Tiny 3.35 mm × 2.50 mm × 0.88 mm surface-mount package
High SNR of 62 dBA
High sensitivity of −38 dBV
Flat frequency response from 200 Hz to 15 kHz
Low current consumption: <250 μA
Single-ended analog output
High PSRR of 70 dB
Compatible with Sn/Pb and Pb-free solder processes
RoHS/WEEE compliant
APPLICATIONS
Smartphones and feature phones
Teleconferencing systems
Digital video cameras
Bluetooth headsets
Video phones
Tab le ts
Bottom Port and Analog Output
ADMP405
GENERAL DESCRIPTION
The ADMP405 is a high quality, high performance, low power,
analog output, bottom-ported omnidirectional MEMS
microphone. The ADMP405 consists of a MEMS microphone
element, an impedance converter, and an output amplifier. The
ADMP405 sensitivity specification makes it an excellent choice
for both near field and far field applications. The ADMP405 has
a high SNR and flat wideband frequency response, resulting in
natural sound with high intelligibility. The specially designed
low frequency cutoff reduces wind noise. Low current
consumption enables long battery life for portable applications.
A built-in particle filter provides high reliability. The ADMP405
complies with the TIA-920 Telecommunications Telephone
Terminal Equipment Transmission Requirements for Wideband
Digital Wireline Telephones standard.
The ADMP405 is available in an ultraminiature 3.35 mm ×
2.50 mm × 0.88 mm surface-mount package. It is reflow solder
compatible with no sensitivity degradation. The ADMP405 is
halide free.
FUNCTIONAL BLOCK DIAGRAM
OUTPUT
AMPLIFIER
ADMP405
Rev. B
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
General Description Section ........................................................ 1
Change to Table 1 .............................................................................. 3
Changes to Table 2 ............................................................................. 4
7/10—Revision 0: Initial Version
Rev. B | Page 2 of 12
Data Sheet ADMP405
SPECIFICATIONS
TA = 25°C, VDD = 1.8 V, unless otherwise noted. All minimum and maximum specifications are guaranteed. Typical specifications are not
guaranteed.
Table 1.
Parameter Symbol Test Conditions/Comments Min Typ Max Unit
PERFORMANCE
Directionality Omni
Sensitivity 1 kHz, 94 dB SPL −41 −38 −35 dBV
Signal-to-Noise Ratio SNR 62 dBA
Equivalent Input Noise EIN 32 dBA SPL
Dynamic Range Derived from EIN and maximum acoustic input 88 dB
Frequency Response1 Low frequency –3 dB point 200 Hz
High frequency –3 dB point 15 kHz
Total Harmonic Distortion THD 105 dB SPL 3 %
Power Supply Rejection Ratio PSRR
Maximum Acoustic Input Peak 120 dB SPL
POWER SUPPLY
Supply Voltage VDD 1.5 3.3 V
Supply Current IS 250 μA
OUTPUT CHARACTERISTICS
Output Impedance Z
Output DC Offset 0.8 V
Output Current Limit 90 μA
1
See and . Figure 4Figure 6
OUT
Deviation limits from flat response within pass
band
217 Hz, 100 mV p-p square wave
superimposed on V
200 Ω
= 1.8 V
DD
−3/+2 dB
70 dB
Rev. B | Page 3 of 12
ADMP405 Data Sheet
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter Rating
Supply Voltage −0.3 V to 3.6 V
Sound Pressure Level (SPL) 160 dB
Mechanical Shock 10,000 g
Vibration
Per MIL-STD-883 Method 2007,
Test Condition B
Temperature Range −40°C to +70°C
T
P
T
L
T
SMAX
RAMP-UP
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ESD CAUTION
t
P
CRITICAL Z O NE
t
L
T
TO T
L
P
T
SMIN
TEMPERATURE
t
S
PREHEAT
t
25°C
TO PEAK
TIME
RAMP-DOWN
09027-002
Figure 2. Recommended Soldering Profile Limits
Table 3. Recommended Soldering Profile Limits
Profile Feature Sn63/Pb37 Pb Free
Average Ramp Rate (TL to TP) 1.25°C/sec max 1.25°C/sec max
Preheat
Minimum Temperature (T
Maximum Temperature (T
Time (T
Ramp-Up Rate (T
SMIN
to T
), tS 60 sec to 75 sec 60 sec to 75 sec
SMAX
to TL) 1.25°C/sec 1.25°C/sec
SMAX
) 100°C 150°C
SMIN
) 150°C 200°C
SMAX
Time Maintained Above Liquidous (tL) 45 sec to 75 sec ~50 sec
Liquidous Temperature (TL) 183°C 217°C
Peak Temperature (TP) 215°C + 3°C/−3°C 245°C + 0°C/−5°C
Time Within 5°C of Actual Peak Temperature (tP) 20 sec to 30 sec 20 sec to 30 sec
Ramp-Down Rate 3°C/sec max 3°C/sec max
Time 25°C (t
) to Peak Temperature 5 minute max 5 minute max
25°C
Rev. B | Page 4 of 12
Data Sheet ADMP405
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
GND
2
ADMP405
TOP VIEW
(TERMINAL SIDE DO WN)
Not to Scale
Figure 3. Pin Configuration
1
OUTPUT
3
V
DD
Table 4. Pin Function Descriptions
Pin No. Mnemonic Description
1 OUTPUT Analog Output Signal.
2 GND Ground.
3 VDD Power Supply.
09027-003
Rev. B | Page 5 of 12
ADMP405 Data Sheet
TYPICAL PERFORMANCE CHARACTERISTICS
10
8
6
4
2
0
–2
SENSITIVITY (dB)
–4
–6
–8
–10
100
FREQUENCY (Hz )
10k1k
09027-004
Figure 4. Frequency Response Mask
0
–10
10
0
(dB)
–10
–20
100
1k10k
FREQUENCY (Hz)
Figure 6. Typical Frequency Response (Measured)
09027-006
–20
–30
–40
PSRR (dB)
–50
–60
–70
–80
10010k
1k
FREQUE NC Y (Hz)
Figure 5. Typical Power Supply Rejection Ratio vs. Frequency
09027-005
Rev. B | Page 6 of 12
Data Sheet ADMP405
APPLICATIONS INFORMATION
CONNECTING TO ANALOG DEVICES, INC., AUDIO
CODECS
The ADMP405 output can be connected to a dedicated codec
microphone input (see Figure 7) or to a high input impedance
gain stage (see Figure 8). A 0.1 μF ceramic capacitor placed close
to the ADMP405 supply pin is used for testing and is recommended to adequately decouple the microphone from noise on
the power supply. A dc-blocking capacitor is required at the
output of the microphone.
0.1µF
V
DD
ADMP405
OUTPUT
GND
2.2µF
MINIMUM
Figure 7. ADMP405 Connected to the Analog Devices ADAU1761 or
ADAU1361 Codec
MICBIAS
ADAU1761
OR
ADAU1361
LINN
LINP
CM
9027-020
GAIN = (R1 + R2)/R1
V
DD
ADMP405
OUTPUT
GND
0.1µF
MINIMUM
1µF
V
REF
10kΩ
R1R2
V
REF
OP177
V
OUT
09027-021
Figure 8. ADMP405 Connected to the OP177 Op Amp
SUPPORTING DOCUMENTS
Evaluation Board User Guide
UG-143, EVAL-ADMP405Z-FLEX: Bottom-Ported Analog
Output MEMS Microphone Evaluation Board
Application Notes
AN-1003, Recommendations for Mounting and Connecting
Analog Devices, Inc., Bottom-Ported MEMS Microphones
AN-1068, Reflow Soldering of the MEMS Microphone
AN-1112, Microphone Specifications Explained
AN-1124, Recommendations for Sealing Analog Devices, Inc.,
Bottom-Port MEMS Microphones from Dust and Liquid
Ingress
Rev. B | Page 7 of 12
ADMP405 Data Sheet
PCB LAND PATTERN LAYOUT
The recommended PCB land pattern for the ADMP405 should
be laid out to a 1:1 ratio to the solder pads on the microphone
package, as shown in Figure 9. Care should be taken to avoid
applying solder paste to the sound hole in the PCB. A suggested
0.68
solder paste stencil pattern layout is shown in Figure 10. The
diameter of the sound hole in the PCB should be larger than the
diameter of the sound port of the microphone. A minimum
diameter of 0.5 mm is recommended.
The MEMS microphone can be handled using standard pickand-place and chip shooting equipment. Care should be taken
to avoid damage to the MEMS microphone structure as follows:
•Use a standard pickup tool to handle the microphone.
Because the microphone hole is on the bottom of the
package, the pickup tool can make contact with any part
of the lid surface.
•Use care during pick-and-place to ensure that no high
shock events above 10 kg are experienced because such
events may cause damage to the microphone.
•Do not pick up the microphone with a vacuum tool that
makes contact with the bottom side of the microphone.
Do not pull air out of or blow air into the microphone port.
•Do not use excessive force to place the microphone on
the PCB.
REFLOW SOLDER
For best results, the soldering profile should be in accordance
with the recommendations of the manufacturer of the solder
paste used to attach the MEMS microphone to the PCB. It is
recommended that the solder reflow profile not exceed the limit
conditions specified in Figure 2 and Ta bl e 3 .
BOARD WASH
When washing the PCB, ensure that water does not make
contact with the microphone port. Blow-off procedures and
ultrasonic cleaning must not be used.
Rev. B | Page 9 of 12
ADMP405 Data Sheet
RELIABILITY SPECIFICATIONS
The microphone sensitivity after stress must deviate by no more than ±3 dB from the initial value.
Table 5.
Stress Test Description
Low Temperature Operating Life −40°C, 500 hours, powered
High Temperature Operating Life +125°C, 500 hours, powered
Temperature Humidity Bias (THB) +65°C/85% relative humidity (RH), 500 hours, powered
Temperature Cycle −40°C/+125°C, one cycle per hour, 100 cycles
High Temperature Storage +150°C, 500 hours
Low Temperature Storage −40°C, 500 hours
Component Charge Device Model (CDM) ESD All pins, 0.5 kV
Component Human Body Model (HBM) ESD All pins, 1.5 kV
Component Machine Model (MM) ESD All pins, 0.2 kV
Rev. B | Page 10 of 12
Data Sheet ADMP405
OUTLINE DIMENSIONS
0.98
0.88
0.78
3.06 REF
P
N
I
1
TOP VIEW
3.425
3.350
3.275
2.21
REF
0.65 REF
R
E
C
O
2.575
2.500
2.425
E
N
C
E
E
F
R
E
R
R
N
1.22 BSC
0.64 REF
.
0
0.30 BSC
0
9
.
0
N
P
(
I
T
0
2
×
0.75 REF
8
6
.
0
×
)
S
3
,
1
0.54
REF
P
Y
°
5
4
1.52
1
3
BOTTOM VIEW
1.08
0.30
BSC
2
0.25 NOM
0.20 MIN
1.56 DIA.
0.95 DIA.
1.25
DIA.
THRU HOLE
(SOUND PORT)
SIDE VIEW
Figure 11. 3-Terminal Chip Array Small Outline No Lead Cavity [LGA_CAV]