AN2344 Freescale Semiconductor / Motorola, AN2344 Datasheet
AN2344
Related parts for AN2344
AN2344 Summary of contents
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... Freescale Semiconductor, Inc. Application Note AN2344/D Rev. 0, 10/2002 HC908EY16 EMI Radiated Emissions Results by Andy McKechan Applications Engineering Motorola, East Kilbride Introduction Electromagnetic interference (EMI major concern in the automotive industry as the typical car contains a large number of electronic modules in a relatively small area. If any of these modules emit high levels of unwanted electromagnetic noise there is a possibility that the functionality of other modules may be adversely affected ...
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... Freescale Semiconductor, Inc. AN2344/D SAE J1752/3 Radiated Emissions Testing The remainder of this document covers a set of EMI radiated emissions tests performed in accordance with the SAE J1752/3 specification J1752/3 “Electromagnetic Compatibility Measurement Procedure for Integrated Circuits – Integrated Circuit Radiated Emissions Measurement Procedure 150 kHz to 1000 MHz, TEM Cell” ...
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... R5 PTE0/TXD VDD 24 10K R4 VDD PTE1/RXD TP4 CONNECTION TO FUNCTION GENERATOR Figure 1. TEM Cell PCB Schematic Go to: www.freescale.com AN2344/D TEM Cell Test Board Information Schematic. 2 VSS C10 22pF Y1, R8, R10, C9 and C10 are not fitted when ICG is used. C9 22pF VSS Title MC68HC908EY16 SAE J1752/3 EMC BOARD ...
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... Freescale Semiconductor, Inc. AN2344/D 4 HC908EY16 EMI Radiated Emissions Results For More Information On This Product, Figure 2. TEM CELL PCB TOP LAYER Go to: www.freescale.com MOTOROLA ...
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... Freescale Semiconductor, Inc. MOTOROLA HC908EY16 EMI Radiated Emissions Results For More Information On This Product, Figure 3. TEM CELL PCB SIGNAL LAYER Go to: www.freescale.com AN2344/D TEM Cell Test Board Information 5 ...
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... Freescale Semiconductor, Inc. AN2344/D 6 HC908EY16 EMI Radiated Emissions Results For More Information On This Product, Figure 4. TEM CELL PCB POWER LAYER Go to: www.freescale.com MOTOROLA ...
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... A flowchart for the test software used is shown in Appendix B. MOTOROLA HC908EY16 EMI Radiated Emissions Results For More Information On This Product, Figure 5. TEM CELL PCB BOTTOM LAYER Go to: www.freescale.com AN2344/D TEM Cell Test Board Information 7 ...
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... Freescale Semiconductor, Inc. AN2344/D Analysis/Conclusions The results obtained from the radiated emissions testing are shown in Appendix A. They demonstrate that the radiated emissions from the HC908EY16 microcontroller are very low at a device level. They also confirm that there is a noticeable difference in the emissions spectrum between the external crystal and ICG configurations, with the ICG generally showing a lower emissions spectrum ...
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... TEM Cell board in place on TEM Cell, but no power applied to device MOTOROLA HC908EY16 EMI Radiated Emissions Results For More Information On This Product, Background 400 600 800 Frequency (MHz) Figure 6. Background Measurement Go to: www.freescale.com AN2344/D Appendix A: Measured Results 1000 1200 9 ...
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... Freescale Semiconductor, Inc. AN2344 -10 -15 -20 -25 -30 0 Figure 7. Device in North Orientation (External Crystal -10 -15 -20 -25 -30 0 Figure 8. Device in East Orientation (External Crystal) 10 HC908EY16 EMI Radiated Emissions Results For More Information On This Product, 0L31N_N1 200 400 600 800 ...
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... Figure 10. Device in East Orientation (ICG) MOTOROLA HC908EY16 EMI Radiated Emissions Results For More Information On This Product, 0L31N_N2 200 400 600 800 Frequency (MHz) 0L31N_E2 200 400 600 800 Frequency (MHz) Go to: www.freescale.com AN2344/D Appendix A: Measured Results 1000 1200 1000 1200 11 ...
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... Freescale Semiconductor, Inc. AN2344/D Appendix B: DUT Software Flowchart Start Disable Interrupts Initialise Clocks Timer A Test Timer B Test Port Toggle ATD Test SPI Test ESCI Test Toggle LED 12 HC908EY16 EMI Radiated Emissions Results For More Information On This Product, Initialise Clocks External EXTERNAL CRYSTAL ...
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... Set Modulo Registers to $00FF Select CH2 Buffered PWM Set PWM to 50% Start Timer RTS Figure 12. Flowchart, Page 2 Go to: www.freescale.com AN2344/D Appendix B: DUT Software Flowchart A/D Test Set Port B to Input Set Port A Bits 2,3 and 4 to Output and High Select Bus Clock Select Channel 0 ...
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... Freescale Semiconductor, Inc. AN2344/D SPI Test Select Baud Rate Enable SPI In Master Mode Clear The SPRF Flag Send 0x55 Wait Until Byte Is Recieved RTS 14 HC908EY16 EMI Radiated Emissions Results For More Information On This Product, SCI Test Enable SCI Enable Tx and Rx And Start ...
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... Freescale Semiconductor, Inc. This Page Has Been Intentionally Left Blank MOTOROLA HC908EY16 EMI Radiated Emissions Results For More Information On This Product, Go to: www.freescale.com AN2344/D Appendix B: DUT Software Flowchart 15 ...
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... Motorola and the Stylized M Logo are registered in the U.S. Patent and Trademark Office. digital dna is a trademark of Motorola, Inc. All other product or service names are the property of their respective owners. Motorola, Inc Equal Opportunity/Affirmative Action Employer. © Motorola, Inc. 2002 AN2344/D Go to: www.freescale.com ...