SLAAE57 June   2022 TAS2563


  1.   Abstract
  2.   Trademarks
  3. 1PDM Microphone
    1. 1.1 PDM Microphone Hardware Connections
    2. 1.2 PDM Input Function Modes
  4. 2Echo Reference
  5. 3SDOUT Data Arrangement
    1. 3.1 Data Slot
    2. 3.2 Data Enable
    3. 3.3 Data Length
  6. 4Practical Configurations Using PPC3
    1. 4.1 Tuning and Audio Processing
  7. 5References

PDM Microphone Hardware Connections

Besides the power supply, the PDM microphone usually needs two signals to work. The two signals are PDM CLK and PDM data. The PDM data can be available at the rising edge or falling edge of PDM CLK. Obtain this data from the PDM Timing Diagram (illustrated in Figure 1-2) in the TAS2563 6.1-W Boosted Class-D Audio Amplifier With Integrated DSP and IV Sense data sheet.

GUID-F4E97B17-AD7D-41CB-8181-45994AA0B7EA-low.gif Figure 1-2 PDM Timing Diagram

The two PDM microphones can be connected together. One PDM microphone works at the CLK raising edge and the other one works at the CLK failing edge. The chipset reads the data both at the raising edge and failing edge but splits them. So, the chipset gets signals of the two PDM microphones.

For example, the PDM microphone has 5 pins, shown in Table 1-1. The SELECT pin can be set high or low to determine which signal edge makes the microphone data available.

Table 1-1 PDM Microphone Connections
Pin # Pin Name Type Description
1 DATA Digital O PDM Output
2 SELECT Digital I

Lo/Hi (L/R) Select

Connect to VDD or GND

3 GROUND Power Ground


CLOCK Digital I Clock Input


VDD Power Power Supply

On the TAS2X63EVM, the two microphones are connected together, but the select pins are set to low or high in different levels. The two microphones work independently in the system.

GUID-20220404-SS0I-WFC8-SBVZ-ZD9SLDPDGBCR-low.gif Figure 1-3 PDM Hardware Connections