W681308DG Datasheet, PDF (36/64 Pages) Nuvotem Talema – W681308 USB Audio Controller from Nuvoton integrates fast 8051 Microcontroller Unit (MCU)

W681308
XXXX PRODUCT DESCRIPTION
12.
PCM Interface , Gain Stage and Mixer
12.1 PCM Interface
The PCM module is a 16-bit parallel/serial data transfer interface. It transfers the 16 bits data from Gain-Stage/Mixer to single
bit Output, and transfers the one bit signal data of Input pin to 16 bits data buffer to the Gain-Stage / Mixer. In normal
operation, the FS and BCLK are generated from the analog PLL module.
PCM Interface specification:
ƒ Master Mode Only
ƒ Support TX / RX path mute
ƒ 8 PCM Bit Clock frequency : 128K, 256K, 512K, 768K, 1M, 1.536M, 2M, 4M Hz.
ƒ 3 frequency selection of the PCM Frame Sync (FS) : 8K, 16K and 48K Hz.
ƒ 16 bit length selection of the PCM Frame Sync (FS) : 1~ 16 bits.
ƒ 4 selection of PCM FS/DATA location + 1 half bit clock delay.
ƒ PCM_FS & PCM_BCLK inverse mode for I2S interface.
12.2 Gain stage
There are 6 programmable gain stages for transmit and receive path. These gain stages are implemented to provide a range
of +24 dB to –31.5 dB with 0.5 dB per step. The Figure 5 is shown the location of these digital gain stages. There are 2 side
tone paths to select from: One before AEC block, one after AEC block. Side tone gain stage is from -0.5dB to -31.5dB with
0.5dB step.
Figure 5 PCM Interface, Gain Stage and Mixer Location
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Rev1.2