Low Noise Microphone preamplifier circuit Maxim

This circuit use to raise the gain to reduce noise or amplify the signal. And this circuit use IC OP27 / OP37 , this is precision opertional amplifier ,lower noise , and higher speed with the  same input ofset with drift specifications as the OP07 . Both parts have a 10 uV offset , 0.2 uV drift , and 1.8 million gain. Coupled with low voltage noise of 3.5 nV  at 10 Hz and a low 1 /f noise corner frequency of 2.7 Hz, the  OP27 / OP37 are optimized for accurate amplification of low - level signal.

 See schematic and pin configuration below :

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Output swing about 10 V into 600 Ohm. Input voltage maximum 25 V. This circuit also can use to , Low noise DC amplifiers , Microphone Amplifiers , Precision Amplifier , Tape - Head  Preamplifiers , Termocouple Amplfiers , Low - level Signal Processing , Medical instrumentation m Strain - gauge Amplifiers , High accuracy Data Acquistion.