Junus2012
Advanced Member level 5
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Hello,
I need to amplify a small sensor signal that have a maximum signal level of 5 mV and bandwidth of up to 100 kHz. The gain accuracy should be 1%.
I want to design an opamp using the 180 nm technology powered by single supply voltage of 1.8 V. The opamp is then driving the fully differential input ADC.
I started like this
To cover the full-scale window of the ADC, the opamp should have a closed loop gain of 1.8/5 mV = 50 dB.
To have a gain accuracy of 1% I should have a loop gain that is 20 db (100) above the 50 dB for the complete bandwidth of the input signal, that is 70 dB at least.
However, since the opamp gain roll off with frequency, the gain-bandwidth product should be more important to consider.
Please help me to determine the required GBW of the opamp to condition this signal and also the required slew rate
Thank you
Regards
I need to amplify a small sensor signal that have a maximum signal level of 5 mV and bandwidth of up to 100 kHz. The gain accuracy should be 1%.
I want to design an opamp using the 180 nm technology powered by single supply voltage of 1.8 V. The opamp is then driving the fully differential input ADC.
I started like this
To cover the full-scale window of the ADC, the opamp should have a closed loop gain of 1.8/5 mV = 50 dB.
To have a gain accuracy of 1% I should have a loop gain that is 20 db (100) above the 50 dB for the complete bandwidth of the input signal, that is 70 dB at least.
However, since the opamp gain roll off with frequency, the gain-bandwidth product should be more important to consider.
Please help me to determine the required GBW of the opamp to condition this signal and also the required slew rate
Thank you
Regards