NOISE MEASUREMENT CIRCUIT

The LM4562 is a high speed op amp with excellent phase

margin and stability. Capacitive loads up to 100pF will cause

little change in the phase characteristics of the amplifiers

and are therefore allowable.

Capacitive loads greater than 100pF must be isolated from

the output. The most straightforward way to do this is to put

a resistor in series with the output. This resistor will also

prevent excess power dissipation if the output is accidentally

shorted.

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Complete shielding is required to prevent induced pick up from external sources. Always check with oscilloscope for power line noise.

Input Referred Noise Voltage: e

RIAA Preamp Voltage Gain, RIAA

Deviation vs Frequency

Flat Amp Voltage Gain vs

Frequency

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