80-0206-R Datasheet, PDF (28/49 Pages) List of Unclassifed Manufacturers – Speech Recognition Processor

RSC-4128
Digital Transfer Functions
Data Sheet
Lowpass response
Detail of passband
Frequency
Below 8 kHz
9.395 kHz
20 kHz
Above 20 kHz
Attenuation
Min
Max
0
1.18
3 dB
87.82
53
NOTE: A 1uF capacitor should be connected to AMPCOM and tied to GND, a 2.2uF should be connected to VCM
and tied to GND, and a 0.1uF capacitor should be connected to VREF and tied to GND. Failure to connect this
capacitors will substantially degrade ADC performance, and FluentChip™ technology.
A/D Conversion
The amplified signal is processed by a delta-sigma A/D converter that provides a 1-bit over-sampled digital signal.
This digital stream is filtered and decimated to produce 16-bit samples at the fixed rate of 18,636 samples per
second. The 16 bit signal will have about 12.5 bits of dynamic range, with about 10 bits above the noise level.
These samples are then provided to the RSC-4128 digital filter unit formatted as signed two’s-complement 16-bit
values. The samples are stored in the digital filter input registers “adcSampleHi” (register F5) and “adcSampleLo”
(register F4).
Note: Using the AFE for general purposes other than as intended in FluentChip™ technology modules may conflict
with FluentChip™. Such conflicts may adversely impact FluentChip™ functionality and/or the functionality of the
general purpose application. Care should be taken to avoid such conflicts. Contact Sensory Technical Support for
help in this area.
Audio Wakeup
The Audio Wakeup unit is an analog/digital circuit that can be configured to wakeup from one of four specific audio
events:
1) Two handclaps, or any two sharp, closely spaced sounds
2) Three handclaps, or any three sharp, closely spaced sounds
3) A whistle
4) Any “loud” sound above a specified amplitude, with duration options of 1 or 2 seconds
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P/N 80-0206-R
© 2006 Sensory Inc.