xe3006 Semtech Corporation, xe3006 Datasheet - Page 5

• Manufacturer Part Number: xe3006
• Description: Sandman? Codec | Semtech
• Manufacturer: Semtech Corporation

2
A CODEC is typically used for voice and audio applications as an interface between a Digital Signal processor (DSP) or
microcontroller and the analogue interfaces like a microphone and loudspeaker.
This chapter provides a brief description of the CODEC features relating to the CODEC configuration. The configuration
of the CODEC is defined by programming registers through a serial interface. A detailed description of the registers
defining details of the CODEC setup can be found in chapter 3 and 7. Digital voice and audio samples are passed
through the Serial Audio Interface.
2.1
2.1.1
The ADC channel is a chain of programmable amplifier, band-pass filter, sigma-delta modulator and a decimation filter.
The amplifier gain is programmable to 5x (default) and 20x. The band-pass filter has cut-off frequencies proportional to
the sampling rate. The sigma-delta modulator operates at a frequency of 64 times the sampling rate. The analog
modulator is followed by a digital decimation filter. The digital output data (16 bits, 2’s complement format) is made
available through the Serial Audio Interface. The format of the Serial Audio interface can be selected through register J.
With the default register settings the ADC can run at a sampling frequency up to 20 kHz. When used with a sampling
frequency higher than 20 kHz, then register C has to be changed.
The whole ADC chain can be powered-down through register I.
© Semtech 2005
FUNCTIONAL DESCRIPTION
DEVICE FUNCTIONS
ADC Signal Channel
MIC-Amplifier
CODEC
Figure 3: Typical usage of CODEC
ADC
Digital wireless transmission – Bluetooth™
Voice recognition / speech synthesis
Serial Audio Interface
DSP / Microcontroller
5
DAC
Power Amplifier
SPI
XE3005/XE3006
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