IoT Sensor Interfacing

Scope

Sensor engineering interfaces analog and digital transducers with microcontrollers, applying amplification, analog filtering, analog-to-digital conversion, and digital calibration.

Signal Conditioning & Digital Sensors

• Analog Signal Conditioning: Operational amplifiers in non-inverting, differential, and instrumentation configurations ($V_{\text{out}} = \frac{R_4}{R_3}(V_2 - V_1)$). Anti-aliasing active low-pass filtering (Butterworth) prior to ADC sampling ($f_c < f_s / 2$).
• ADC Metrics: Resolution $n$ bits, Quantization step $q = V_{\text{ref}} / 2^n$, Signal-to-Noise Ratio $\text{SNR} = 6.02 n + 1.76\text{ dB}$.
• Digital MEMS Sensors: Interfacing accelerometers, gyroscopes, magnetometers, barometers, and humidity sensors over I2C/SPI; register polling vs. data-ready interrupt thresholds.

Tools & References

• Canonical References: Fraden — Handbook of Modern Sensors: Physics, Designs, and Applications.