Ears-free, thus providing extended use comfort and safety No electromagnetic waves (EMW)

Bone Conduction Transducer

A. General Description

Most of what we hear is due to sound waves traveling through the air. Sound waves travel

through the outer and middle ear before arriving at the cochlea in the inner ear. Sound waves can

also get to the cochlea through direct vibration of the bones in the head.

Bone conduction is the conduction of sound to the inner ear through the bones of the skull.

Bone conduction products have following advantages over traditional headphones:

1Ears-free, thus providing extended use comfort and safety

2No electromagnetic waves (EMW), eliminating the potential effect of EMW on cerebrum (if

any)

3High sound clarity in very noisy environments, can be used with hearing protection

4Can have the perception of stereo sound

Bone conduction Transducers (BCT) is an electro-mechanical device, which directly convert

the electric signal to mechanical vibration. BCT can be used for sound generator for mobile device

such as MP3, headphone, Bluetooth, mobile phone and table vibration speakers.

The BCT transducer is the new world standard in mobile device for sound generation. . It

delivers accurate broadband sound output to the users. . Prepare to discover a new dimension of

sound. The BCT transducer creates sound through vibration transfer instead of pressuring the air

around you. The audio signal is delivered so cleanly that the brain interprets the stimulus as

Sound.

B. Physical Dimension

Figure 1. Bone conduction transducer for mobile device,

Figure 2. Physical layout of the transducer and physical dimension in (mm)

Figure 3. Schematic diagram of the space requirement for installing a bone conduction transducer

on the mobile device. Physical dimension in (mm).

For installing BCT in the mobile device, such as cellular phone, the space with 12.5 mm of

length, 6.5mm of width and 4.5 mm of height in the mobile phone is required, as shown in Figure 3.

The distance between two 1.5 mm screws is 6 mm. It is necessary to insert a foam or a rub sheet

between transducer and shell of mobile device for eliminating shell vibration.

C. . Specifications

1 Model Number : NDR-080504 Unit

2 Resonant Frequency : 16 +/- 0.5 kHz

3 Operating Voltage (Max) : 12 Vpp

4 Average working voltage : 3.7 V

5 Sound Pressure Level (Min) : 88 at 1kHz dB

6 Current Consumption (Max) : 600 mA

7 Average Working current : 100 mA

8 Impedance : 8±5% Ohm

9 Frequency : 300-19000 Hz

10 Rated input(W) : 0.8 W

11 Maximum input(W) : 1.5 W

12 Operating Temperature : -20 to +60 °C

13 Storage Temperature : -30 to +70 °C

14 Operating humanity (Max) : 95 %

C. Characteristic

Figure 4 Frequency response spectrum of the transducer

D. Applications

1) Bluetooth Ear plug

2) Cellular Phone

3) Headphone

4) Hearing aids

5) Table vibration speakers

E).SIZE  12.5*6.5*4.5

Bone Conduction Transducer