Cirrus Logic CDB35L00-X4 - Manual (Page 4)

4 DS913DB2
CDB35L00-X4
1.3.1.1 Hybrid Control Resistor Configuration
Each CS35L00 device has a hybrid control resistor. When
the hybrid control resistor for each CS35L00 is populated,
it connects the LFILT+ pin to VBATT and enables the
Standard Class-D functionality (SD or FSD modes) for the
corresponding device. When the hybrid control resistor
for each CS35L00 is not populated, LFILT+ is floating,
and the Hybrid Class-D functionality (HD or FHD modes)
is enabled.
The hybrid control resistors (R13, R23, R33, R43) are lo-
cated on the bottom side of the board adjacent to the
LFILT+ decoupling capacitor and are highlighted in blue
in
Figure 1 .
A combination of the hybrid control resistors and the S1
MODE switch allow the CS35L00 devices (U1-U4) on the
CDB35L00-X4 board to be configured in all 4 of the oper-
ational modes. There is no requirement to have the all
four of the CS35L00 devices configured in the same
mode. Each device can be configured to the user’s re-
quirements.
Table 2 lists the configuration options avail-
able using the hybrid control resistors and the S1 MODE
switch.
Table 2. Hybrid Control Resistor & S1 Switch MODE Configurations
1.4 Shutdown Control
The S1 switch implements shutdown control for the four CS35L00 devices on the CDB35L00-X4. SD1-2
controls the shutdown for U1 and U2. SD3-4 controls the shutdown for U3 and U4 as shown in
Table 3 and
on the schematic in Figure 4 on page 9 .
S1 MODE Switch:
GND VBATT
Hy
brid Control
Re
sistor
R13: VBATT U1 = FSD U1 = SD
R13: Removed U1 = FHD U1 = HD
R23: VBATT U2 = FSD U2 = SD
R23: Removed U2 = FHD U2 = HD
R33: VBATT U3 = FSD U3 = SD
R33: Removed U3 = FHD U3 = HD
R43: VBATT U4 = FSD U4 = SD
R43: Removed U4 = FHD U4 = HD
Figure 1. Hybrid Control Resistors