CDB42L55 Cirrus Logic Inc, CDB42L55 Datasheet - Page 25

• Manufacturer Part Number: CDB42L55
• Description: Eval Bd Ultra Low Power Stereo Codec
• Manufacturer: Cirrus Logic Inc

Specifications of CDB42L55

• Main Purpose: Audio, CODEC
• Embedded: Yes, FPGA / CPLD
• Utilized Ic / Part: CS42L55
• Primary Attributes: 2 Stereo Analog Inputs, Stereo Line and Headphone Outputs, S/PDIF Transmitter and Receiver
• Secondary Attributes: GUI, USB, RS232, I2C Interfaces, USB or External or Battery Power Supply
• Product: Audio Modules
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 598-1506; CDB-42L55

DS773F1
4.3
Analog In to Analog Out Passthrough
The CS42L55 accommodates analog routing of the analog input signal directly to the headphone and line
out amplifiers. This feature is useful in applications that utilize an FM tuner where audio recovered over-the-
air must be transmitted to the headphone amplifier without digital conversion in the ADC and DAC. This an-
alog passthrough path reduces power consumption and is immune to modulator switching noise that could
interfere with some tuners. This path is selected using the Line and/or HP mux bits and powering down the
ADC.
Referenced Control
PDN_ADCx .........................
HPxMUX..............................
LINExMUX...........................
Referenced Control
PGAxVOL[5:0] .....................
ADCxATT[7:0] ......................
MAX[2:0], MIN[2:0] ..............
below full scale
Input (before ALC)
below full scale
MIN[2:0]
MIN[2:0]
Response
(after ALC)
Output
ALC
Register Location
“Power Down ADC x” on page 42
“Headphone Input Select” on page 47
“Line Input Select” on page 47
Register Location
“PGAx Volume” on page 49
“ADCx Volume” on page 50
“ALC Threshold (Address 26h)” on page 64
PGA Gain and/or
Attenuator
Figure 11. ALC Operation
RRATE[5:0]
ARATE[5:0
]
MAX[2:0]
below full scale
MAX[2:0]
below full scale
CS42L55
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