AM79212JC AMD (ADVANCED MICRO DEVICES), AM79212JC Datasheet - Page 24

• Manufacturer Part Number: AM79212JC
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of AM79212JC

• Lead Free Status / RoHS Status: Supplier Unconfirmed

The transmit path is defined as the section between the analog input to the ASLAC device (VIN) and the GCI voice
output of the ASLAC device A-law/µ-law speech compressor (see the Voice Transmission Path figure in the Technical
Reference). The receive path is defined as the section between the GCI voice input to the ASLAC device speech
expander and the analog output of the ASLAC device (VOUT). All limits defined in this section are tested with B =
0, Z = 0, and X = R = RG = 1.
When RG is enabled, a nominal gain of –6.02 dB is added to the digital section of the receive path.
When AR is enabled, a nominal gain of –6.02 dB is added to the analog section of the receive path.
When AX is enabled, a nominal gain of +6.02 dB is added to the analog section of the transmit path.
When the gains in the transmit path are set to AX = 0 dB and GX = 0 dB, a 1014 Hz sine wave with a nominal
voltage of 0.596 V rms for µ-law and 0.6 V rms for A-law at the ASLAC device analog input will correspond to a level
of 0 dBm0 at the GCI voice output. Under these conditions, the overload level of the transmit path is 1.25 V peak
referenced to VREF.
When the gains in the receive path are set to AR = GR = 0 dB, a 1014 Hz sine wave with a level of 0 dBm0 at the
GCI voice input will correspond to a nominal voltage of 0.596 V rms for µ-law and 0.6 V rms for A-law at the analog
output of the ASLAC device. Under these conditions, the maximum receive output level is 1.25 V peak referenced to
VREF.
When relative levels (dBm0) are used in any of the following transmission characteristics, the specification holds for
any setting of (AX + GX) gain from 0 dB to 12 dB or (AR + GR + RG) from 0 to –12 dB.
These transmission characteristics are valid for 0°C to 70°C and for VCC = +5 V ± 0.25 V.
Attenuation Distortion
The attenuation of the signal in either path is nominally independent of the frequency. The deviations from nominal
attenuation will stay within the limits shown in Figure 1. The reference frequency is 1014 Hz and the signal level is –
10 dBm0. Minimum transmit attenuation at 60 Hz is 24 dB.
24
Attenuation (dB)
Figure 1. Transmit and Receive Path Attenuation vs. Frequency
–0.125
0.125
0.6
2
1
0
0
200
300
Am79212/Am79C202 Data Sheet
Receive path
P R E L I M I N A R Y
600
ASLAC Device Specification
Frequency (Hz)
3000
3200
3400
0.80
0.65
0.2