Cirrus Logic CRD42L52 - Manual (Page 8)

8 DS680RD1
CRD42L52
Table 2 shows expected performance characteristics when the boards are configured to make analog input
to digital output measurements.
3.3 S/PDIF In to Speaker Out
Stereo differential speaker outputs from the CS42L52 can be monitored on screw terminals J3 and J4. The
CS42L52 can be set up to provide data to the PWM modulator for producing speaker outputs from either
the serial port PCM input or the ADC output using the FlexGUI software. For a description of the Cirrus
FlexGUI software controls, refer to
Section 4 on page 9 . Table 3 shows expected performance characteris-
tics when the boards are configured to make speaker output measurements.
Figure 3. CRD42L52 and CDB42LDB1 Block Diagram for Digital Loopback Testing
3.4 Analog In to Analog Out - Digital Loopback
In order to use the CS42L52 in digital loopback mode, one can configure the CS42L52 to operate in master
or slave mode.
Figure 3 shows the board configuration when the CODEC is set up to operate in master
mode. In this mode, the CS42L52 receives an MCLK from the driver board from the CS8416 S/PDIF reciev-
er. As described in
Section 1.3 on page 4 and shown in Figure 3 , the S/PDIF receiver uses the on-board
12.288 MHz clock as an MCLK when it is not receiving a S/PDIF input stream. Table 3 shows expected per-
formance characteristics when the boards are configured to make speaker output measurements.
Plot Location
Dynamic Range - Line In to S/PDIF Out Figure 9 on page 15
Frequency Response - Line In to S/PDIF Out Figure 10 on page 15
THD + N - Line In to S/PDIF Out Figure 11 on page 15
Table 2. Line In to S/PDIF Out Performance Plots
Plot Location
Frequency Response - S/PDIF In to Speaker Out Figure 17 on page 16
Table 3. S/PDIF In to Speaker Out Performance Plots
Plot Location
Dynamic Range - Line In to HP Out (Digital Loopback) Figure 18 on page 16
THD + N - Line In to HP Out (Digital Loopback) Figure 19 on page 17
CS42L52
CS8416
S/PDIF Rx
MCLK
LRCLK
SCLK
SDOUT
AIN1A
AIN1B
R
T
Line
Input
(MASTER)
(MASTER)
12.288 MHz
Oscillator
T
R
Headphone
Output
HP/ LINE_OUTA
HP/ LINE_OUTB
CRD42L52
RMCK