AM79D2251JC AMD [Advanced Micro Devices], AM79D2251JC Datasheet - Page 24

• Manufacturer Part Number: AM79D2251JC
• Description: Dual Intelligent Subscriber Line Audio-Processing Circuit (ISLAC)
• Manufacturer: AMD [Advanced Micro Devices]

Discrimination against Out-of-Band Input Signals
When an out-of-band sine wave signal with frequency and level A is applied to the analog input, there may be
frequency components below 4 kHz at the digital output which are caused by the out-of-band signal. These
components are at least the specified dB level below the level of a signal at the same output originating from a
1014 Hz sine wave signal with a level of A dBm0 also applied to the analog input. The minimum specifications are
shown in the following table.
24
16.6 Hz < f < 45 Hz
45 Hz < f < 65 Hz
65 Hz < f < 100 Hz
3400 Hz < f < 4600 Hz
4600 Hz < f < 100 kHz
Frequency of Out-of-Band Signal
Level (dB)
–10
–20
–30
–40
–50
0
Figure 12. Discrimination Against Out-of-Band Signals
Note:
The attenuation of the waveform below amplitude A between
3400 Hz and 4600 Hz is given by the formula:
Attenuation (db)
3.4
–25 dBm0 < A
–25 dBm0 < A
–25 dBm0 < A
–25 dBm0 < A
–25 dBm0 < A
Amplitude of Out-of-Band Signal
=
14
4.0
Am79D2251
–
Frequency (kHz)
14
sin
0 dBm0
0 dBm0
0 dBm0
0 dBm0
0 dBm0
------------------------- -
4000 f
1200
4.6
–28 dBm
–
–32 dB, –25 dBm0 < input < 0 dBm0
ISLAC Device Specification
Level below A
see Figure 12
18 dB
25 dB
10 dB
32 dB
19256A-012