SLAAEE0 November   2023 TAC5111 , TAC5112 , TAC5211 , TAC5212 , TAC5412-Q1 , TAD5112 , TAD5212 , TAD5212-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Output Configuration
    1. 2.1 Common-mode Generation
    2. 2.2 Output Load Range for Line Output And Headphone
    3. 2.3 Mixing and Bypass
  6. 3Summary
  7. 4References

Common-mode Generation

The TAD5212 features Pseudo diff with external Common Mode sense to get rid of crosstalk on the output common mode. For this, HPL and HPR pins are referenced to HPCOM Common Mode with HPCOM_FB as star connection that results in reduction of channel to channel crosstalk.

There are two different methods to generate the internal common-mode. One method is to use the supply voltage as the reference and generate a common-mode voltage, which is typically half of the VDD, as shown in Figure3a. While this method is a straight-forward approach, this common-mode voltage carries the unwanted frequency components present in the supply voltage, showing up at the output. The second method to generate common-mode voltage is to use the internal reference, such as VREF, and generate the common-mode voltage from the reference voltage, providing a better power supply rejection ratio for single-ended configuration. This second method is shown in Figure 2-8.

GUID-20231107-SS0I-BXPD-DZPV-LDWLMBDNBFP4-low.svg Figure 2-8 Internal Generation of VCM Using Supply Voltage or Reference Voltage