I read many conflicting accounts. The common belief seems to be "thermal noise increases with a larger resistance value, whereas current noise decreases when resistance increases."
But a web site mentioned this is just a myth (see below).
https://www.analog.com/en/resources/technical-articles/11-myths-about-analog-noise-analysis.html
"
8. The Amplifier with the Lowest Voltage Noise Is the Best Choice
"When choosing an op amp, the voltage noise is often the only noise specification considered by the designer. It is important not to overlook the current noise as well. Except in special cases such as input bias current compensation, the current noise is typically the shot noise of the input bias current: in = √2 × q × IB. The current noise is converted to a voltage via the source resistance, so when there is a large resistance in front of the amplifier input, the current noise can be a larger noise contributor than the voltage noise. "
So what kind of circuit where, as the resistance increases, the current noise decreases?
What kind of circuit where, as the resistance increases, the current noise also increases?
But a web site mentioned this is just a myth (see below).
https://www.analog.com/en/resources/technical-articles/11-myths-about-analog-noise-analysis.html
"
8. The Amplifier with the Lowest Voltage Noise Is the Best Choice
"When choosing an op amp, the voltage noise is often the only noise specification considered by the designer. It is important not to overlook the current noise as well. Except in special cases such as input bias current compensation, the current noise is typically the shot noise of the input bias current: in = √2 × q × IB. The current noise is converted to a voltage via the source resistance, so when there is a large resistance in front of the amplifier input, the current noise can be a larger noise contributor than the voltage noise. "
So what kind of circuit where, as the resistance increases, the current noise decreases?
What kind of circuit where, as the resistance increases, the current noise also increases?