AMSCO AS3400

AS3400 AS3410 AS3430
Product Brief
L o w P o w e r A m b i e n t N o i s e - C a n c e l l i n g Spe a k e r D r i v e r
1 General Description
Line Input
volume control via serial interface or volume pin
The AS3400/10/30 are speaker driver with Ambient
Noise Cancelling function for handsets, headphones or
ear pieces. It is intended to improve quality of e.g. music
listening, a phone conversation etc. by reducing background ambient noise.
64 steps @ 0.75dB and MUTE, pop-free gain setting
single ended stereo or mono differential mode
ANC processing
The fully analog implementation allows the lowest power
consumption, lowest system BOM cost and most natural
received voice enhancement otherwise difficult to
achieve with DSP implementations. The device is
designed to be easily applied to existing architectures.
feed-forward cancellation
An internal OTP-ROM can be optionally used to store
the microphones gain calibration settings.
12-30dB noise reduction (headset dependent)
The AS3400/10/30 can be used in different configurations for best trade-off of noise cancellation, required filtering functions and mechanical designs.
The simpler feed-forward topology is used to effectively
reduce low frequency background noise. The feed-back
topology with either 1 or 2 filtering stages can be used to
reduce noise for a larger frequency range, and to even
implement transfer functions like speaker equalization,
Baxandall equalization, high/low shelving filter and to set
a predefined loop bandwidth.
The filter loop is optimized by the user for specific handset electrical and mechanical designs by dimensioning
simple R, C components.
Most handset implementations will make use of a single
noise detecting microphone. Two microphones could be
used to allow for increased flexibility of their location in
the handset mechanical design. Using the bridged mode
allows to even drive high impedance headsets.
feed-back cancellation with filter loop transfer function definable via simple RC components
simple in production SW calibration
10-2000Hz wide frequency active noise attenuation
(headset dependent)
Monitor Function
for assisted hearing, i.e. to monitor announcements
fixed (OTP prog.) ambient sound amplification to
compensate headphone passive attenuation
volume controlled ambient sound amplification
mixed with fixed (OTP prog.) attenuation of LineIn
Incremental Functions
ANC with or without music on the receiving path
improved dynamic range playback
OTP ROM for automatic trimming during production
(4 times programbable)
Performance Parameter
5/3.8mA @ 1.5V stereo/mono ANC; <1uA quiescent
extended PSRR for 217Hz
2 Key Features
Interfaces
2 wire serial control mode & volume inputs
Microphone Input
128 gain steps @0.375dB and MUTE with AGC
differential, low noise microphone amplifier
single ended or differential mode
calibration via Line-In or 2-wire serial interface
single cell or fixed 1.0-1.8V supply with internal CP
Package
improved supply for electret microphone
AS3400, AS3410 QFN24 [4x4mm] 0.5mm pitch
MIC gain OTP programmable
AS3430 QFN32 [5.x5mm] 0.5mm pitch
High Efficiency Headphone Amplifier
2x34mW, 0.1% THD @ 16Ω, 1.5V supply,
100dB SNR
bridged mode for e.g. 300Ω loads
3 Applications
Ear pieces, Headsets, Hands-Free Kits, Mobile Phones,
Voice Communicating Devices
click and pop less start-up and mode switching
www.austriamicrosystems.com
Revision 0.2
1-3
AS3400 AS3410 AS3430 1v0
Product Brief - A p p l i c a t i o n s
Figure 1. AS3410 Feed Forward ANC Block Diagram
Figure 2. AS3430 Feed-Back Block Diagram
www.austriamicrosystems.com
Revision 0.2
2-3
AS3400 AS3410 AS3430 1v0
Product Brief - A p p l i c a t i o n s
Copyrights
Copyright © 1997-2010, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe.
Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner.
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Disclaimer
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in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding
the information set forth herein or regarding the freedom of the described devices from patent infringement. austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice. Therefore,
prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature
range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or lifesustaining equipment are specifically not recommended without additional processing by austriamicrosystems AG for
each application. For shipments of less than 100 parts the manufacturing flow might show deviations from the standard
production flow, such as test flow or test location.
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consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of
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Contact Information
Headquarters
austriamicrosystems AG
A-8141 Schloss Premstaetten, Austria
Tel: +43 (0) 3136 500 0
Fax: +43 (0) 3136 525 01
For Sales Offices, Distributors and Representatives, please visit:
http://www.austriamicrosystems.com/contact
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Revision 0.2
3-3