Product description
EK022 is an amplifier for electret microphones. A microphone is included in the kit and is mounted directly on the circuit board. The kit contains all the components needed to power the microphone and amplify the signal to a level suitable for use with a microcontroller or audio equipment. If capacitor C5 is installed, the output will be AC-coupled and suitable for use with mixers, amplifiers, or other audio equipment. For use with a microcontroller or other electronics with standard logic levels, the two connections should instead be bridged with a component lead. In this case, the output will be DC-coupled and swing between 0V and V+, centered around half of the supply voltage. The gain is set to 100x but can be adjusted by replacing the feedback resistor in the amplifier (R3). The gain can be calculated using the formula G = R2/R3 (1kΩ/100kΩ = 100x gain). The included microphone has a sensitivity of -50dBu, which translates to 3.16mV/Pa. To provide a usable signal, it needs significant amplification! The TLC271 operational amplifier used in the kit supports a wide voltage range and can be powered with voltages from 3V up to 12V.
- Supply voltage: 3 - 12 VDC
- Current consumption: 2.2mA (@ 12V)
- Dimensions: 38 x 25mm
- Mounting holes: c-c 33 x 20mm, ø2.5mm
