CDK-5571 Cirrus Logic Inc, CDK-5571 Datasheet - Page 7

• Manufacturer Part Number: CDK-5571
• Description: Audio Modules & Development Tools KIT CDB558 w/ Capture Plus II
• Manufacturer: Cirrus Logic Inc

Specifications of CDK-5571

• Product: Audio Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The analog inputs are designed for connections to single-ended input signals referenced to ground. The
usable input voltage range is -2.048 V to +2.048 V. The theoretical input frequency range of the CS5571
is from DC to the Nyquist frequency of 50 kHz. The analog input buffer amplifiers are configured for a cut-
off frequency of 16.8 kHz to band-limit noise into the ADC. Changing the cutoff frequency will change the
noise bandwidth accordingly.
3.3.2
Analog input channel selection is controlled through the multiplexer. The multiplexer is configured with a
pull-down resistor on the MUX control line to enable input channel labeled "INPUT A" by default. To select
channel B, apply 3.3 V to the multiplexer input control line (MUX).
Signal levels for controlling the multiplexer that selects between analog input channels A and B is shown
in Table 3.
During multiplexing, the maximum sample rate for each channel is half that of the ADC’s maximum sam-
ple rate. Additionally, the Nyquist frequency for each channel is half of the ADC’s Nyquist frequency.
3.3.3
The CS5571 ADC makes use of an externally generated power-on reset. Therefore, after power is ap-
plied to the ADC, the reset pin must be driven low then released. Pressing the Reset button generates a
reset cycle. A reset cycle can be generated at any time during ADC operation. The ADC RST pin (active
low) is held inactive through a pull-up resistor.
3.3.4
The voltage reference IC provided generates a 4.096 V precision reference.
3.3.5
The reference frequency for the CS5571 ADC is provided by a 16.000 MHz oscillator.
DS768DB4
Multiplexer
ADC Reset
Voltage Reference
ADC Reference Frequency
Control Input (MUX)
Table 3. Analog Input Channel Selection
Multiplexer
3.3 V
0 V
Input Channel
Enabled
A
B
CDB5571
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