10

100

1k

10k

100k

FREQUENCY (Hz)

20

30

40

50

60

70

80

90

-1

0

+1

0

10

20

30

40

50

20

100

1k

10k 20k

FREQUENCY (Hz)

0.47 PF

LME49740

V1

99k

0.47 PF

27 pF

16k

200k

15 nF

4.7 nF

+

+

V2

+

-

+

-

+

-

4.7 PF

+

99k

27 pF

FLAT AMP. 40 dB + 40 dB

RIAA PREAMP

35 dB, f = 1 kHz

47 PF

47 PF

390

390

1k

39k

39k

1k

AVERAGE RESPONDING

AC VOLT METER

LME49740

www.ti.com

SNAS377B – FEBRUARY 2007 – REVISED APRIL 2013

NOISE MEASUREMENT CIRCUIT

A.

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

power line noise.

Figure 24. Total Gain: 115 dB at f = 1 kHz

RIAA Preamp Voltage Gain,

RIAA Deviation vs Frequency

Flat Amp Voltage Gain vs Frequency

Figure 25.

Figure 26.

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