JAJSNO1 December 2023 TAC5112
ADVANCE INFORMATION
The device has an independent programmable channel gain setting for each output channel that can be set to the appropriate value based on the maximum input signal expected in the system, This can be done by configuring OUT1x_LVL_CTRL and OUT2x_LVL_CTRL bits. Coarse gain configuration from -6dB to +24dB is available with these controls in steps of 6dB. .
The device has a programmable digital volume control with a range from –100 dB to 27 dB in steps of 0.5 dB with the option to mute the channel recording. The digital volume control value can be changed dynamically while the DAC channel is powered-up and playing. During volume control changes, the soft ramp-up or ramp-down volume feature is used internally to avoid any audible artifacts. Soft-stepping can be entirely disabled using the DAC_DSP_DISABLE_SOFT_STEP (P0_R115_D1) register bit.
The digital volume control setting is independently available for each of the 4 single-ended output channels. In the case of 2 Channel Differential DAC, Only settings for DAC_CH1A and DAC_CH2A are applicable. The device also supports an option to gang up the volume control setting for all channels together using the channel 1 A digital volume control setting, regardless if channel 1A is powered up or powered down. This gang-up can be enabled using the DAC_DSP_DVOL_GANG (P0_R115_D0) register bit.
Table 7-27 shows the programmable options available for the digital volume control.
P0_R103_D[7:0] : DAC_CH1A_DVOL[7:0] | DVC SETTING FOR OUTPUT CHANNEL 1A |
---|---|
0000 0000 = 0d | Output channel 1 DVC is set to mute |
0000 0001 = 1d | Output channel 1 DVC is set to –100 dB |
0000 0010 = 2d | Output channel 1 DVC is set to –99.5 dB |
0000 0011 = 3d | Output channel 1 DVC is set to –99 dB |
… | … |
1100 1000 = 200d | Output channel 1 DVC is set to –0.5 dB |
1100 1001 = 201d (default) | Output channel 1 DVC is set to 0 dB |
1100 1010 = 202d | Output channel 1 DVC is set to 0.5 dB |
… | … |
1111 1101 = 253d | Output channel 1 DVC is set to 26 dB |
1111 1110 = 254d | Output channel 1 DVC is set to 26.5 dB |
1111 1111 = 255d | Output channel 1 DVC is set to 27 dB |
Similarly, the digital volume control setting for output channels 1B,2A, and 2B can be configured using the CH1B_DVOL (P0_R103) to CH2B_DVOL (P0_R112) register bits, respectively.
The internal digital processing engine soft ramps up the volume from a muted level to the programmed volume level when the channel is powered up, and the internal digital processing engine soft ramps down the volume from a programmed volume to mute when the channel is powered down. This soft-stepping of volume is done to prevent abruptly powering up and powering down the playback channel which can cause audible artifacts. This feature can also be entirely disabled using the DAC_DSP_DISABLE_SOFT_STEP (P0_R115_D1) register bit.