Cirrus Logic CDB4344 - Manual (Page 4)

CDB4344
4 DS613DB2
5. GROUNDING AND POWER SUPPLY DECOUPLING
As with any high performance converter, the CS4344 requires careful attention to power supply
and grounding arrangements to optimize performance. Figure 2 details the connections to the
CS4344 and Figures 6, 7, and 8 show the component placement and top and bottom layout. The
decoupling capacitors are located as close to the CS4344 as possible. Extensive use of ground
plane fill in the evaluation board yields large reductions in radiated noise.
6. ANALOG OUTPUT FILTERING
The analog output on the CDB4344 has been designed according to the CS4344 datasheet. This
output circuit includes an AC coupling cap and a single pole R and C. An additional load resis-
tance may be added by stuffing R10 and R26 to test the CS4344’s load driving capability.
Table 1. System Connections
CONNECTOR INPUT/OUTPUT SIGNAL PRESENT
+5V Input + 5 V power
GND Input Ground connection from power supply
+3.3V to +5V Input +3.3 V to +5 V positive supply for the CS4344 VA power
S/PDIF INPUT - J5 Input Digital audio interface input via coax
S/PDIF INPUT - OPT1 Input Digital audio interface input via optical
PCM INPUT - J9 Input Input for master, serial, left/right clocks and serial data
LEFT_OUT and
RIGHT_OUT
Output RCA line level analog outputs