Datasheet

Program Description
3-24
On the bottom of the section, the corresponding FSref frequency is shown
based on the selection of:
1) the Q-value if the PLL has not been enabled, or
2) the P, J, D values if the PLL has been enabled.
3.5.4.3 ADC Section
This section (Audio 1 Tab, Figure 3−10) sets up the audio ADC power and the
analog input source.
By default, the audio ADC has been powered up so that the audio recording
function can start to run with any SW settings. By checking Power Down ADC,
audio ADC power is disabled.
The ADC sample rate can be set as a divider frequency from the reference
frequency, FSref. For example, when FSref = 44.1 kHz (set at the INTERFACE
section of the same tab), an 8-K sample rate is achieved by setting the divider
to 5.5 (44100/5.5 = 8018 Hz).
The audio ADC also has a high-pass filter, which is a submultiple of the sample
rate, to remove dc or low frequency components from the input signal.
The input signal to the audio ADC can be obtained from different analog
resources and under a different mode, selectable from the Select ADC Input
Source option list. The microphone input from the headset or the handset can
be selected; the single-ended or the differential input (paired with AUX1 or
AUX2) can be used.
Also, there is the option to connect the above selected signal or the cell-phone
input to the audio ADC.
3.5.4.4 DAC/Outputs Section
This section sets up the audio DAC power and all functions of the analog
outputs, such as the power, the gain control, and the destination, which
identifies the analog output pin or pins where the analog output signal is sent.
In the Power Down subsection, the DAC and the output driver circuits can be
powered up/down individually. By checking a checkbox, the corresponding
TSC2101 circuit is powered down.
In the SC Protect subsection, the short-circuit (SC) protection function can be
enabled or disabled. When the short-circuit protection functon is enabled and
a short-circuit occurs, all analog outputs are disabled and the corresponding
flag is set. For example, to set the headset SC protection, check the box. In
the event of a headset short circuit, all analog outputs are disabled, and D1 of
control registers in page 2 address 0x1D is set. The TSC2101 requires
hardware or software reset to return to normal operation.
Similar to the ADC, the DAC sample rate can be set as a divider frequency from
the reference FSref frequency, through the DAC Sample Rate option list.
The TSC2101 has the capability to route the stereo DAC output signals to any
of the selected analog output. To route the signals to the headset drivers (SP1