ia3222 integration, ia3222 Datasheet - Page 41

• Manufacturer Part Number: ia3222
• Description: Ia3222/ia3223 Ez Daa? Chipset With Analog Interface
• Manufacturer: integration

IA3222/IA3223
cancelled residual is seen as noise. Trans-hybrid drift mostly arises from thermal effects due to heating of the Line Side both from
the line current and the electronic environment. The IA3222 was designed to have very low thermal drift to minimize these effects.
In telephony applications, hybrid return loss is heard as “sidetone”. Some sidetone is desirable as long as it is not excessive in
volume. The IA3222 hybrid network, like most telephones, provides a good compromise sidetone over most normal loaded and non-
loaded lines without requiring other compensation networks.
Better trans-hybrid balance against any line can be achieved by adding a suitable analog or digital transform between the
transmitted audio and the received signal summing node. This can be done in the analog domain with RC networks, some type of
receiver summing node (either resistive or using an op amp) and some type of transmitter inversion.
Similarly, different termination impedances can by synthesized either in the analog or digital domain by complex transformation of
the receiver signal back into the transmitter input. In some digital DAAs, the sampling delay prevents this except for very low
frequencies. But since the IA3222/3223 uses eight-times oversampling, line to Rx pin and Tx pin to line delays are significantly less,
thus making impedance synthesis possible.
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