DA7218 Datasheet, PDF (161/173 Pages) Dialog Semiconductor – Ultra-Low Power Stereo Codec

DA7218
Ultra-Low Power Stereo Codec
Appendix A Applications Information
A.1 Codec Initialization
Depending on the specific application, some general settings need to be set. Examples of these
settings include the sample rate, the PLL, and the DAI. Then the amplifiers, the mixers and channels
of the ADC/DAC have to be configured and enabled via their respective control registers.
An example sequence is shown below:
1. Configure clock mode as required for operation, (for example PLL or PLL bypass).
2. Configure the DAI.
3. Configure the charge pump if the headphone path is in use.
4. Set input and output mixer paths and gains.
5. Enable input and output paths using the Level 2 System Controller (SLC2).
A.2 Automatic Level Control Calibration
When using the automatic level control (ALC or AGS) in sync-mode the DC offset between the digital
and analog PGAs must be cancelled. This is performed automatically if the following procedure is
performed:
1. Enable microphone amplifiers unmuted.
2. Mute microphones.
3. Enable input mixer and ADC unmuted.
4. Enable AIF interface.
5. Set calib_auto_en in CALIB_CTRL to ‘1’ (CALIB_CTRL = 0x44). This bit will auto-clear when
calibration is complete.
6. When calibration is complete, enable the ALC with alc_sync_mode (ALC_CTRL1 = 0x30) and
calib_offset_en (CALIB_CTRL = 0x44).
7. Unmute microphones.
Datasheet
CFR0011-120-00
Revision 2.5
161 of 173
01 Sep 2016
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