WOLFSON WM7210IMSE/RV

WM7210, WM7210E
w
Top Port Digital Silicon Microphone
DESCRIPTION
FEATURES
The WM7210 is a low-profile silicon digital microphone. It
offers high Signal to Noise Ratio (SNR) and low power
consumption and is suited to a wide variety of consumer
applications.

The WM7210 incorporates Wolfson’s proprietary
CMOS/MEMS membrane technology, offering high
reliability and high performance in a miniature, low-profile
package. The WM7210 is designed to withstand the high
temperatures associated with automated flow solder
assembly processes. (Note that conventional microphones
can be damaged by this process.)
The WM7210 incorporates a high performance ADC,
which outputs a single-bit Pulse Density Modulated (PDM)
audio data stream. The WM7210 supports selectable
left/right channel assignment for a two-channel digital
microphone interface, enabling efficient connection of
multiple microphones in stereo/array configurations.
The WM7210E variant offers a tighter tolerance on the
microphone sensitivity, giving reduced variation between
parts. This removes the need for in-line production
calibration of part-to-part microphone variations.

High SNR; selectable sensitivity tolerance options
WM7210 – SNR 58dB, Sensitivity +/-3dB
WM7210E – SNR 58dB, Sensitivity +/-1dB
Low power
-
Sleep mode - 2μA
Normal operation - 650μA


Low profile packaging
Support for automated flow solder assembly


PDM digital audio output
Stereo/array operation

Proprietary ADC technology
Reduced clock jitter sensitivity
-
Low noise floor modulation
Stable in overload condition


Top port package
1.64V to 3.7V supply

4.00 x 3.00 x 1.03mm thin package design
APPLICATIONS

Mobile telephone handsets


Portable computers
Portable media players


Digital still cameras
Digital video cameras


Bluetooth headsets
Portable navigation devices
BLOCK DIAGRAM
WOLFSON MICROELECTRONICS plc
To receive regular email updates, sign up at http://www.wolfsonmicro.com/enews
Preliminary Technical Data, January 2012, Rev 2.2
Copyright 2012 Wolfson Microelectronics plc
WM7210
Preliminary Technical Data
TABLE OF CONTENTS
DESCRIPTION ....................................................................................................... 1 FEATURES ............................................................................................................ 1 APPLICATIONS..................................................................................................... 1 BLOCK DIAGRAM ................................................................................................ 1 TABLE OF CONTENTS ......................................................................................... 2 PIN CONFIGURATION .......................................................................................... 3 PIN DESCRIPTION ................................................................................................ 3 ORDERING INFORMATION .................................................................................. 3 ABSOLUTE MAXIMUM RATINGS ........................................................................ 4 IMPORTANT ASSEMBLY GUIDELINES .............................................................. 4 RECOMMENDED OPERATING CONDITIONS ..................................................... 4 ACOUSTIC AND ELECTRICAL CHARACTERISTICS ......................................... 5 TERMINOLOGY ............................................................................................................... 5 AUDIO INTERFACE TIMING ........................................................................................... 6 TYPICAL PERFORMANCE ................................................................................... 7 FREQUENCY RESPONSE .............................................................................................. 7 THD RATIO ...................................................................................................................... 7 APPLICATIONS INFORMATION .......................................................................... 8 RECOMMENDED EXTERNAL COMPONENTS .............................................................. 8 CONNECTION TO A WOLFSON AUDIO CODEC .......................................................... 8 RECOMMENDED PCB LAND PATTERNS ..................................................................... 9 PACKAGE DIMENSIONS .................................................................................... 10 IMPORTANT NOTICE ......................................................................................... 11 ADDRESS: .......................................................................................................... 11 REVISION HISTORY ........................................................................................... 12 w
PTD, Rev 2.2, January 2012
2
WM7210
Preliminary Technical Data
PIN CONFIGURATION
PIN DESCRIPTION
PIN
NAME
TYPE
1
VDD
Supply
DESCRIPTION
2
LRSEL
Digital Input
Supply
Channel Select
0 = Data output following falling CLK edge
1 = Data output following rising CLK edge
3
CLK
Digital Input
Clock input
4
DAT
Digital Output
5
GND
Supply
PDM Data Output
Ground
ORDERING INFORMATION
MOISTURE
SENSITIVITY LEVEL
PEAK SOLDERING
TEMPERATURE
o
MSL2A
+260 C
o
MSL2A
+260 C
o
MSL2A
+260 C
o
MSL2A
+260 C
DEVICE
DESCRIPTION
TEMPERATURE
RANGE
WM7210IMS/V
Standard
-40 to +100 C
WM7210IMS/RV
Standard
(tape and reel)
-40 to +100 C
WM7210IMSE/V
Standard Enhanced
-40 to +100 C
WM7210IMSE/RV
Standard Enhanced
(tape and reel)
-40 to +100 C
o
o
o
o
Note:
Reel Quantity = 4800
All devices are Pb-free and Halogen free.
w
PTD, Rev 2.2, January 2012
3
WM7210
Preliminary Technical Data
ABSOLUTE MAXIMUM RATINGS
Absolute Maximum Ratings are stress ratings only. Permanent damage to the device may be caused by continuously operating at
or beyond these limits. Device functional operating limits and guaranteed performance specifications are given under Electrical
Characteristics at the test conditions specified.
ESD Sensitive Device. This device is manufactured on a CMOS process. It is therefore generically susceptible
to damage from excessive static voltages. Proper ESD precautions must be taken during handling and storage
of this device.
Wolfson tests its package types according to IPC/JEDEC J-STD-020 for Moisture Sensitivity to determine acceptable storage
conditions prior to surface mount assembly. These levels are:
MSL1 = unlimited floor life at <30C / 85% Relative Humidity. Not normally stored in moisture barrier bag.
MSL2 = out of bag storage for 1 year at <30C / 60% Relative Humidity. Supplied in moisture barrier bag.
MSL2A = out of bag storage for 4 weeks at <30°C / 60% Relative Humidity. Supplied in moisture barrier bag.
MSL3 = out of bag storage for 168 hours at <30C / 60% Relative Humidity. Supplied in moisture barrier bag.
The Moisture Sensitivity Level for each package type is specified in Ordering Information.
CONDITION
MIN
MAX
Supply Voltage (VDD)
-0.3V
+4.2V
GND-0.3V
VDD+0.3V
-40ºC
+100ºC
Voltage range digital inputs (LRSEL and CLK)
Operating temperature range, TA
Storage temperature prior to soldering
30C max / 60% RH max
Storage temperature after soldering
-40ºC
+100ºC
IMPORTANT ASSEMBLY GUIDELINES
Do not put a vacuum over the port hole of the microphone. Placing a vacuum over the port hole can damage the device. For
information on recommended pick and place vacuum point, refer to the package dimension drawing.
Do not board wash the microphone after a re-flow process. Board washing and the associated cleaning agents can damage
the device. Do not expose to ultrasonic cleaning methods.
Do not use vapour phase re-flow process. The vapour can damage the device.
Please refer to application note WAN_0273 for further assembly and handling guidelines.
RECOMMENDED OPERATING CONDITIONS
SYMBOL
MIN
Analogue Supply Range
PARAMETER
VDD
1.64
Ground
GND
Clock Frequency
FCLK
w
TYP
MAX
UNIT
3.7
V
3.25
MHz
0
1
V
PTD, Rev 2.2, January 2012
4
WM7210
Preliminary Technical Data
ACOUSTIC AND ELECTRICAL CHARACTERISTICS
Test Conditions: VDD=1.8V, 1kHz test signal, CLK=2.4MHz, TA = 25°C
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
Directivity
TYP
MAX
UNIT
Omni-directional
Sensitivity (WM7210)
S
94dB SPL
-29
-26
-23
dBFS
Sensitivity (WM7210E)
S
94 dB SPL
-27
-26
-25
dBFS
THD < 10%
120
Signal to Noise Ratio
SNR
A-Weighted
58
Total Harmonic Distortion
THD
100dB SPL input
0.1
-3dB Low frequency
35
+3dB High frequency
10000
Hz
A-weighted
36
dB SPL
A-weighted
-84
dBFS
217Hz Square Wave
-65
dBFS
Acoustic Overload
Frequency response
Acoustic Noise Floor
Electrical Noise Floor
Power Supply Rejection
PSR
dB SPL
dB
1
%
Hz
100mV pk-pk
Digital Input / Output
CLK Input HIGH Level
VIH
CLK Input LOW Level
VIL
DAT Output HIGH Level
VOH
IOH = +1mA
DAT Output LOW Level
VOL
IOL = -1mA
Input capacitance (CLK)
Maximum load capacitance
(DAT)
0.65 x
VDD
V
0.35 x
VDD
CIN
0.9 x
VDD
V
ISC
0.1 x
VDD
V
100
pF
1
μA
10
mA
0.5
CLOAD
Input Leakage
Short Circuit Output Current
V
DAT connected to GND
pF
Miscellaneous
Current Consumption
Start-up Time
CLK Sleep Frequency
IVDD
Active Mode
650
SLEEP Mode
2
From OFF
10
From SLEEP
10
μA
10
ms
1.0
kHz
TERMINOLOGY
1.
Sensitivity (dBFS) – Sensitivity is a measure of the microphone output response to the acoustic pressure of a 1kHz
94dB SPL (1Pa RMS) sine wave. This is referenced to the output Full Scale Range (FSR) of the microphone.
2.
Full Scale Range (FSR) - Sensitivity, Electrical Noise Floor and Power Supply Rejection are measured with reference
to the output Full Scale Range (FSR) of the microphone. FSR is defined as the amplitude of a 1kHz sine wave output
whose positive peak value reaches 100% density of logic 1s and whose negative peak value reaches 0% density of
logic 1s. This is the largest undistorted 1kHz sine wave that will fit in the digital output numerical range. Note that,
because the definition of FSR is based on a sine wave, it is possible to support a square wave test signal output
whose level is +3dBFS.
3.
Signal-to-Noise Ratio (dB) – SNR is a measure of the difference in level between the output response of a 1kHz 94dB
SPL sine wave and the idle noise output.
Total Harmonic Distortion (%) – THD is the ratio of the RMS sum of the harmonic distortion products in the specified
bandwidth (see note below) relative to the RMS amplitude of the fundamental (ie. test frequency) output.
4.
5.
All performance measurements are carried out with 20kHz low pass ‘brick-wall’ filter and, where noted, an A-weighted
filter. Failure to use these filters will result in higher THD and lower SNR values than are found in the Acoustic and
Electrical Characteristics. The brick wall filter removes out of band noise.
w
PTD, Rev 2.2, January 2012
5
WM7210
6.
Preliminary Technical Data
SLEEP Mode is enabled when the CLK input is below the CLK Sleep Frequency noted above. This is a power-saving
mode. Normal operation resumes automatically when the CLK input is above the CLK Sleep Frequency. Note that the
VDD supply is still required in SLEEP mode.
AUDIO INTERFACE TIMING
tCY
CLK
(input)
DAT
(LRSEL = 1)
tL_DIS
tL_EN
DAT
(LRSEL = 0)
tR_DIS
tR_EN
DAT is high-impedance (hi-z) when not outputting data
Figure 1 Digital Microphone Interface Timing
Test Conditions
The following timing information is valid across the full range of recommended operating conditions.
PARAMETER
SYMBOL
MIN
TYP
MAX
UNIT
325
976
ns
60:40
40:60
Digital Microphone Interface Timing
CLK cycle time
tCY
CLK duty cycle
DAT enable from rising CLK edge (LRSEL = 1)
tL_EN
DAT disable from falling CLK edge (LRSEL = 1)
tL_DIS
DAT enable from falling CLK edge (LRSEL = 0)
tR_EN
DAT disable from rising CLK edge (LRSEL = 0)
tR_DIS
18
ns
16
18
ns
ns
16
ns
Notes:
1.
The DAT output is high-impedance when not outputting data; this enables the outputs of two microphones to be
connected together with the data from one microphone interleaved with the data from the other. (The microphones
must be configured to transmit on opposite channels in this case.)
2.
3.
In a typical configuration, the Left channel is transmitted following the rising CLK edge (LRSEL = 1). In this case, the
Left channel should be sampled by the receiving device on the falling CLK edge,
Similarly, the Right channel is typically transmitted following the falling CLK edge (LRSEL = 0). In this case, the Right
channel should be sampled by the receiving device on the rising CLK edge.
w
PTD, Rev 2.2, January 2012
6
WM7210
Preliminary Technical Data
TYPICAL PERFORMANCE
FREQUENCY RESPONSE
Sensitivity vs. Frequency
(Relative to Sensitivity @ 1kHz)
10.0
8.0
6.0
Sensitivity (dB)
4.0
2.0
0.0
‐2.0
‐4.0
‐6.0
‐8.0
‐10.0
10.0
100.0
1000.0
10000.0
Frequency (Hz)
THD RATIO
w
PTD, Rev 2.2, January 2012
7
WM7210
Preliminary Technical Data
APPLICATIONS INFORMATION
RECOMMENDED EXTERNAL COMPONENTS
It is recommended to connect a 0.1µF decoupling capacitor between the VDD and GND pins of the
WM7210. A ceramic 0.1µF capacitor with X7R dielectric or better is suitable. The capacitor should be
placed as close to the WM7210 as possible.
CONNECTION TO A WOLFSON AUDIO CODEC
Wolfson provides a range of audio CODECs incorporating a digital microphone input interface; these
support direct connection to digital microphones such as the WM7210.
Stereo connection of two WM7210 digital microphones to the WM8994 CODEC is illustrated in Figure
2.
A 0.1µF decoupling capacitor is recommended; this should be positioned close to the VDD pin of the
WM7210. A ceramic 0.1µF capacitor with X7R dielectric or better is suitable.
Further information on the WM8994 is provided in the product datasheet, which is available from the
Wolfson website. The equivalent connections can be made to other Wolfson devices supporting a
digital microphone interface.
VDD
WM7210
VDD
WM8994
CLK
0.1 F
DAT
LRSEL
DMICCLK
DMICDAT1
GND
VDD
WM7210
VDD
CLK
0.1 F
DAT
LRSEL
GND
Figure 2 Stereo WM7210 Digital Microphone Connection to WM8994
w
PTD, Rev 2.2, January 2012
8
WM7210
Preliminary Technical Data
RECOMMENDED PCB LAND PATTERNS
2.30
1.30
Figure 3 Recommended Customer PCB Land Pattern
(Note that all other dimensions can be obtained from the package dimensions)
w
PTD, Rev 2.2, January 2012
9
WM7210
PACKAGE DIMENSIONS
Preliminary Technical Data
MS5: PACKAGE 4.00 x 3.00 x 1.03 mm BODY
DM074.C
0.1 C
D
PIN1 CORNER
M
V
0.30 X 45°
R
R 0.15
W
1
E
2
L
1
2
4
3
X
PNP Vacuum
Point
K
5
R 0.45
0.1 C
R 0.55
J
U
N
TOP VIEW
R 0.3
S
F
Y
0.05 C
F
H
P
BOTTOM VIEW
R 0.1
T
-C-
A
SIDE VIEW
Dimensions (mm)
Symbols
MIN
NOM
MAX
A
0.96
1.03
1.10
D
3.90
4.00
4.10
E
2.90
3.00
3.10
F
H
0.05
0.30
0.10
0.35
0.15
0.40
J
1.35
1.50
1.65
K
1.35
1.50
1.65
L
2.75
M
3.75
N
1.10
PNP
Vacuum Point
P
R
0.35
0.35
0.40
0.40
0.45
0.45
S
0.76
0.79
0.82
T
0.61
0.64
0.67
U
0.35
0.40
0.45
V
0.30
0.35
0.40
W
0.40
0.45
0.50
X
0.35
0.40
0.45
Y
0.90
0.95
1.00
0.65
0.70
0.75
1
2
1.31
NOTE
Gasket Area
NOTES:
1. THE SEATING PLANE IS REPRESENTED BY PRIMARY DATUM -C2. THE DEVIATION FROM THE SEATING PLANE DUE TO WARPAGE OR TWIST IS SPECIFIED AS MAX 50m (FLATNESS).
3. LID SHOULD BE PARALLEL TO THE SEATING PLANE ±50m.
w
PTD, Rev 2.2, January 2012
10
Preliminary Technical Data
WM7210
IMPORTANT NOTICE
Wolfson Microelectronics plc (“Wolfson”) products and services are sold subject to Wolfson’s terms and conditions of sale,
delivery and payment supplied at the time of order acknowledgement.
Wolfson warrants performance of its products to the specifications in effect at the date of shipment. Wolfson reserves the
right to make changes to its products and specifications or to discontinue any product or service without notice. Customers
should therefore obtain the latest version of relevant information from Wolfson to verify that the information is current.
Testing and other quality control techniques are utilised to the extent Wolfson deems necessary to support its warranty.
Specific testing of all parameters of each device is not necessarily performed unless required by law or regulation.
In order to minimise risks associated with customer applications, the customer must use adequate design and operating
safeguards to minimise inherent or procedural hazards. Wolfson is not liable for applications assistance or customer
product design. The customer is solely responsible for its selection and use of Wolfson products. Wolfson is not liable for
such selection or use nor for use of any circuitry other than circuitry entirely embodied in a Wolfson product.
Wolfson’s products are not intended for use in life support systems, appliances, nuclear systems or systems where
malfunction can reasonably be expected to result in personal injury, death or severe property or environmental damage.
Any use of products by the customer for such purposes is at the customer’s own risk.
Wolfson does not grant any licence (express or implied) under any patent right, copyright, mask work right or other
intellectual property right of Wolfson covering or relating to any combination, machine, or process in which its products or
services might be or are used. Any provision or publication of any third party’s products or services does not constitute
Wolfson’s approval, licence, warranty or endorsement thereof. Any third party trade marks contained in this document
belong to the respective third party owner.
Reproduction of information from Wolfson datasheets is permissible only if reproduction is without alteration and is
accompanied by all associated copyright, proprietary and other notices (including this notice) and conditions. Wolfson is
not liable for any unauthorised alteration of such information or for any reliance placed thereon.
Any representations made, warranties given, and/or liabilities accepted by any person which differ from those contained in
this datasheet or in Wolfson’s standard terms and conditions of sale, delivery and payment are made, given and/or
accepted at that person’s own risk. Wolfson is not liable for any such representations, warranties or liabilities or for any
reliance placed thereon by any person.
ADDRESS:
Wolfson Microelectronics plc
Westfield House
26 Westfield Road
Edinburgh
EH11 2QB
Tel :: +44 (0)131 272 7000
Fax :: +44 (0)131 272 7001
Email :: [email protected]
w
PTD, Rev 2.2, January 2012
11
WM7210
Preliminary Technical Data
REVISION HISTORY
DATE
REV
25/09/09
1.0
5/3/10
1.1
25/10/10
2.0
27/1/11
2.1
ORIGINATOR
PH
CHANGES
‘Top Port’ added to device title
ENL abbreviation deleted from Electrical Characteristics
Acoustic and Electrical Characteristics terminology updated
Decoupling capacitor requirement described in ‘Connection to a Wolfson Audio
CODEC’ section
21/2/11
2.1
KC
Updated the LRSEL pin description , Timing diagram and notes for the rising and
falling clock edges.
Updated the reel quantity.
Updated the start up time.
Updated the input capacitance
Updated the sleep mode current 2uA as typical value
Added new frequency response curve
Updated the acoustic Characteristics(+3dB frequency response, acoustic noise
floor, PSR to –ve value)
Updated the frequency response and THD curves.
06/09/11
2.1
JMacD
20/12/11
2.2
KC
Package Diagram updated to DM074C with additional tolerance and chamfer
detail.
Introduced E variant with sensitivity +/-1dB
Added E variant ordering info
Added voltage range digital input
Updated the CODEC to WM8994
Added Reference to WAN_0273
w
PTD, Rev 2.2, January 2012
12