AM79D2251JC AMD [Advanced Micro Devices], AM79D2251JC Datasheet - Page 19

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

Transmit and Receive Paths
In this section, the transmit path is defined as the analog input to the ISLAC device (VINn) to the
PCM voice output of the ISLAC A-law/µ law speech compressor (See Figure 7-1 in the Am79R2xx/
Am79D2251x Technical Reference). The receive path is defined as the PCM voice input to the
ISLAC speech expander to the analog output of the ISLAC device (VOUTn). All limits defined in this
section are tested with B = 0, Z = 0 and X = R = RG = 1.
When RG is enabled, a 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 relative levels (dBm0) are used in any of the following transmission characteristics, the
specification holds for any setting of (AX + GX) gain from 0 to 12 dB or (AR + GR) from 0 to –12 dB.
These transmission characteristics are valid for 0 to 70°C.
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