SLASF32A December 2023 – October 2024 TAD5142
PRODUCTION DATA
Digital audio data flows between the host processor and the TAD5142 on the digital audio serial interface (ASI), or audio bus. This bus can be operated in target or controller mode through pin control. The ASI supports TDM, I2S and Left-Justified bus protocols. The data is in MSB-first, two's-complement pulse code modulation (PCM) format, with pin-selectable word-length configuration.
The device supports an audio bus controller or target mode of operation using the hardware pin MD0. In target mode, FSYNC and BCLK work as input pins whereas in controller mode, FSYNC and BCLK work as output pins generated by the device. Table 6-2 shows the controller and target mode selection using the MD0 pin.
MD0 | CONTROLLER AND TARGET SELECTION |
---|---|
Short to Ground | Target I2S Mode |
Short to Ground with 4.7K Ohms | Target TDM Mode |
Short to AVDD | Controller I2S Mode |
Short to AVDD with 4.7K Ohms | Controller TDM Mode |
Short to AVDD with 22K Ohms | Target LJ Mode |
MD2 | MD1 | WORD LENGTH, SUPPLY MODE, AND INTERPOLATION FILTER SELECTION (Valid for Target Mode only) |
---|---|---|
Low | Low | AVDD=3.3V, Word Length=32, Linear-phase Filter |
Low | High | AVDD=1.8V, Word Length=32, Linear-phase Filter |
High | Low | AVDD=3.3V, Word Length=24, Linear-phase Filter |
High | High | AVDD=3.3V, Word Length=32, Low-latency phase Filter |
The TAD5142 also offers daisy chain option for TDM mode of operation. This option is auto enabled whenever device is selected to be in TDM Mode with MD0. MD6 Pin acts as a Daisy Chain output in this mode. In this case, for a TDM with N slots, the device plays the audio present on the last 2 slots, and the remaining slots are shifted to the right and sent on the MD6 pin, as shown in the block diagram in the Figure 6-2.