Am79D2251

23

Total Distortion Including Quantizing Distortion

The signal to total distortion ratio will exceed the limits shown in Figure 10 for either path when the

input signal is a sine wave signal of frequency 1014 Hz.

Figure 10. Total Distortion with Tone Input, Both Paths

Overload Compression

Figure 11 shows the acceptable region of operation for input signal levels above the reference input

power (0 dBm0). The conditions for this figure are:

(1) 1 dB < GX

≤ +12 dB; (2) –12 dB ≤ GR < –1 dB; (3) Digital voice output connected to digital voice

input; and (4) measurement analog to analog.

Figure 11. A/A Overload Compression

Input Level (dBm0)

Signal-to-Total

Distortion (dB)

Dual ISLAC Specification

0

-30

-40

-45

A

A-Law

µ-Law

A

35.5dB

35.5dB

B

35.5dB

35.5dB

C

30dB

31dB

D

25dB

27dB

B

C

D

Fundamental

Output Power

(dBm0)

Fundamental Input Power (dBm0)

1

2

3

4

5

6

7

8

9

123

4

5

6

78

9

Region

2.6

Acceptable