The TC94B24WBG audio codec from Toshiba Electronics Europe is a
highly integrated single microphone noise cancellation (NC) and echo
cancellation (EC) solution for high-quality voice on smartphones and portable devices.
The TC94B24WBG is claimed to offer design flexibility,
performance, and cost benefits so OEMs can better address challenges
associated with multiple microphone audio processing. Besides processing
the NC/EC algorithms, the high-performance, low-power general-purpose
programmable DSP in the TC94B24WBG allows customers to implement their
own software in the audio codec. This helps differentiate their products
from the competition. Additionally, the highly integrated TC94B24WBG
includes: a 2-channel AECM interface; a 4-channel DECM interface; a
battery-conserving class-G headphone amplifier; ear speaker amplifier;
asynchronous sampling rate converter;
a 4-channel I2S interface; an I2C/SPI interface; and audio post
processing (equalizer, dynamic range controller). It provides all of the
audio inputs and outputs required by mobile and telephony product.
The device interfaces with the audio I/O and the application
processor in smartphones and tablets. The TC94B24WBG comes equipped
with two analogue and four digital microphone inputs to suit various
customers' needs. However, Toshiba’s unique audio processing algorithm
needs just one analogue microphone to efficiently provide NC and EC
simultaneously. Outstanding noise cancellation on the TC94B24WBG is
achieved through a Toshiba proprietary one microphone algorithm. The
algorithm distinguishes voice and noise with statistical noise
estimation while Toshiba’s improved minimum mean square error method in
frequency-domain removes noise only and keeps the voice natural. The
excellent echo cancellation algorithm has a time-domain echo cancelling
adaptive filter and frequency-domain echo suppression. The former
removes linear echo, the later suppresses the rest of non-linear echo.
These two main processes work together closely and intelligently to
achieve high quality echo cancellation by the same microphone used for
the noise cancellation.
Visit Toshiba at www.toshiba-components.com
This article originally appeared on EE Times Europe.