The recommended power-up sequence is to apply VCC first, followed by VREF, and then the clock signal. This ensures that the internal voltage regulators and analog circuits are properly initialized.
To minimize noise and distortion, it's essential to separate the analog and digital grounds, keep the analog signal traces away from the digital clock and data lines, and use a solid ground plane. Additionally, decoupling capacitors should be placed close to the power pins, and the VREF pin should be bypassed to analog ground with a 10nF capacitor.
The PCM1702P can support clock frequencies up to 256x the sampling frequency. However, the maximum clock frequency is limited by the specific application and the quality of the clock signal. In general, a clock frequency of 128x or 192x the sampling frequency is recommended for optimal performance.
In master clock mode, the PCM1702P generates the clock signal internally, and the MCLK pin is an output. In slave clock mode, the PCM1702P receives the clock signal from an external source, and the MCLK pin is an input. The mode is selected by the state of the MCLK pin during power-up. If MCLK is high during power-up, the PCM1702P operates in master clock mode. If MCLK is low during power-up, the PCM1702P operates in slave clock mode.
The digital output pins of the PCM1702P should be terminated with a 10kΩ to 20kΩ pull-up resistor to VCC, and a 100Ω to 200Ω series resistor to limit the current and prevent damage to the output drivers.
PCM1702P datasheet
by Texas Instruments
