Analog vs. Digital Microphone Sensitivity: Definition & Equations

microphone
sensitivity
analog
digital
audio

This article explains the difference between analog and digital microphone sensitivity. It also provides the equations used to define each type of microphone sensitivity.

Sensitivity Definition: Sensitivity is defined as the ratio of the analog output voltage (for analog microphones) or the digital output value (for digital microphones) to the input pressure. It’s a crucial parameter for any microphone.

microphone sensitivity

The equation for microphone sensitivity is as follows:

Sensitivity=Output SignalInput Pressure\text{Sensitivity} = \frac{\text{Output Signal}}{\text{Input Pressure}}

Typically, microphone sensitivity is measured using a 1 kHz sine wave at 94 dB SPL (Sound Pressure Level) or 1 Pa (Pascal) pressure. As mentioned, sensitivity is determined by measuring the magnitude of the analog or digital output signal from the microphone in response to a specific input sound stimulus.

Analog Microphone Sensitivity

analog microphone sensitivity

The sensitivity of an analog microphone is calculated using the following equation:

Sensitivity (mV/Pa)=Output Voltage (mV)Input Pressure (Pa)\text{Sensitivity (mV/Pa)} = \frac{\text{Output Voltage (mV)}}{\text{Input Pressure (Pa)}}

The unit for analog microphone sensitivity is mV/Pa in linear units.

This can also be expressed in dBV (decibels relative to 1 Volt) using the following equation:

Sensitivity (dBV)=20log10(OutputAREF)\text{Sensitivity (dBV)} = 20 \cdot \log_{10} \left( \frac{\text{Output}}{\text{AREF}} \right)

Where Output AREF is equal to a reference output ratio of 1000 mV/Pa (i.e., 1 V/Pa).

Digital Microphone Sensitivity

digital microphone sensitivity

The sensitivity of a digital microphone is calculated using the following equation:

\text{Sensitivity (%)}= \frac{\text{Digital Output Value}}{\text{Full Scale Output}} \cdot 100 \%

It’s measured as a percentage of the full-scale output generated by a 94 dB SPL input.

As the output units of analog and digital microphones are different, it can be challenging to directly compare the performance of these two types of microphones.

MEMS Microphone: Advantages and Disadvantages

MEMS Microphone: Advantages and Disadvantages

Explore the benefits and drawbacks of MEMS (Micro-Electro-Mechanical Systems) microphones, their working principles, and comparison with condenser microphones.

mems
microphone
sensor
Condenser Microphone: Advantages and Disadvantages

Condenser Microphone: Advantages and Disadvantages

Explore the benefits and drawbacks of condenser microphones (capacitor microphones), including working principles, sensitivity, frequency response, and power requirements.

condenser microphone
microphone
audio
Dynamic Microphones: Advantages and Disadvantages

Dynamic Microphones: Advantages and Disadvantages

Explore the pros and cons of dynamic microphones (moving coil mics), including their affordability, durability, and sound coloring, as well as limitations in high-frequency response and sensitivity.

microphone
dynamic microphone
audio
Hybrid Beamforming: Advantages and Disadvantages

Hybrid Beamforming: Advantages and Disadvantages

Explore the pros and cons of hybrid beamforming, a technique combining analog and digital beamforming for enhanced coverage and flexibility in wireless communication systems.

hybrid beamforming
beamforming
wireless communication