Sanyo EP92H - Manual (Page 13)

SANYO is developing a chip that can support phone conversations
with just an earphone.
Conversation is possible without taking off your earphones.
● STFD (single transduce full duplex) technology makes a separate microphone unnecessary!
Increased flexibility in end product design
● Phone conversions are possible even in crowds or noisy environments
Since the sound is picked up directly in the ear, wind and other sounds can be reduced.
● Better audio quality than bone conduction microphones
Since an even clearer voice sound is possible, it is easy to identify the speaker.
● New applications in various other wireless markets
Phone conversations are possible without removing one’s earphones when listening to music.
Bone conduction
microphones
Wind sounds
Earphone mic
There are also
new applications
Hands free
Noise is reduced
Higher audio
quality
Resistant to noise
2005 2006 2007
STDF evaluation board
Integration
Lower power consumption
Higher functionality
First generation
Evaluation board verification
STFD function confirmation For portable equipment
For wireless equipment
Second generation
For business equipment
For PC peripherals
For portable accessories
Functions
• STFD
• Volume
Added functionality
• Noise canceler
• Speach speed conversion
• Hands free
Diaphragm
Tympanic
Tympanic
Simultaneous transmission and
reception at a single diaphragm
Vibrations in the air
Vibrations in the air
The headphone diaphragm
catches the weak audio
signal emitted from
the tympanic
Signal conversion using a DSP.
Signal transmission while maintaining clarity.
Vocalization
To the
circuit
Transmission
Reception
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Developing a chip that can support phone conversations with just an earphone.
Earphone Mic Solutions
What is an earphone mic?
Development roadmap
Single Transducer Full Duplex
S.T.F.D.
Under development