ADA4177: What resistor values should I use around the amplifier?

Document created by DanB Employee on Mar 2, 2015
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ADA4177 has a low voltage noise density of 8 nV/√Hz, only twice the Johnson noise of a 1kΩ resistor.  Placing a 1KΩ resistor with thermal noise of 4 nV/√Hz at the input of the amplifier increases total input referred noise to 8.9 nV/√Hz.  It is important to use low value resistors around a low-noise amplifier.