XE3005 ETC, XE3005 Datasheet - Page 4

• Manufacturer Part Number: XE3005
• Description: (XE3005 / XE3006) Low-Power Audio CODEC
• Manufacturer: ETC

2 Functional Description
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 Device Functions
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.
4
ADC Signal Channel
MIC-Amplifier
CODEC
Figure 2: typical usage of CODEC
ADC
Digital wireless transmission – Bluetooth™
Voice recognition / speech synthesis
Serial Audio Interface
DSP / Microcontroller
DAC
Power Amplifier
SPI
Data Sheet
XE3005/XE3006
D0212-116