Features: [Automatic Gains Control]Built-in automatic gains control function provides three selectable gains setting of 40dB, 50dB, and 60dB, ensuring clear auditory input in various environments. [Broad-Spectrum Compatibility Design]Compatible with various development boards such as ESP8266, facilitating seamless integration with existing projects without the need for additional adapters. [Low-Noise Performance]Low input reference noise density of just 30nV, delivering purer audiory and reducing background noise interferences. [Wide Voltages Ranging]Supports power supply voltages from 2.7V to 5.5V, flexibly adapting to various power supply conditions and enhancing device compatibility. [Fast Response Capability]Programmable attack and release ratios ensuring rapid response to auditory changes, maintaining natural and smooth sound. Specifications: Automatic Gains Control () 3 gains setting (40dB, 50dB, 60dB) Programmable action time Programmable action and release time ratio 2.7V to 5.5V supply voltages ranges Low input noise density 30nV Low THD: 0.04% (typical) With 2V low noise microphone bias 14-pin TDFN (3mm x 3mm) package Power supply voltages: 2.7v-5.5v @ 3mA current Output: 2Vpp at 1.25V bias Frequency response: 20Hz-20 KHz Automatic, up to 40dB, 50dB or 60dB Size:about 25.4x14mm/1x0.55in Package Includes: 1 Set MAX9814 microphone amplifier board note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.