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https://designers-guide.org/forum/YaBB.pl Measurements >> Other Measurements >> Measure Equivalent Input Voltage and Current Noise of Op Amps https://designers-guide.org/forum/YaBB.pl?num=1551337485 Message started by ZY He on Feb 27^{th}, 2019, 11:04pm |
Title: Measure Equivalent Input Voltage and Current Noise of Op Amps Post by ZY He on Feb 27^{th}, 2019, 11:04pm Hello, Recently i learn a few about the noise model about operational amplifier. And here i have some questions about how to understand the measure of equivalent input voltage noise and equivalent input current noise of an operational amplifiers in Noise analysis in Virtuoso ADE. I want to know: 1. what is the noise model of an amplifier in ADE simulation 2. how they define the equivalent input voltage noise and equivalent input current noise 3. is there any relationship between equivalent input VOLTAGE noise and equivalent input CURRENT noise Are there any helpful documents about it? Please help me!! Thank you very much. ;D |
Title: Re: Measure Equivalent Input Voltage and Current Noise of Op Amps Post by Andrew Beckett on Mar 1^{st}, 2019, 1:01am Attempting to answer your questions: [olist] [/olist] Regards, Andrew |
Title: Re: Measure Equivalent Input Voltage and Current Noise of Op Amps Post by ZY He on Mar 1^{st}, 2019, 10:59pm Thank you Andrew. 1. The reason why i mention the noise model of an Op Amp is in some case, i will assume there are a series noise voltage source 'Vn' and a shunt noise current source 'In' for each input port of an Op Amp. I just thought that Noise Analysis will calculate these two noise sources as equivalent input voltage and current noise source. 2. 'they' is noise analysis in ADE. But now i know how the noise analysis works. 3. now i have another question. If there is a noiseless voltage source Vs with an source resistance Rs as the input source of an Op Amp, how should i define the noise caused by the input source Vs & Rs. Should i consider equivalent input current source Ien multiply by Rs? |
Title: Re: Measure Equivalent Input Voltage and Current Noise of Op Amps Post by Andrew Beckett on Mar 2^{nd}, 2019, 6:55am I have no idea what you mean by your new question. It doesn't make any sense to me, so I've no idea how to answer it. For example, if the voltage source is noiseless, it won't cause any noise. The source resistance Rs would generate thermal noise (unless you've explicitly turned off noise for that resistor). Beyond that I don't really understand what you're getting at with your questions. Regards, Andrew. |
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