CDB4344

DS613DB2

3

CDB4344 SYSTEM OVERVIEW

The CDB4344 evaluation board is an excellent means of quickly evaluating the CS4344. The

CS8416 digital audio interface receiver provides an easy interface to digital audio signal sources

including the majority of digital audio test equipment. The evaluation board also allows the user

to supply external PCM clocks and data through a header for system development.

The CDB4344 schematic has been partitioned into 4 schematics shown in Figures 2 through 5.

Each partitioned schematic is represented in the system diagram shown in Figure 1. Notice that

the system diagram also includes the interconnections between the partitioned schematics.

1. CS4344 DIGITAL TO ANALOG CONVERTER

A description of the CS4344 is included in the CS4344 datasheet.

2. CS8416 DIGITAL AUDIO RECEIVER

The system receives and decodes the standard S/PDIF data format using a CS8416 Digital Au-

dio Receiver, Figure 3. The outputs of the CS8416 include a serial bit clock, serial data, left-right

with R42 and R47). The operation of the CS8416 and a discussion of the digital audio interface

is included in the CS8416 datasheet.

The evaluation board has been designed such that the input can be either optical or coax, see

Figure 3. However, both inputs cannot be driven simultaneously.

The right hand switch of S2 sets the output MCLK to LRCK ratio of the CS8416. This switch

should be set to 256 (closed) for inputs Fs<=96 kHz and 128 (open) for Fs>=64 kHz. The 8416

must be manually reset using RX_RST (S1) when this switch is changed.

3. INPUT FOR CLOCKS AND DATA

The evaluation board has been designed to allow interfacing to external systems via the header

J9. Header J9 allows the evaluation board to accept externally generated PCM clocks and data.

The schematic for the clock/data input is shown in Figure 4. The left hand switch of S2 selects

the source as either CS8416 (closed) or header J9 (open).

Please see the CS4344 datasheet for more information.

4. POWER SUPPLY CIRCUITRY

Power is supplied to the evaluation board by three binding posts (GND, +5V, and ‘+3.3V to +5V’),

see Figure 5. The ‘+3.3V to +5V’ which supplies VA can be jumpered to a +3.3 V regulator or the

+5V binding post. The VA supply should be set to the recommended values stated in the CS4344

datasheet.

WARNING: Refer to the CS4344 datasheet for maximum allowable voltages levels. Operation

outside of this range can cause permanent damage to the device.