SLASF38A December 2023 – March 2025 TAD5212-Q1
PRODUCTION DATA
In addition to the gain calibration, the phase delay in each record channel can be finely calibrated or adjusted in steps of one modulator clock cycle for a cycle range of 1 to 63 for the phase error. The modulator clock for the digital microphones is the clock set by PDM_CLK, and is 3.072MHz (the output data sample rate is multiples or submultiples of 48kHz) or 2.8224MHz (the output data sample rate is multiples or submultiples of 44.1kHz) in default configurations. User can configure the PDM_CLK using the PDM_CLK_CFG[1:0] (P0_R53_D[7:6]) register bits. The programmable channel phase calibration feature is very useful for many applications that must match the phase with fine resolution between each channel, including any phase mismatch across channels resulting from external components or microphones. Table 6-43 shows the available programmable options for channel phase calibration when operating with default modulator clocks.
| P0_R84_D[7:2] : ADC_CH1_PCAL[5:0] | CHANNEL PHASE CALIBRATION SETTINGS FOR INPUT CHANNEL 1 |
|---|---|
| 00 0000 = 0d (default) | No phase calibration |
| 00 0001 = 1d | Phase calibration delay is set to one cycle of the modulator clock |
| … | … |
| 11 1111 = 63d | Phase calibration delay is set to 63 cycles of the modulator clock |
Similarly, the channel phase calibration setting for input channel 2 to channel 4 can be configured using the ADC_CH2_PCAL (P0_R89_D[7:2]) to ADC_CH4_PCAL (P0_R97_D[7:2]) register bits, respectively.