Cirrus Logic CDB5346 - Manual (Page 3)

DS861DB1 3
CDB5346
1. SYSTEM OVERVIEW
The CDB5346 evaluation board is an excellent means for evaluating the CS5346 ADC. Analog and digital audio
signal interfaces are provided, a simple bus architecture is used for easily configuring the evaluation platform,
and a USB cable is included for use with the Windows
®
configuration software available for download from
www.cirrus.com .
The CDB5346 schematic set is shown in Figures 4 through 8 . Though the CS5346 device is compatible with the
CS5345 device the CDB5346 platform was not designed to accommodate the CS5345. For CS5345 comparisons
please use the CDB5345.
1.1 Power
Power must be supplied to the evaluation board through the red +5.0 V binding post. An on-board regulator
provides 3.3 V. Appropriate supply levels for powering VA, VD, VLS, and VLC are set by a series of jumpers
(
see Table 2 on page 9 ). All voltage inputs must be referenced to the single black binding post ground con-
nector ( see Table 1 on page 9 ).
WARNING: Please refer to the CS5346 data sheet for allowable voltage levels.
1.2 Grounding and Power Supply Decoupling
The CS5346 requires careful attention to power supply and grounding arrangements to optimize perfor-
mance.
Figure 3 on page 10 provides an overview of the connections to the CS5346. Figure 9 on page 16
shows the component placement. Figure 10 on page 17 shows the top layout. Figure 11 on page 18 shows
the bottom layout. The decoupling capacitors are located as close to the CS5346 as possible. Attention has
been paid to maximize the ground plane fill on the evaluation board. The series resistors on the analog in-
puts have been placed close to the CS5346 device in order to reduce any unwanted coupling from long trac-
es with high source impedance.
1.3 CS5346 Audio ADC
A complete description of the CS5346 is included in the CS5346 product data sheet.
The required configuration settings of the CS5346 are made in its control port registers, accessible through
the CS5346 tab of the Cirrus Logic FlexGUI software.
Clock and data source selections are made through the microcontroller. Basic routing selections can be
made using the CS5346 Controls tab in the GUI software application. Advanced options are accessible
through the Board Configuration sub-tab on the Register Maps tab of the Cirrus Logic FlexGUI software.
1.4 CS8406 Digital Audio Transmitter
A complete description of the CS8406 transmitter ( Figure 7 on page 14 ) and a discussion of the digital audio
interface are included in the CS8406 data sheet.
The CS8406 converts the PCM data generated by the CS5346 to the standard S/PDIF data stream. The
CS8406 can operate in either master or slave mode, accepts 128 Fs, 256 Fs, 384 Fs, and 512 Fs master
clocks on the OMCK input pin, and can operate in the Left-Justified, I²S, Right-Justified 16-bit, and Right-
Justified 24-bit interface formats.
The most common operations of the CS8406 may be controlled via the CDB5346 Controls tab in the GUI
software application. Advanced options are accessible through the CS8406 sub-tab on the Register Maps
tab of the Cirrus Logic FlexGUI software.