Ultra low noise electret microphones pre-amp amplification board, using ST imported K472 electret microphones special amplifier chip, chip with low noise. Gain adjustable, power supply wide,and can be difference output, can also be single-ended output.
Gain adjustment: resistance R3 is gain adjustment resistance, when the default delivery is 30 db (resistance to 1 k), if not appropriate, can consult the table below change R3 resistance to obtain different gain, changes the resistance when the need to take off the original R3 SMD resistor (if you feel bad patch welding, welding the R3 can also use the plug-in beside two reserved welding plate above (gain is 0 to 40 db variable).
Microphones connected: microphones positive + and negative -, GND on the board as a shield, don't need connected microphones (also can not meet, meet, but it is better to avoid interference)
Difference Output: connect signal +, -, middle is GND grounded.Single-ended output: connect signal +, middle GND connect groundingDual -channel output : signal +when a channel, signal - when a track, GND grounding in the middle
Three kinds of output connection can choose according to needOperating voltage: DC 2.3 V to 5.5 V
Material: PC + metal
Product size: 2.3*1.5cm
1*Microphone Power Amplifier Board
Only the above package content, other products are not included.
Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.