Application Note
AN-1068
Reflow Soldering of MEMS Microphones
INTRODUCTION
This application note provides guidance and suggestions for assembling boards with MEMS microphones. Parameter and profile
details are presented, followed by device footprints, suggested solder paste masks, and PCB land patterns for all InvenSense MEMS
microphones.
PACKAGE INFORMATION
All MEMS microphone models described in this application note are bottom-port devices.
PRINTING PARAMETERS
The printing parameters are:
• Print pressure = 3 kg
• Print speed = 30 mm/sec
• Squeegee type = metal
• Squeegee angle = 60°
SOLDER PASTE STENCIL PARAMETERS
The solder paste stencil parameters are:
• Stencil type = laser cut
• Stencil thickness = 3 mils (~75 µm)
SUGGESTED SOLDER PASTE
The suggested solder paste is Indium8.9 (Type 4—alloy composition—96.5Sn/3.0Ag/0.5Cu (SAC305)). This paste is an air reflow, noclean solder paste specifically formulated to accommodate the higher processing temperatures required by the Sn/Ag/Cu, Sn/Ag, and
other alloy systems favored by the electronics industry to replace conventional Pb-bearing solders.
PLACEMENT FORCE
MEMS microphones can be handled using standard pick-and-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.
• 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.
InvenSense reserves the right to change the detail
specifications as may be required to permit improvements
in the design of its products.
InvenSense Inc.
1745 Technology Drive, San Jose, CA 95110 U.S.A
+1(408) 988–7339
www.invensense.com
Document Number: AN-1068-00
Revision: 1.0
Release Date: 12/31/2013
AN-1068
REFLOW PROFILE
CRITICAL ZONE
TL TO TP
tP
TP
TEMPERATURE
RAMP-UP
TL
tL
TSMAX
TSMIN
tS
RAMP-DOWN
PREHEAT
t25°C TO PEAK TEMPERATURE
TIME
Figure 1. Recommended Soldering Profile Limits
The reflow profile in Figure 1 is recommended for board manufacturing with InvenSense MEMS microphones. These microphones
are also compatible with the J-STD-020 profile.
TABLE 1. RECOMMENDED SOLDERING PROFILE LIMITS
Profile Feature
Sn-Pb
Pb-Free
Average Ramp Rate (TL to TP)
1.25°C/sec max
1.25°C/sec max
Minimum Temperature (TSMIN)
100°C
100°C
Maximum Temperature (TSMAX)
150°C
200°C
Time (TSMIN to TSMAX), tS
60 sec to 75 sec
60 sec to 75 sec
Ramp-Up Rate (TSMAX to TL)
1.25°C/sec
1.25°C/sec
Time Maintained Above Liquidous (tL)
45 sec to 75 sec
~50 sec
183°C
217°C
Peak Temperature (TP)
215°C +3°C/−3°C
260°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 (TP to TL)
3°C/sec max
3°C/sec max
Time 25°C (t25°C) to Peak Temperature
5 minutes max
5 minutes max
Preheat
Liquidous Temperature (TL)
REWORK
The rework process of the MEMS microphone should be carried out using a rework station.
1. Preheat the board to 100°C to 125°C.
2. Place a 6 mm × 6 mm square nozzle over the part.
3. Enable the hot airflow through this nozzle so that the solder becomes liquidous.
4. Use the nozzle to remove the microphone from the substrate.
5. Apply additional solder paste to pad sites using a manually operated dispensing system, such as a syringe with a smallgauge tip.
6. Use a surface-mount placement machine to place the replacement component.
7. Reflow the component on the rework station.
CAUTION
The MEMS microphone package has a port hole opening at the bottom and is sensitive to solder flux. Do not use a vapor phase
soldering process. The MEMS microphone device may be damaged if subjected to cleaning processes. The cleaning solvents may
enter through the port hole and damage the device.
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
Page 2 of 11
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CE-6-1 PACKAGE (ADMP401, ADMP411)
REFERENCE CORNER
2.62
ø0.90 3×
(0.16)
0.10 M C A B
0.05 M C
ø0.25 THRU HOLE
ø1.10
ø1.68
2.54
2.40
ø0.70 2×
1.20
0.10 M C A B
0.05 M C
0.68
0.79
(3.30)
Figure 2. CE-6-1 Device Footprint (Bottom View)
ø0.90 (3×)
2.62
ø1.10
ø1.68
2.54
2.40
1.20
ø0.70 (2×)
0.79
Figure 3. Recommended CE-6-1 PCB Land Pattern
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
Page 3 of 11
1.27
1.27
AN-1068
1.8mm/1.3mm DIA. 0.2032 CUT WIDTH (4×)
0.649mm DIA. (2×)
0.85mm DIA. (3×)
2.4mm
2.54mm
1.2mm
1.27mm
2.62mm
3.41mm
Figure 4. Recommended CE-6-1 Solder Paste Mask
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
Page 4 of 11
AN-1068
CE-5-1 PACKAGE (ADMP421, ADMP521, ADMP522, ADMP621)
3.80
ø0.25 PORT HOLE
REFERENCE CORNER
ø1.70
(0.30)
4× 0.40 × 0.60
0.10 M C A B
0.35
0.05 M C
1.50
0.90
2.80
(0.30)
ø1.10
(0.30)
(1.05)
(0.30)
0.70
2× R0.10
(0.95)
2.05
0.35
Figure 5. CE-5-1 Device Footprint (Bottom View)
3.80
CENTER LINE
(0.30)
ø1.70
0.40 × 0.60 (4×)
0.35
(1.000)
0.90
(0.30)
2.80
ø1.10
(0.30)
(0.30)
0.70
2× R0.10
2.05
(0.550)
0.35
Figure 6. Recommended CE-5-1 PCB Land Pattern
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
Page 5 of 11
AN-1068
2.45
1.498 × 0.248
0.9
0.248 × 0.948 (2×)
0.398 × 0.298 (4×)
1.849
0.35
1.45
CENTER
LINE
0.7
1.000
1.525
1.849
0.248 × 1.148 (2×)
0.375
24°
24°
1.17
0.248 × 0.498 (2×)
1.498
0.205 WIDE
0.362 CUT (3×)
Figure 7. Recommended CE-5-1 Solder Paste Mask
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
Page 6 of 11
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CE-3-2 PACKAGE (ADMP404, ADMP405, ADMP504, ADMP510)
3.35
REFERENCE CORNER
1.52
0.90 × 0.68 2×
1.08
ø1.55
1
0.10 M C A B
0.05 M C
ø0.25 0.00
–0.05
0.035 M
1.22
C
2
(0.54)
2.50
(0.64)
3
ø0.95
(0.75)
0.20 × 45° TYP
PIN NUMBER
Figure 8. CE-3-2 Device Footprint (Bottom View)
1.52
0.68
1.22
0.61
Ø1.55
1.90
Ø0.95
0.61
0.90
Figure 9. Recommended CE-3-2 PCB Land Pattern
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
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NET
1
SIGNAL
2
GND
3
VDD
AN-1068
1.55/1.05 DIA.
0.225 CUT WIDTH (2×)
0.8 × 0.6
2×
1.22
0.2 × 45
TYP
1.52mm
Figure 10. Recommended CE-3-2 Solder Paste Mask
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
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CE-9-1 PACKAGE (ADMP441)
1.07
0.30
1.05 BSC
0.40 × 0.60
(PINS 1 TO 8)
1.56 DIA.
1
2
3
4
0.96 DIA.
0.275
0.250 DIA.
0.225
5
2.66 BSC
1.33 BSC
9
8
7
6
Figure 11. CE-9-1 Device Footprint (Bottom View)
1.05
(6×)
0.25 DIA.
(THRU HOLE)
2.66 (4×)
0.96
1.56
0.40 × 0.60
(8×)
3.16
DIMENSIONS SHOWN IN MILLIMETERS
Figure 12. Recommended CE-9-1 PCB Land Pattern
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
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1.33 (2×)
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1.05
(6×)
0.20
1.05
2.66 (4×)
3.76
1.33 (2×)
1.6
1.07
0.350 × 0.550
(8×)
4.72
DIMENSIONS SHOWN IN MILLIMETERS
Figure 13. Recommended CE-9-1 Solder Paste Mask
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
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AN-1068
Compliance Declaration Disclaimer:
InvenSense believes this compliance information to be correct but cannot guarantee accuracy or completeness. Conformity
documents for the above component constitutes are on file. InvenSense subcontracts manufacturing and the information contained
herein is based on data received from vendors and suppliers, which has not been validated by InvenSense.
Environmental Declaration Disclaimer:
InvenSense believes this environmental information to be correct but cannot guarantee accuracy or completeness. Conformity
documents for the above component constitutes are on file. InvenSense subcontracts manufacturing and the information contained
herein is based on data received from vendors and suppliers, which has not been validated by InvenSense.
This information furnished by InvenSense is believed to be accurate and reliable. However, no responsibility is assumed by
InvenSense for its use, or for any infringements of patents or other rights of third parties that may result from its use. Specifications
are subject to change without notice. InvenSense reserves the right to make changes to this product, including its circuits and
software, in order to improve its design and/or performance, without prior notice. InvenSense makes no warranties, neither
expressed nor implied, regarding the information and specifications contained in this document. InvenSense assumes no
responsibility for any claims or damages arising from information contained in this document, or from the use of products and
services detailed therein. This includes, but is not limited to, claims or damages based on the infringement of patents, copyrights,
mask work and/or other intellectual property rights.
Certain intellectual property owned by InvenSense and described in this document is patent protected. No license is granted by
implication or otherwise under any patent or patent rights of InvenSense. This publication supersedes and replaces all information
previously supplied. Trademarks that are registered trademarks are the property of their respective companies. InvenSense sensors
should not be used or sold in the development, storage, production or utilization of any conventional or mass-destructive weapons
or for any other weapons or life threatening applications, as well as in any other life critical applications such as medical equipment,
transportation, aerospace and nuclear instruments, undersea equipment, power plant equipment, disaster prevention and crime
prevention equipment.
©2013 InvenSense, Inc. All rights reserved. InvenSense, MotionTracking, MotionProcessing, MotionProcessor, MotionFusion,
MotionApps, DMP, and the InvenSense logo are trademarks of InvenSense, Inc. Other company and product names may be
trademarks of the respective companies with which they are associated.
©2013 InvenSense, Inc. All rights reserved.
Document Number: AN-1068-00
Revision: 1.0.
Rev Date: 12/31/13
Page 11 of 11