BU-23842-000 Knowles Acoustics, BU-23842-000 Datasheet - Page 27
![ACCELEROMETER 1.5VDC SOLDER](/photos/38/54/385447/bu-23842_sml.jpg)
BU-23842-000
Manufacturer Part Number
BU-23842-000
Description
ACCELEROMETER 1.5VDC SOLDER
Manufacturer
Knowles Acoustics
Series
BUr
Specifications of BU-23842-000
Sensitivity
-40dB ±4dB
Mounting Type
Surface Mount
Package / Case
Module
Dimensions
7.87 mm L x 5.54 mm W x 2.24 mm D
Depth
2.24 mm
Length
7.87 mm
Width
5.54 mm
Input Current
50µA
Supply Voltage
1.5V
Sensor Mounting
SMD
Frequency Response Min
300Hz
Frequency Response Max
3kHz
Transducer Function
Vibration
Rohs Compliant
Yes
Axis
-
Acceleration Range
-
Voltage - Supply
-
Output Type
-
Bandwidth
-
Interface
-
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
Other names
BU-23842
BU-23842
Q2807356
BU-23842
Q2807356
MICROPHONE AND SPEAKER BASICS
SPEAKERS
The speaker converts an electrical signal into sound. A cross section of a typical Knowles speaker is shown in Fig. 3.
The basic components of the speaker are: a coil of wire, a metal U-shaped reed called the armature, a pair of permanent
magnets, a drive rod, and a diaphragm.
The coil and armature act as an electromagnet. An alternating current in the coil causes the polarity of the armature to
switch back and forth from north to south. The free end of the armature bends slightly up and down as it is attracted
alternately to the top and bottom magnets (Fig. 4). The diaphragm, pulled along by the drive rod, pumps air in and out of
the speaker. The mechanical motion of the armature is thus converted into sound.
The sound output of a typical Knowles’ speaker is measured in units of dB SPL (sound pressure level) relative to 20 µPa.
Fig. 3: Cross section of a Knowles EH speaker
DIAPHRAGM
DRIVE ROD
OUTPUT TERMINAL
COIL
MAGNETS
ARMATURE
Fig. 4: The motor of the speaker has a coil, an armature, and a pair of permanent magnets.
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27
Note: All performance curves are typical