AD8137 gain

Question

Hi, 
 I'm trying to get a gain of 10 from an AD81237 using 1k resistors for Rg and 10k resistors for Rf. Powering the amplifier with 5V single voltage, non inverting output goes about 300mV and inverting output goes 4.6V, with or without input signal. If I use all 1k resistors for Rg and Rf the gain is 1V/V and all works fine, but there is no way to have a gain of 10 V/V. Can anyone help me? Thank you tools.analog.com/.../

Achim · Accepted Answer

well, looking at the circuit again: in the Gain=10 seupt you're violating the input common mode range specification (which requires the input voltages to be 1V above the negative supply). In your Gain=1 setup, there is no violation (as the amplifier inputs are at Vocm/2=Vcc/4=1,25V). Maybe there is the reason for your results. 
 best regards 
 Achim)

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AD8137 gain