CDB6420 Cirrus Logic Inc, CDB6420 Datasheet - Page 2

• Manufacturer Part Number: CDB6420
• Description: Development Kit
• Manufacturer: Cirrus Logic Inc

Specifications of CDB6420

• Silicon Manufacturer: Cirrus Logic
• Application Sub Type: Speakerphone
• Kit Application Type: Audio / Video / TV
• Silicon Core Number: CS6420
• Kit Contents: Board
• Kit Features: Analog And Digital Patch Area
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

2
Absolute Maximum Ratings ..............................................................................................4
Recommended Operating Conditions..............................................................................4
Power Consumption ..........................................................................................................4
Analog Characteristics ........................................................................................................4
Analog Transmission Characteristics..............................................................................5
Microphone Amplifier ........................................................................................................5
Digital Characteristics .......................................................................................................5
Overview ............................................................................................................................8
Functional Description .....................................................................................................8
Design Considerations ...................................................................................................22
Analog Interface .......................................................................................................8
Microcontroller Interface .........................................................................................10
Clocking ..................................................................................................................19
Power Supply .........................................................................................................20
Algorithmic Considerations .....................................................................................22
Acoustic Interface ..............................................................................................9
Network Interface ............................................................................................10
Description ......................................................................................................10
Register Definitions .........................................................................................11
Reset ...............................................................................................................19
Power Down Mode ..........................................................................................20
Noise and Grounding ......................................................................................21
Full-Duplex Mode ............................................................................................22
Register 0..................................................................................................12
Register 1..................................................................................................14
Register 2..................................................................................................16
Register 3..................................................................................................18
Theory of Operation ..................................................................................22
Adaptive Filter ...........................................................................................23
Update Control ..........................................................................................24
Mic - Microphone Preamplifier Enable ...............................................12
TSD - Transmit Suppression Disable.................................................12
GB - Graded Beta ..............................................................................12
ACC - Acoustic Coefficient Control ....................................................13
RVol - Receive Volume Control .........................................................13
TGain - Transmit Analog Gain ...........................................................13
HD - Half-Duplex Disable...................................................................14
RSD - Receive Suppression Disable .................................................14
Taps - AEC/NEC Tap Allocation ........................................................15
NCC - Network Coefficient Control ....................................................15
TVol - Transmit Volume Control.........................................................15
RGain - Receive Analog Gain............................................................15
NErle - Network ERLE Threshold ......................................................16
NFNse - Network Full-Duplex Noise Threshold .................................16
RHDet - Receive Half-Duplex Detection Threshold ...........................17
HDly - Half-Duplex Holdover Delay....................................................17
NseRmp - Background Noise Power Estimator Ramp Rate..............17
RSThd - Receive Suppression Threshold..........................................17
PCSen- Path Change Sensitivity .......................................................17
AErle - Acoustic ERLE Threshold ......................................................18
AFNse - Acoustic Full-Duplex Noise Threshold.................................18
THDet - Transmit Half-Duplex Detection Threshold ..........................18
TSAtt - Transmit Suppression Attenuation.........................................19
TSBias - Transmit Suppression Bias .................................................19
TSThd - Transmit Suppression Threshold .........................................19
HHold - Hold in Half-Duplex on Howl.................................................19
Pre-Emphasis ....................................................................................23
Graded Beta.......................................................................................23
TABLE OF CONTENTS
CS6420
DS205PP2