Verification of extremely small signals

QWE4562009

Verification of extremely small signals [Copy link]

Verification of extremely small signals
Generally, signals within 100mV are called small signals, but there are even weaker signals at the UV level. For example, the voltage output by the temperature gun sensor is at the uV level. Even if such a weak signal is amplified, it will cause a large deviation due to the error of resistors or other components. So how can we verify how big this signal is? What are some reliable methods?

maychang

The answer is already given in the picture you posted: chopper-stabilized zero op amp.

Gen_X

High-gain amplification is generally used, but it also amplifies interference, especially when common-mode suppression requirements are high.

Therefore, a low-drift instrumentation amplifier is used, which has better common-mode resistance, higher input impedance,

Smaller temperature and higher gain stability.

It’s better to copy it first, don’t just “design” it!

QWE4562009

maychang posted on 2021-6-21 19:55 The answer is given in the picture you posted: chopper-stabilized zero op amp.

I mean how to verify the tiny signal of 1uV

QWE4562009

Gen_X Published on 2021-6-22 09:44 High gain amplification is generally used, but it also amplifies interference, especially when common mode rejection requirements are high. Therefore, a low drift instrumentation amplifier is used, which has a better...

Yes, any interference is a few mV, Shenzhen has dozens of mV, so how to distinguish whether it is a valid signal or interference?