Texas Instruments ADCx120Q1EVM-PDK, Руководство пользователя

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1 Introduction
The ADCx120Q1EVM-PDK is an evaluation module (EVM) designed to demonstrate the performance and
functionality of the PCMx120-Q1 family of devices. This family includes the devices shown in
Table 1-1 with
differences in performance and function noted. The family also includes the PCMD3140-Q1, which is the digital
mic only version of the device.
Table 1-1. PCMx120-Q1 Family
Device SNR Without DRE (dB) SNR With DRE (dB)
PCM3120-Q1 106 N/A
PCM5120-Q1 108 120
PCM6120-Q1 112 123
PCMD3140-Q1 127 (5th-order PDM) N/A
2 Hardware Overview
The evaluation kit consists of the PCMx120-Q1EVB daughterboard and the AC-MB motherboard. The
motherboard is used to provide power, control, and digital audio signals to the evaluation module. The
daughterboard contains the PCMx120-Q1 device and its input connections.
2.1 AC-MB Settings
2.1.1 Audio Serial Interface Settings
The AC-MB provides the digital audio digital signals to the evaluation module from the universal serial bus
(USB), optical, stereo jack, and external audio serial interface (ASI) header.
Figure 2-1 shows a block diagram of
the ASI routing on the AC-MB.
MUX
USB
Optical Inp ut
Stereo An alog
Input
Exte rnal ASI Hea der
Sou rce
Sele ctor
(SW2)
Aud io
Pro cessor
PCM921 1 Optical Output
To EVM
Figure 2-1. AC-MB Audio Serial Interface Routing
Switch SW2 on the AC-MB selects the audio serial bus that interfaces with the PCMx120 -Q1 EVB. Next to
switch SW2, the AC-MB has a quick reference table to identify the audio serial interface source options and
switch settings. The AC-MB acts as the master for the audio serial interface, with three different modes of
operation: USB, optical or analog, or external ASI.
2.1.1.1 USB
The serial interface clocks and data are provided from the USB interface. The sampling rate and format are
determined by the USB audio class driver on the operating system. The default settings for the USB audio
interface are 32-bit frame size, 48-kHz sampling rate, BCLK and FSYNC ratio is 256, and the format is time-
division multiplexing (TDM).
The AC-MB is detected by the OS as an audio device with the name TI USB Audio UAC2.0 . Figure 2-2
illustrates the AC-MB audio setting for the USB mode of operation.
www.ti.com Introduction
SBAU398 – MARCH 2022
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ADCx120Q1EVM-PDK, PCMD3140Q1EVM-PDK Evaluation Module 3
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