AM79C03JC AMD (ADVANCED MICRO DEVICES), AM79C03JC Datasheet - Page 15

• Manufacturer Part Number: AM79C03JC
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of AM79C03JC

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Discrimination against 12 kHz and 16 kHz
Metering Signals
If the DSLAC device is used in a metering application
where 12 kHz or 16 kHz tone bursts are injected onto the
telephone line toward the subscriber, a portion of those
tones also may appear at the V
band signals may cause frequency components to ap-
pear below 4 kHz at the digital output. For a 12 kHz tone,
the frequency components below 4 kHz are reduced
from the input by at least 48 dB, and for 16 kHz tones,
the components are reduced by more than 70 dB.
To avoid degradation of in-band transmission perfor-
mance, the input levels of these out-of-band tones
must be limited. The maximum allowable level is 100
mVrms at 12 kHz, and is 500 mVrms at 16 kHz. An
external notch filter at the VIN pin of the DSLAC device,
incorporated with the metering injection design, is ef-
fective in reducing these tone levels.
Level (dBm0)
–10
–40
–20
–30
–50
0
IN
terminal. These out-of-
3.4
Figure 6. Spurious Out-of-Band Signals
4.0
Frequency (kHz)
SLAC Products
4.6
DSLAC Device Specification
–28 dB
Spurious Out-of-Band Signals at the
Analog Output
With PCM code words representing a sine wave signal
in the range of 300 Hz to 3400 Hz at a level of 0 dBm0
applied to the digital input, the level of the spurious out-
of-band signals at the analog output is less than the
limits shown in the following table.
With code words representing any sine wave signal in
the range 3.4 kHz to 4.0 kHz at a level of 0 dBm0 applied
to the digital input, the level of the signals at the analog
output are below the limits in Figure 6. The amplitude
of the spurious out-of-band signals between 3400 Hz
and 4600 Hz is given by the formula:
40 kHz to 240 kHz
240 kHz to 1 MHz
4.6 kHz to 40 kHz
Frequency
A
=
–32 dB
–
14
–
14
sin
09875H-010
--------------------------- - dBm0
f 4000
1200
–
–32 dBm0
–46 dBm0
–36 dBm0
Level
15