w WM7130A, WM7130AE Bottom Port Analogue Silicon Microphone DESCRIPTION FEATURES The WM7130A is a low-profile silicon analogue microphone. It offers high Signal to Noise Ratio (SNR) and low power consumption and is suited to a wide variety of consumer applications. Low supply current 140µA The WM7130A incorporates Wolfson’s proprietary CMOS/MEMS membrane technology, offering high reliability and high performance in a miniature, low-profile package. The WM7130A is designed to withstand the high temperatures associated with automated flow solder assembly processes. (Note that conventional microphones can be damaged by this process.) Low profile packaging Support for automated flow solder assembly Analogue output Bottom Port Package 1.5V to 3.7V supply 3.76mm x 3.00mm x 1.10mm Package The WM7130AE 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. APPLICATIONS High SNR; selectable sensitivity tolerance options - WM7130A - SNR 61dB, Sensitivity +/-3dB - WM7130AE - SNR 61dB, Sensitivity +/-1dB Mobile phone handsets Portable media players Digital still cameras Digital video cameras Bluetooth headsets Portable navigation devices Portable games consoles BLOCK DIAGRAM WOLFSON MICROELECTRONICS plc To receive regular email updates, sign up at http://www.wolfsonmicro.com/enews Pre-Production, April 2012, 3.1 Copyright 2012 Wolfson Microelectronics plc WM7130A Pre-Production 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 TYPICAL PERFORMANCE ................................................................................... 6 FREQUENCY RESPONSE .............................................................................................. 6 THD RATIO ...................................................................................................................... 6 APPLICATIONS INFORMATION .......................................................................... 7 RECOMMENDED EXTERNAL COMPONENTS .............................................................. 7 CONNECTION TO A WOLFSON AUDIO CODEC .......................................................... 8 RECOMMENDED PCB LAND PATTERNS ..................................................................... 9 PACKAGE DIMENSIONS .................................................................................... 10 IMPORTANT NOTICE ......................................................................................... 11 ADDRESS: ..................................................................................................................... 11 REVISION HISTORY ........................................................................................... 12 w PP, Rev 3.1, April 2012 2 WM7130A Pre-Production PIN CONFIGURATION PIN DESCRIPTION PIN NAME TYPE 1 OUTPUT Analogue Output DESCRIPTION 2 GND Supply 3 GND Supply Analogue ground 4 VDD Supply Analogue supply 5 GND Supply Analogue ground 6 GND Supply Analogue ground Microphone analogue output signal Analogue 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 WM7130AIMS/V Standard -40 to +100 C WM7130AIMS/RV Standard (tape and reel) -40 to +100 C WM7130AIMSE/V Enhanced -40 to +100 C WM7130AIMSE/RV Enhanced (tape and reel) -40 to +100 C o o o o Note: Reel quantity = 5000 All devices are Pb-free and Halogen free. w PP, Rev 3.1, April 2012 3 WM7130A Pre-Production 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 <30C / 85% Relative Humidity. Not normally stored in moisture barrier bag. MSL2 = out of bag storage for 1 year at <30C / 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 <30C / 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 -0.3V +4.2V Operating temperature range, TA -40ºC +100ºC Storage temperature prior to soldering 30C 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. 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 a 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 PARAMETER SYMBOL MIN Analogue Supply Range VDD 1.5 Ground GND w TYP 0 MAX UNIT 3.7 V V PP, Rev 3.1, April 2012 4 WM7130A Pre-Production ACOUSTIC AND ELECTRICAL CHARACTERISTICS Test Conditions: VDD=2.1V, 1kHz test signal, TA = 25°C PARAMETER SYMBOL TEST CONDITIONS MIN Sensitivity (WM7130A) S 94dB SPL -41 Sensitivity (WM7130AE) S 94dB SPL -39 Directivity TYP MAX UNIT -38 -35 dBV -38 -37 Omni-directional Acoustic Overload No Load dBV 127 dB SPL A-Weighted 61 dB THD < 10% Signal to Noise Ratio SNR Total Harmonic Distortion THD 104dB SPL 0.25 % DR A-Weighted, 89 dB Dynamic Range Noise floor to 1% THD Frequency Response -3dB Low Frequency 62 Hz +3dB High Frequency 12000 Hz Acoustic Noise Floor A-Weighted 33 dB SPL Electrical Noise Floor A-Weighted -99 dBV 100mV RMS, 217Hz 50 Power Supply Rejection Ratio PSRR Current Consumption IVDD 140 Output DC Impedance ZOUT 100 dB 190 µA Ω TERMINOLOGY 1. Sensitivity (dBV) - Sensitivity is a measure of the microphone output response to the acoustic pressure of a 1kHz 94dB SPL (1Pa RMS) sine wave. 2. 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. 3. Total Harmonic Distortion (dB) – THD is the ratio of the RMS sum of the harmonic distortion products in the specified bandwidth (see note below) relative to the amplitude of the fundamental (ie. test frequency) output. 4. Dynamic Range (dB) – DR is the ratio of the 1% THD microphone output level (in response to a sine wave input) and the idle noise output level. 5. All performance measurements are carried out with 20 kHz 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 low pass filter removes out of band noise. w PP, Rev 3.1, April 2012 5 WM7130A Pre-Production TYPICAL PERFORMANCE FREQUENCY RESPONSE Sensitivity vs frequency (Relative to Sensitivity @KHz) 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 100000.0 Frequency (Hz) THD RATIO THD vs Input Sound Pressure Level 10.0 9.0 8.0 7.0 THD (%) 6.0 5.0 4.0 3.0 2.0 1.0 0.0 90.0 95.0 100.0 105.0 110.0 115.0 120.0 125.0 130.0 135.0 Input Sound Pressure Level (dB SPL) w PP, Rev 3.1, April 2012 6 WM7130A Pre-Production APPLICATIONS INFORMATION RECOMMENDED EXTERNAL COMPONENTS Figure 1 WM7130A Recommended External Components A DC-blocking output capacitor is required on the OUTPUT pin, as illustrated in Figure 1. A single capacitor is required for a single-ended connection. The capacitor must be correctly selected as it affects the cut-off frequency of the output path. A low cut-off frequency is desirable as it means there is no significant filtering of the audio bandwidth. The 3dB cut-off frequency of the output path is given by the equation below, where C is the output capacitance and R is the input resistance of the other circuit. A typical recommended configuration, with 1uF DC-blocking capacitor and 20kΩ minimum input circuit impedance, gives a 3dB cut-off frequency of 10Hz or less. Tantalum electrolytic capacitors are particularly suitable for the DC-blocking components as they offer high stability in a small package size w PP, Rev 3.1, April 2012 7 WM7130A Pre-Production CONNECTION TO A WOLFSON AUDIO CODEC Wolfson provides a range of audio CODECs incorporating an analogue microphone input interface; these support connection to silicon microphones such as the WM7130A. The recommended connection of a WM7130A silicon microphone to the WM8994 is illustrated in Figure 2 (for single-ended mode) and Figure 3 (for pseudo-differential mode). A DC blocking capacitor is required, as described in the previous section. A 1µF decoupling capacitor is also recommended; this should be positioned close to the VDD pin of the WM7130A. 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 in a similar manner. Figure 2 WM7130A Silicon Microphone Single-ended Connection to WM8994 Figure 3 WM7130A Silicon Microphone Pseudo-differential Connection to WM8994 w PP, Rev 3.1, April 2012 8 WM7130A Pre-Production RECOMMENDED PCB LAND PATTERNS 1.93mm Figure 4 Recommended Customer PCB Land Pattern (Note that all other dimensions can be obtained from the package dimensions) w PP, Rev 3.1, April 2012 9 WM7130A Pre-Production PACKAGE DIMENSIONS w PP, Rev 3.1, April 2012 10 Pre-Production WM7130A 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 PP, Rev 3.1, April 2012 11 WM7130A Pre-Production REVISION HISTORY DATE REV ORIGINATOR 02/05/11 2.0 JKC First release of AE variant CHANGES 2.0 KC First page package dimension Added the WM7130AE Updated the features for WM7130AE Updated the frequency response curve, the THD curves, Updated the +3dB frequency response to 14200Hz. Updated WM7130AE frequency response performance, and sensitivity performance Updated the reel quantity to 4800 Remove the 20k ohms test condition. Modified the wording for 1uF and 20kohms to ensure 10hz low frequency cut off 2.0 JMacD Package diagram updated: 1. References and dimension letters changed to be consistent with all MEMS package diagrams. Updated lid design with adjusted dimensions. Pin numbers added. 2. Pin out changed to match datasheet 2.0 TS 06/05/11 2.0 JMacD/MR Acoustic and Electrical Char: Acoustic Overload updated to 127 01/07/11 2.1 JMacD/MR Package Drawing update: - Updated porthole positional tolerances. 04/07/11 2.2 JMacD/MR Reel quantity updated to 5000. - Updated theta3 tolerance. Order Code for Enhanced, 62Hz roll off updated to: - WM7130AIMSE/V - WM7130AIMSE/RV 12/09/11 3.0 KC/MR Order code added for standard product: - WM7130AIMS/V - WM7130AIMS/RV 12/09/11 3.0 KC/MR 17/02/12 3.1 KC/JMacD Frequency response curve and SNR parameter updated. Acoustic and Electrical Characteristics: Sensitivity unit changed from dB to dBV. Updated Terminology 1. Dynamic Range added, DR definition added. w PP, Rev 3.1, April 2012 12