Analysis of a Direct Microcontroller Interface for Capacitively Coupled Resistive Sensors

Microcontroller-based interface circuit for inductive sensors

This work proposes a fully-digital interface circuit for the measurement of inductive sensors using a low-cost microcontroller (μC) and without any intermediate active circuit. Apart from the μC and the sensor, the circuit just requires an external resistor and a reference inductance so that two RL circuits with a high-pass filter (HPF) topology are formed. The μC appropriately excites such RL ...

A smart and accurate interface for resistive sensors

This paper presents a smart and accurate interface for resistive sensors based on the use of a relaxation oscillator. To obtain high accuracy, good long-term stability and a reduction of the effects of interference and parasitic elements, some classical and new measurement techniques have been applied in the novel sensor interface. Moreover, all multiplicative and additive errors, and the commo...

Direct Inductive Sensor - to - Microcontroller Interface Circuit

Calibration-less direct capacitor-to- microcontroller interface

A new technique to measure a capacitor or a capacitive sensor by means of a direct sensor-to-microcontroller interface circuit that does not need a calibration capacitor is proposed. Basically, the measurement process consists of three consecutive steps of charge, discharge and charge of the capacitor under test. A non-linear equation is obtained and solved that is dependent only on known circu...

Charge-transfer-based Signal Interface for Resistive Sensors

 Charge transfer has been demonstrated to be a cost-effective method to measure capacitive sensors with low-end microcontrollers. Here we apply charge transfer to measure the output of voltage dividers that include a highvalue resistive sensor hence extending the advantages of this method to a large group of sensors. By using two-point calibration, the maximal deviation obtained, referred to t...