http://www.www.datasheet4u.com

900,000+ Datasheet PDF Search and Download

Datasheet4U offers most rated semiconductors datasheets pdf





Cirrus Logic
Cirrus Logic

CS6420 Datasheet Preview

CS6420 Datasheet

Full-Duplex Speakerphone Chip

No Preview Available !

CS6420 pdf
CS6420
Full-Duplex Speakerphone Chip
Features
l Single-chip full-duplex hands-free operation
l Automatic gain control
l Optional 34 dB microphone preamplifier
l Integrated mute and volume control
l Integrated 80 dB IDR dual codec
l Speech-trained Network and Acoustic Echo
Cancellers
l Powerdown mode
l Microcontroller Interface
General Description
Most modern speakerphones use half-duplex operation,
which switches transmission between the far-end talker
and the speakerphone user. This is done because the
acoustic coupling between the speaker and microphone
is much higher in speakerphones than in handsets
where the coupling is mechanically suppressed.
The CS6420 enables full-duplex conversation with a sin-
gle-chip solution. The CS6420 can easily replace
existing half-duplex speakerphone ICs with a huge in-
crease in conversation quality.
The CS6420 consists of telephone & audio interfaces,
two codecs and an echo-cancelling DSP.
ORDERING INFORMATION
CS6420-CS
CDB6420
20-pin SOIC
Evaluation Board
DGND
NC4 NC3 NC2
NC1
AGND
AVDD
NI
0,6,9.5,12 dB
Pre-Emphasis
Filter
+Σ
-
Network
Echo Canceller
Acoustic
Echo Canceller
Pre-Emphasis
Filter
AO
Clock
Generation
CLKI
CLKO
NO
DVDD
-
Σ+
Microcontroller Interface
DATA STROBE DRDY
RST
1 k
34 dB
0,6,9.5,12 dB
2.12 V
BANDGAP
3.5 V
AVDD
APO
MB
API
Preliminary Product Information
Cirrus Logic, Inc.
Crystal Semiconductor Products Division
P.O. Box 17847, Austin, Texas 78760
(512) 445 7222 FAX: (512) 445 7581
http://www.crystal.com
This document contains information for a new product.
Cirrus Logic reserves the right to modify this product without notice.
Copyright © Cirrus Logic, Inc. 1997
(All Rights Reserved)
JUN ‘97
DS205PP2
1



Cirrus Logic
Cirrus Logic

CS6420 Datasheet Preview

CS6420 Datasheet

Full-Duplex Speakerphone Chip

No Preview Available !

CS6420 pdf
CS6420
TABLE OF CONTENTS
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
Analog Interface .......................................................................................................8
Acoustic Interface ..............................................................................................9
Network Interface ............................................................................................10
Microcontroller Interface .........................................................................................10
Description ......................................................................................................10
Register Definitions .........................................................................................11
Register 0..................................................................................................12
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
Register 1..................................................................................................14
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
Register 2..................................................................................................16
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
Register 3..................................................................................................18
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
Reset ...............................................................................................................19
Clocking ..................................................................................................................19
Power Supply .........................................................................................................20
Power Down Mode ..........................................................................................20
Noise and Grounding ......................................................................................21
Design Considerations ...................................................................................................22
Algorithmic Considerations .....................................................................................22
Full-Duplex Mode ............................................................................................22
Theory of Operation ..................................................................................22
Adaptive Filter ...........................................................................................23
Pre-Emphasis ....................................................................................23
Graded Beta.......................................................................................23
Update Control ..........................................................................................24
2 DS205PP2


Part Number CS6420
Description Full-Duplex Speakerphone Chip
Manufacturer Cirrus Logic
Total Page 30 Pages
PDF Download
CS6420 pdf
CS6420 Datasheet PDF
[partsNo] view html
View PDF for Mobile








Similar Datasheet

1 CS6420 Full-Duplex Speakerphone Chip Cirrus Logic
Cirrus Logic
CS6420 pdf
2 CS6422 Enhanced Full-Duplex Speakerphone IC Cirrus Logic
Cirrus Logic
CS6422 pdf





Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z

site map

webmaste! click here

contact us

Buy Components

Privacy Policy