CS43L22-CNZ Cirrus Logic Inc, CS43L22-CNZ Datasheet - Page 62

• Manufacturer Part Number: CS43L22-CNZ
• Description: IC DAC W/HDPN & SPKR AMPS 40QFN
• Manufacturer: Cirrus Logic Inc

Specifications of CS43L22-CNZ

• Package / Case: 40-QFN
• Number Of Bits: 24
• Data Interface: Serial
• Number Of Converters: 1
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Conversion Rate: 96 KSPS
• Resolution: 24 bit
• Interface Type: Serial
• Operating Supply Voltage: 1.8 V or 2.5 V
• Operating Temperature Range: + 85 C
• Mounting Style: SMD/SMT
• Number Of Dac Outputs: 2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 598-1529 - BOARD EVAL FOR CS43L22
• Power Dissipation (max): -
• Settling Time: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 598-1650

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10.PCB LAYOUT CONSIDERATIONS
10.1
10.2
Power Supply, Grounding
As with any high-resolution converter, the CS43L22 requires careful attention to power supply and ground-
ing arrangements if its potential performance is to be realized.
power arrangements, with VA and VHP connected to clean supplies VD, which powers the digital circuitry,
may be run from the system logic supply. Alternatively, VD may be powered from the analog supply via a
ferrite bead. In this case, no additional devices should be powered from VD.
Extensive use of power and ground planes, ground plane fill in unused areas and surface mount decoupling
capacitors are recommended. Decoupling capacitors should be as close to the pins of the CS43L22 as pos-
sible. The low value ceramic capacitor should be closest to the pin and should be mounted on the same
side of the board as the CS43L22 to minimize inductance effects.
All signals, especially clocks, should be kept away from the FILT+ and VQ pins in order to avoid unwanted
coupling into the modulators. The VQ decoupling capacitors, particularly the 0.1 µF, must be positioned to
minimize the electrical path from AGND. The CDB43L22 evaluation board demonstrates the optimum layout
and power supply arrangements.
QFN Thermal Pad
The CS43L22 is available in a compact QFN package. The underside of the QFN package reveals a large
metal pad that serves as a thermal relief to provide for maximum heat dissipation. This pad must mate with
an equally dimensioned copper pad on the PCB and must be electrically connected to ground. A series of
vias should be used to connect this copper pad to one or more larger ground planes on other PCB layers.
In split ground systems, it is recommended that this thermal pad be connected to AGND for best perfor-
mance. The CS43L22 evaluation board demonstrates the optimum thermal pad and via configuration.
Confidential Draft
3/4/10
Figure 1 on page 9
shows the recommended
CS43L22
DS792F2