BL-21785-000 Knowles Acoustics, BL-21785-000 Datasheet - Page 22
![MIC ELEMENT PIEZO INSTRUMENT](/photos/0/4/490/bl-21785_sml.jpg)
BL-21785-000
Manufacturer Part Number
BL-21785-000
Description
MIC ELEMENT PIEZO INSTRUMENT
Manufacturer
Knowles Acoustics
Series
BLr
Type
Piezo Condenserr
Specifications of BL-21785-000
Sensitivity
-69dB ±3dB
Voltage - Rated
1.3V
Current
160µA
Size / Dimension
Rectangular - 7.87mm L x 5.54mm W x 2.24mm H
Impedance
4K Ohm
Frequency
20Hz ~ 10kHz
Termination
Solder Pads
Direction
Omnidirectional
Port Location
Side
Directional Properties
Omnidirectional
Operating Voltage
3 V
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
Transducer Function
Microphone
Device Type
Microphone
Directivity
Omni
External Diameter
1.41mm
Output Impedance
4000ohm
Drain Current Max
160µA
Outer Diameter
1.41mm
Rohs Compliant
Yes
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Filter Type
-
S/n Ratio
-
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
Other names
423-1003
BL-1785
BL-21785
BL1785
BL-1785
BL-21785
BL1785
22
SPECIALTY TRANSDUCERS – Speakers
SR SERIES
At 8.8mm diameter, the SR is the first round balanced armature speaker in the
marketplace. SR offers output equivalent to the BK series and maximizes
bass performance.
CI SERIES
Knowles’ largest and most powerful speaker, the CI series is the speaker of choice.
With its high efficiency and a 143dB SPL maximum output, the CI speaker provides
optimal low frequency performance.
Note: All performance curves are typical
M M o o d d e e l l
SR-8850NSS-000
SR-8850NWS-000
M M o o d d e e l l
CI-22748-000
CI-22762-000
CI-22955-000
CI-22960-000
CI-28487-000
CI-28597-000
– Balanced Armature Speaker 9.47 x 7.18 x 4.10 (mm)
– Balanced Armature Speaker 8.84 DIA x 5.00 (mm)
Sensitivity @ 1kHz
Sensitivity @ 1kHz
(dB SPL)
(dB SPL)
114.5
113
125
125
125
125
125
125
•
•
•
•
•
•
Round package facilitates earphone designs
Drop-in upgrade for moving coil dynamic speakers
Designed for high volume production
Balanced armature technology
Two-terminal zero-bias and three-terminal
center-tapped configurations
Various port locations, coil impedances,
termination configurations, and frequency
responses available
Port Location
Port Location
Face
Face
12C
12C
12C
11S
1S
1S
www.knowles.com
Impedance @ 500Hz
Impedance @ 500Hz
100 @ 1kHz
68 @ 1kHz
68 @ 1kHz
(Ohms)
(Ohms)
21.5
250
175
400
37
Max SPL @ 500Hz
Max SPL @ 500Hz
(dB SPL)
(dB SPL)
124.5
128.5
128.5
128.5
128.5
128.5
128.5
123
135
125
115
105
130
125
120
115
110
105
100
95
95
90
85
80
100
100
Max SPL @ 1st Peak
Max SPL @ 1st Peak
(dB SPL)
(dB SPL)
2
2
130.5
138.5
138.5
138.5
138.5
138.5
138.5
132
3
3
4
4
5
5 6 7 8 9
6 7 8 9
FREQUENCY (Hz)
FREQUENCY (Hz)
1k
1k
2
2
3
3
4
4
5
5
6 7 8 9
6 7 8 9
10k
10k