Electronic Components Datasheet Search |
|
AS3421-EQFP-500 Datasheet(PDF) 1 Page - ams AG |
|
AS3421-EQFP-500 Datasheet(HTML) 1 Page - ams AG |
1 / 61 page A S 3 4 2 1 A S 3 4 2 2 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 S p e a k e r D r i v e r www.austriamicrosystems.com Revision 0.90 1 - 61 D a t a s h e e t 1 General Description The AS3421/22 are speaker driver with Ambient Noise Cancelling function for headsets, headphones or ear pieces. It is intended to improve quality of e.g. music listening, a phone conversation etc. by reducing background ambient noise. 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. An internal OTP-ROM can be optionally used to store the microphone gain calibration settings as well as all application specific settings. The AS3421/22 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 frequencies typically up to 2-3kHz. The feed-back topology with either 1 or 2 filtering stages has it strengths especially at very low frequencies. The typical bandwidth for feedback system is from 20Hz up to 1kHz which is a little bit lower than with feed forward systems. The filter loop for both systems is determined by measurements, for each specific headset individually, and depends very much on mechanical designs. The gain and phase compensation filter network is implemented with cheap resistors and capacitors for lowest system costs. AS3421/22 features also an audio playback only mode which allows the user to easily switch between ANC on and off mode. In ANC off mode unused blocks are automatically switch off to guaranty lowest power consumption in each operating mode. 2 Key Features Microphone Input 128 gain steps @ 0.375dB and MUTE with AGC Differential, low noise microphone amplifier Single ended or differential mode Improved supply for electret microphone MIC gain OTP programmable High Efficiency Headphone Amplifier 2x23mW, 0.1% THD+N @ 32 Ω, 1.5V supply, 100dB SNR Bridged mode for e.g. 300 Ω loads Click and pop less start-up and mode switching Line Input Volume control via serial interface or push buttons 64 steps @ 0.75dB and MUTE, pop-free gain setting Fully differential stereo line inputs ANC processing Feed-forward cancellation Feed-back cancellation with filter loop transfer function definable via simple RC components Simple in production SW calibration 12-30dB noise reduction (headset dependent) 10-3000Hz 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 Incremental Functions ANC with or without music on the receiving path Music Playback mode for lowest power consumption OTP ROM for automatic trimming during production (4 times programmable) Performance Parameter 7mA @ 1.5V stereo ANC; <1 A quiescent Extended PSRR for 217Hz Increased TDMA noise immunity Interfaces 2-wire serial control mode & volume inputs Calibration via Line-In or 2-wire serial interface Fixed 1.0-1.8V supply with internal CP Package AS3421 QFN24 [4x4mm] 0.5mm pitch AS3422 QFN32 [5x5mm] 0.5mm pitch 3 Applications The devices are ideal for wireless devices like stereo Bluetooth headsets as well as stereo wireless headsets. |
Similar Part No. - AS3421-EQFP-500 |
|
Similar Description - AS3421-EQFP-500 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |