abstract

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## 1. Introduction

## 2. Circuit Description and Operation

## 3. Proposed Circuit

## 4. Experiments and Results

## 5. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## Abbreviations

LDR | Light Dependent Resistor |

RTD | Resistance Temperature Detector |

DAQ | Data Acquisition |

R-I | Resistance-to-Current |

CCO | Current Controlled Oscillator |

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**Figure 4.**Transitions of both feedback loop. (

**a**) Ideal case; (

**b**) Deadlock situation; (

**c**) No deadlock situation.

**Figure 10.**Period as function of the sample resistors. Simulation in solid red squares, experiment in solid black circles and linear Equation (5) in solid line.

**Figure 11.**Period as function of the sample resistors. Experimental results with a power supply variation of $\pm 10\%$ from a nominal value of 5 V.

**Figure 12.**Period as function of the sample resistors. Experimental results with sweep from 3.5 to 7.5 V in the power supply.

**Figure 13.**Experimental results from two discrete component prototypes: the first implemented with transistors from the AO4614 (AO, square) family and the second from the DMC4050 family (DMC, circle). Correlation coefficient equal to 0.9956.

**Figure 14.**Histogram from the opamp variations with four different encapsulated. ${R}_{S}$ = 2.7 K$\mathsf{\Omega}$.

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**MDPI and ACS Style**

Gómez-Ramírez, E.; Maeda-Nunez, L.A.; Álvarez-Simón, L.C.; Flores-García, F.G.
A Highly Robust Interface Circuit for Resistive Sensors. *Electronics* **2019**, *8*, 263.
https://doi.org/10.3390/electronics8030263

**AMA Style**

Gómez-Ramírez E, Maeda-Nunez LA, Álvarez-Simón LC, Flores-García FG.
A Highly Robust Interface Circuit for Resistive Sensors. *Electronics*. 2019; 8(3):263.
https://doi.org/10.3390/electronics8030263

**Chicago/Turabian Style**

Gómez-Ramírez, Emmanuel, L. A. Maeda-Nunez, Luis C. Álvarez-Simón, and F. G. Flores-García.
2019. "A Highly Robust Interface Circuit for Resistive Sensors" *Electronics* 8, no. 3: 263.
https://doi.org/10.3390/electronics8030263