2403 260 00098 SPEAKER-1115-4-SC-COBRA SF The 11×15×4 mm COBRA SF is high-end miniature speaker of rectangular shape with lateral sound outlets. Specifically designed for sidefiring applications, this speaker version enables a reduced application height in small, slim consumer devices, such as music phones, smartphones or tablet computers where high quality sound and maximum space efficiency are required. In addition, COBRA SF features Knowles’ advanced membrane technologies resulting in a state-of-the-art silicone membrane. This unique silicone membrane enables ultra-high excursion rates and superior robustness. Features: • Lateral sound outlet integrated in cover of speaker • Significant height reduction for side-firing applications • 100% in-line measurement of all specified acoustical and electrical parameters • Pre-tested and integrated side-porting acoustics • Manufactured to the highest standards • High power handling capacity of 1000mW This document contains information which is confidential and/or proprietary to Knowles Electronics, LLC or its affiliates. Do not distribute or use the information contained herein without permission from an authorized representative of Knowles Page 1 of 20 ©2012 Knowles Electronics 2403 260 00098 Contents 1. Theory of operation............................................................................................................................. 3 2. Mechanical Layout and Dimensions.................................................................................................... 4 2.1. Main dimensions .........................................................................................................................4 2.2. PWB layout & electric polarity ....................................................................................................5 2.3. Magnetic polarity ........................................................................................................................5 2.4. Spring force .................................................................................................................................6 2.5. Part marking/labeling ..................................................................................................................7 2.6. Material list..................................................................................................................................8 2.7. Force on component ...................................................................................................................9 3. Electrical and Acoustical Specifications............................................................................................. 10 3.1. Frequency response ..................................................................................................................10 3.2. Electro-acoustic parameters .....................................................................................................11 3.3. Power handling..........................................................................................................................11 3.4. Measured parameters ...............................................................................................................12 3.5. Measurement setup ..................................................................................................................12 3.6. Measurement adapter ..............................................................................................................13 4. Environmental Conditions ................................................................................................................. 14 4.1. Storage.......................................................................................................................................14 4.2. Transportation ...........................................................................................................................14 4.3. Functionality ..............................................................................................................................14 5. Environmental Tests .......................................................................................................................... 15 5.1. Qualification tests......................................................................................................................15 5.2. Reliability tests ..........................................................................................................................15 5.3. Sample size, sequence...............................................................................................................15 5.4. Period of shelf-life .....................................................................................................................15 5.5. Testing procedures ....................................................................................................................15 6. Related Documents ........................................................................................................................... 19 7. Change History .................................................................................................................................. 20 8. Disclaimer .......................................................................................................................................... 20 Release – Revision: A Page 2 of 20 ©2011 Knowles Electronics 2403 260 00098 1. Theory of operation SPEAKER-1115-4-SC-COBRA SF is an electrodynamic transducer, designed to translate electrical analog signals into acoustic waves. The input signal is fed into a coil which is exposed to a permanent magnetic field and where a membrane is attached to. Through the principle of the resulting electromagnetic force, the membrane is moved according to the contents of the input signal and thus emitting sound by the air shifted. Release – Revision: A Page 3 of 20 ©2011 Knowles Electronics 2403 260 00098 2. Mechanical Layout and Dimensions 2.1. Main dimensions Release – Revision: A Page 4 of 20 ©2011 Knowles Electronics 2403 260 00098 2.2. PWB layout & electric polarity 2.3. Magnetic polarity Release – Revision: A Page 5 of 20 ©2011 Knowles Electronics 2403 260 00098 2.4. Spring force SPRING FORCE TABLE Force at Basket level 0.0 mm Force at Start Working position 0.5 mm uncompressed (delivery position) 0.65 ±0.15mm Force at PPP level -0.2 mm Release – Revision: A Page 6 of 20 min. 0.6 N min. 0.3 N 0.0 N max 1.2 N ©2011 Knowles Electronics 2403 260 00098 2.5. Part marking/labeling The samples have a serial number on bottom (pot) side Release – Revision: A Page 7 of 20 ©2011 Knowles Electronics 2403 260 00098 2.6. Material list Material of basket: Polycarbonate Material of membrane: Silicone Material of membrane frame Polybutylene Terephthalate (PBT) Material of pot: soft magnetic Iron Material of magnet: Nd Fe B Material of contact CrNi-Steel, gold plated Material of cover: Polycarbonate Dimensions (in mm): 11 × 15 × 4 Mass: 1.56 g Release – Revision: A Page 8 of 20 ©2011 Knowles Electronics 2403 260 00098 2.7. Force on component STATE FROM FRONT TO BACK (GASKET AREA) FROM SIDE 1 TO SIDE 3 FROM SIDE 2 TO SIDE 4 TO POT TO MEMBRANE PULL OFF FORCE Release – Revision: A FORCES ON DIFFERENT STATE OF COMPONENT MIN. SURFACE OF MAX. PERMANENT PRESSURE [mm²] FORCE [N] 10 3 10 - 10 10 10 0 0 Page 9 of 20 MAX. HANDLING FORCE [N] 15 15 15 15 0 20 ©2011 Knowles Electronics 2403 260 00098 3. Electrical and Acoustical Specifications 3.1. Frequency response 140 60 130 50 120 40 110 30 100 20 90 10 THD [%] SPL [dB rel 20uPa] Typical frequency response measured on baffle according to chapter 3.5 (distance d = 1cm, p = 1000mW, 1cm³) 0 80 100 1000 10000 f [Hz] SPL [dB] f [Hz] 300 700 800 850 900 2000 3000 3500 4000 6000 Release – Revision: A THD Tolerance window Frequency Response lower limit upper limit (floating) (floating) f [dB] [dB] [Hz] 88.8 102.8 300 119.5 450 112.5 650 119.5 1000 112.5 1300 110 115 5500 115 6000 110 10000 118.5 116.8 132.8 7000 116.8 - 8000 - 132.8 10000 102.8 116.8 Page 10 of 20 Limit THD upper limit [%] 50 37.5 19 10 5 5 6 6 ©2011 Knowles Electronics 2403 260 00098 3.2. Electro-acoustic parameters Loudspeaker mounted in adapter acc. to 3.5. 1. Rated impedance Z: 6Ω 2. Voice coil DC resistance R: 5.4Ω±10% 3. Resonance frequency (measured @1cm³, 1000mW) f0: 780Hz±10% 4. Maximum usable excursion (peak-to-peak) xmax: 0.74mmp-p 5. Nominal characteristic sensitivity (measured at 1W in 1cm, calculated to 1m average from 2kHz to 3kHz, thermal compression included) 73.5±2.5dB 5.1 Measured characteristic sensitivity (at 1W in 10cm) average from 2kHz to 3kHz 86.5±2dB 6. THD according chapter 3.1 7. Rub & buzz no audible Rub & Buzz All acoustic measurements at 23±2°C 3.3. Power handling Speaker mounted in 1cm³ test device (open front) 1. Max sine Power 1000mW (RMS) 2. Max short term power (70°C, 1 sec. ON / 60sec. OFF) 1200mW (RMS) 3. Max continuous power (70°C, 500h) 1000mW (RMS) nd (pink noise, 2 order high pass filtered, -3dB at 1.2kHz, crest factor 2) (pink noise, 2nd order high pass filtered, -3dB at 800Hz, crest factor 2) Release – Revision: A Page 11 of 20 ©2011 Knowles Electronics 2403 260 00098 3.4. Measured parameters 3.4.1. Sensitivity SPL is expressed in dB rel 20µPa, computed according to IEC 268-5. Measurement set up and parameters according chapter 3.5. This test is performed for 100% of products in the production line. 3.4.2. Frequency response Frequency response is measured according test set up in chapter 3.3 data sheet and checked against the tolerance window defined in chapter 3.5. This Test is performed for 100% of products in the production line. 3.4.3. Total harmonic distortion (THD) Is measured according IEEE and test set up in chapter 3.5. This test is performed for 100% of products in the production line. 3.4.4. Rub & buzz Rub & buzz will be measured in the Inline-measuring device with a sinusoidal sweep. Rub and buzz is defined as the maximum peak sound pressure in transmission range of the 5kHz high pass filter. This test is performed for 100% of products in the production line. 3.5. Measurement setup IEC BAFFLE Rq, including wiring < 0,3Ω Freefield microphone 1/4“ Power amplifier analyzer • ≈ 1cm³ • • d frequency response THD rub & buzz Measurement adapter Measurement signal: Logarithmic sine sweep, 1.5s, 22kHz-180Hz Release – Revision: A Page 12 of 20 ©2011 Knowles Electronics 2403 260 00098 3.6. Measurement adapter Release – Revision: A Page 13 of 20 ©2011 Knowles Electronics 2403 260 00098 4. Environmental Conditions 4.1. Storage The transducer fulfills the specified data after treatment according to the conditions of ETS 300 019-2-1 Specification of environmental test: Storage Test spec. T 1.2: Weather protected, not temperature controlled storage locations. 4.2. Transportation The transducer fulfills the specified data after treatment according to the conditions of ETS 300 019-2-2 Specification of environmental test: Transportation Test Spec. T 2.3: Public Transportation 4.3. Functionality The transducer fulfills the specified data after treatment according to the conditions of ETS 300 019-2-5 ETS 300 019-2-7 Release – Revision: A Specification of environmental test: Ground vehicle installations Test spec. T 5.1: Protected installation Specification of environmental test: Portable and non-stationary use Test spec. T 7.3E: Partly weather protected and non-weather protected locations. Page 14 of 20 ©2011 Knowles Electronics 2403 260 00098 5. Environmental Tests 5.1. Qualification tests According to our milestone plan (Product Creation Process), a complete qualification test will be done at design validation of products manufactured under serial conditions. 1x per year and product family a requalification takes place. The qualification process covers all tests described under 4.5 and a complete inspection. 5.2. Reliability tests 1x per month and product family samples are taken and submitted to tests described under 4.5.2 5.3. Sample size, sequence Unless otherwise stated 20 arbitrary new samples will be used to perform each test for both, qualification and requalification test as described under 4.1 and 4.2. 5.4. Period of shelf-life The period of shelf-life is 2 years. 5.5. Testing procedures 5.5.1. Storage tests 5.5.1.1. Cold storage test Parameter Test Method and Conditions Duration Evaluation Standard Low Temperature Storage -40°C 168h Measurements after 2 hours recovery time. (Ref. EN 60068-2-1) rel. humidity not controlled All samples fully operable. All acoustical parameters according specification with tolerances increased by 50 %. 5.5.1.2. Heat storage test Parameter Test Method and Conditions Duration Evaluation Standard Dry Heat Storage +85°C 168h (Ref. EN 60068-2-2) rel. humidity not controlled Measurements after 2 hours recovery time. All samples fully operable. All acoustical parameters according specification with tolerances increased by 50 %. Release – Revision: A Page 15 of 20 ©2011 Knowles Electronics 2403 260 00098 5.5.1.3. Temperature cycle test Parameter Test Method and Conditions Duration Evaluation Standard Change of Temperature -40°C/+85°C 5 cycles (Ref. EN 60068-2-14) Transition time <3 min. See Figure 4-1 below >2h for each temperature Measurements after 2 hours recovery time. All samples fully operable. All acoustical parameters according specification with tolerances increased by 50 %. +85°C -40°C 2h 3m 2h 3m 2h 3m 2h 3m 2h 3m 2h 3m 2h 3m 2h 3m 2h 3m 2h 3m Figure 4-1: Temperature Cycle Test 5.5.1.4. Temperature/humidity cycle test Parameter Test Method and Conditions Duration Evaluation Standard Damp heat, cyclic +25°C/+55°C 6 cycles. (Ref. IEC 60068-2-30) 90% to 95% RH. 12h at each temperature Measurements after 2 hours recovery time. Temp. change time <3h See Figure 4-2 below All samples fully operable. All acoustical parameters according specification with tolerances increased by 50 %. Caution: no condensed water on products! +55°C +25°C 9h 3h 9h 3h 9h 3h 9h 3h 9h 3h 9h 3h 9h 3h 9h 3h 9h 3h 9h 3h 9h 3h 9h 3h Figure 4-2: Temperature / Relative Humidity Cycle Test Release – Revision: A Page 16 of 20 ©2011 Knowles Electronics 2403 260 00098 5.5.2. Operating tests 5.5.2.1. Cold operation test Parameter Test Method and Conditions Duration Evaluation Standard Cold Operation Test -20°C 72h (Ref. EN 60068-2-1) rel. humidity not controlled Measurements after 2 hours recovery time. All samples fully operable. THD may be increased after test. All other acoustical parameters according specification with tolerances increased by 50 %. signal acc. chapter 3.3 5.5.2.2. Heat operation test Parameter Test Method and Conditions Duration Evaluation Standard Dry Heat Operation +70°C 500h (Ref. EN 60068-2-2) rel. humidity not controlled Measurements after 2 hours recovery time. All samples fully operable. The allowable change in sensitivity shall not be greater than 3 dB. All other acoustical parameters according specification with tolerances increased by 50 %. signal acc. chapter 3.3 5.5.3. Salt mist test Parameter Test Method and Conditions Duration Evaluation Standard Salt Mist The part must be subjected to 2 hours spray of 5% NaCl salt mist, at 35°C then be left at 40°C and 95% RH for 22h. 3 cycles The samples shall be washed after the test with distilled water and dried at T< 50°C. (Ref. IEC60068-2-52, Kb / Severity 2 Release – Revision: A Component may have reduced performance, but must still function properly. The allowable sensitivity difference shall not be greater than ±3dB from initial sensitivity. Page 17 of 20 ©2011 Knowles Electronics 2403 260 00098 5.5.4. Guided free fall test - protected product Parameter Test Method and Conditions Conditions / Sample size Evaluation Standard Mechanical shock Speaker in drop test box or representative mechanics from a height of 1.5m onto concrete floor. 30 units Two drops on each side (2x6) Component may have reduced performance, but must still function properly. The allowable sensitivity difference shall not be greater than ±3dB from initial sensitivity. (Ref. IEC60068-2-32 Ed), Procedure 1 One drop on each edge (1x12) Two drops on each corner (2x8) (40 drops in total) 5.5.5. Random free fall test (tumble test) – protected product Parameter Test Method and Conditions Conditions / Sample size Evaluation Standard Impact durability (in a Tumble Tester) Speaker in drop test box or representative mechanics. Random drops on steel base. 30 units Component may have reduced performance, but must still function properly. The allowable sensitivity difference shall not be greater than ±3 dB from initial sensitivity. (Ref. IEC60068-2-32 Ed) 180 drops, 1m DUT power off (SPR a7.1.1) 5.5.6. Resistance to electrostatic discharge Parameter Test Method and Conditions Conditions / Sample size Evaluation Standard Resistance to ESD One pole is grounded and the ESD pulse is applied to the other pole. The speaker must be stressed first with one polarisation and then with the other polarisation. DUT must be discharged between each ESD exposure. 10 exposures on each polarity / 5 units All samples fully operable. IEC61000-4-2 Level 4 (SPR c 2.5.1) DUT Power off All acoustical parameters according specification with tolerances increased by 50%. Level 4: contact +/- 8kV, air +/- 15kV Release – Revision: A Page 18 of 20 ©2011 Knowles Electronics 2403 260 00098 6. Related Documents IEC 268-5 IEC 68-2 EN 60068-2 ISO 2859 - 1 ISO 3951 ETS 300 019-2-1 ETS 300 019-2-2 ETS 300 019-2-5 ETS 300 019-2-7 Release – Revision: A Sound System equipment Part 5: Loudspeaker Environmental testing Environmental testing Sampling procedures for inspection by attributes Part 1: Sampling plans indexed by acceptable quality level (AQL) for lot-by-lot inspection Sampling procedures and charts for inspection by variables for percent defectives. Specification of environmental test: Storage Test spec. T 1.2: Weather protected, not temperature controlled storage locations Specification of environmental test: Transportation Test spec. T 2.3: Public Transportation Specification of environmental test: Ground vehicle installations Test spec. T 5.1: Protected installation Specification of environmental test: Portable and non-stationary use Test spec. T 7.3E: Partly weather protected and non-weather protected locations Page 19 of 20 ©2011 Knowles Electronics 2403 260 00098 7. Change History Status Version Release 8. A Date 05.08.13 ECR 4015 Comment / Changes Initials of owner First release BW/CP/ZG/EP/SG Disclaimer Stresses above the Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only. The device may not function when operated at these or any other conditions beyond those indicated under “Electrical and Acoustical Specifications”. Exposure beyond those indicated under “Electrical and Acoustical Specifications” for extended periods may affect device reliability. This product is not qualified for use in automotive applications Frequency range in telecom application: 300 Hz – 3.4 kHz The information contained in this literature is based on our experience to date and is believed to be reliable and it is subject to change without notice. It is intended as a guide for use by persons having technical skill at their own discretion and risk. We do not guarantee favorable results or assume any liability in connection with its use. Dimensions contained herein are for reference purposes only. For specific dimensional requirements consult factory. This publication is not to be taken as a license to operate under, or recommendation to infringe any exiting patents. This supersedes and voids all previous literature. Release – Revision: A Page 20 of 20 ©2011 Knowles Electronics