DS687DB2

7

CDB5343

Changing the state of this switch while the device is running will have no effect on the CS5343 as it must

be reset to detect the change. Reset is accomplished by removing and restoring power to the device. Al-

ternatively, removing and restoring MCLK will initiate a reset of the digital section, which is also sufficient

for the CS5343 to detect a change in mode settings.

9.2.2

CS8406

This switch sets the CS8406 for either Master Mode or Slave Mode. In Master Mode, the CS5343 must

be configured as a clock slave and “SCLK, LRCK” set to “TO HDR.” In Slave Mode, either the CS5343

can be set to Master Mode or the user can set the “SCLK, LRCK” switch to “FROM HDR.”

9.2.3

MCLK

MCLK can either come from the header, as selected by “FROM HDR,” or from the on-board crystal oscil-

lator (Y1) as selected by “TO HDR.”

9.2.4

SCLK, LRCK

The sub-clocks, SCLK and LRCK, are either produced on board by the CS5343 or the CS8406 or pro-

duced externally. If generated by an external device, this switch must be set to “FROM HDR.” If the

CS5343 or CS8406 generate the sub-clocks, this switch must be set to “FROM HDR.”

9.2.5

SPEED

The CS5343 can operate in Single-Speed Mode (SSM) or Double-Speed Mode (DSM) as described in

the CS5343 product datasheet.

In Master Mode, the CS5343 defaults to SSM based on an internal 100 k

Ω pull-up resistor from the LRCK

pin to VA. Setting the “SPEED” switch to “DSM” will place a 10 k

Ω pull-down resistor between LRCK and

GND to select Double-Speed Mode. Because the CS5343 determines its Master Mode speed based on

start-up options, the speed mode cannot be toggled during operation. To change the speed in Master

Mode, the device must be reset by removing and restoring power or removing and restoring MCLK.

This switch also configures the MCLK/LRCK ratio for the CS8406. Selecting SSM configures the CS8406

for a 512x MCLK/LRCK ratio while DSM sets an MCLK/LRCK ratio of 256x. In this design, the CS8406

cannot support of a 384x MCLK/LRCK ratio.

9.2.6

MCLK/LRCK Ratio

This switch will configure the CS5343 for either a 256x MCLK/LRCK ratio or a 384x MCLK/LRCK ratio in

Master Mode. In Slave Mode the CS5343 auto-detects the MCLK/LRCK ratio; therefore this configuration

step is unnecessary in Slave Mode. In Master Mode, selection of this parameter is performed via a start-

up option. An internal 100 k

Ω pull-up resistor from the SCLK pin to VA will select 256x by default. An ex-

ternal 10 k

Ω pull-down resistor from the SCLK pin to GND will select an MCLK/LRCK ratio of 384x.

Typical applications that use a 384x MCLK/LRCK ratio derive a 48 kHz LRCK from a 18.384 MHz MCLK.

Deriving MCLK from the included 12.288 MHz crystal oscillator will result in a sample rate of 32 kHz.

The CS8406 is not configured to support a 384x MCLK/LRCK ratio in this design; therefore analysis in

this mode must be performed by retrieving data through the interface header (J3).