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Is C2 here to protect the voltage source from thermal noise? There's absolutely no chance that any level of thermal noise produced by a resistor will be sufficient to cause any reasonably desi...
Answer
#2: Post edited
by
Andy aka
·
2023-05-10T12:00:31Z (over 1 year ago)
- > _Is C2 here to protect the voltage source from thermal noise?_
- There's absolutely no chance that any level of thermal noise produced by a resistor will be sufficient to cause any reasonably designed power supply (voltage source) any problems whatsoever. Even badly designed power supplies will cope with this easily.
- For instance if R1+R2 was 1 MΩ and they were heated up to 200 °C, the open circuit noise they would produce is 161 μV. That's a piddling amount of noise and power.
Also, consider this; a power supply is a practical voltage source and, will almost certainly have several to hundreds or thousands of micro-farads of capacitance already across its output terminals so, what do you think the presence of another capacitor is going to bring to the party?
- > _Is C2 here to protect the voltage source from thermal noise?_
- There's absolutely no chance that any level of thermal noise produced by a resistor will be sufficient to cause any reasonably designed power supply (voltage source) any problems whatsoever. Even badly designed power supplies will cope with this easily.
- For instance if R1+R2 was 1 MΩ and they were heated up to 200 °C, the open circuit noise they would produce is 161 μV. That's a piddling amount of noise and power.
- Also, consider this; a power supply is a practical voltage source and, will almost certainly have several, to hundreds, or thousands of micro-farads of capacitance already across its output terminals so, what do you think the presence of another capacitor is going to bring to the party?
#1: Initial revision
by
Andy aka
·
2023-05-10T11:59:33Z (over 1 year ago)
> _Is C2 here to protect the voltage source from thermal noise?_ There's absolutely no chance that any level of thermal noise produced by a resistor will be sufficient to cause any reasonably designed power supply (voltage source) any problems whatsoever. Even badly designed power supplies will cope with this easily. For instance if R1+R2 was 1 MΩ and they were heated up to 200 °C, the open circuit noise they would produce is 161 μV. That's a piddling amount of noise and power. Also, consider this; a power supply is a practical voltage source and, will almost certainly have several to hundreds or thousands of micro-farads of capacitance already across its output terminals so, what do you think the presence of another capacitor is going to bring to the party?