EMI Suppression Filters for Digital Equipment
56Pages

!Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. C33E.pdf 04.5.12 Noise Suppression by EMIFILr Digital Equipment Application Manual Murata Manufacturing Co., Ltd. Cat.No.C33E

!Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. Introduction Because the process of EMI noise emission, conduction and radiation from electronic circuits is complicated, it is very difficult for us to suppress such EMI noise. To improve noise suppression efficiency, we must thoroughly...

!Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. C33E.pdf 04.5.12 1 Noise Sources in Digital Equipment 1 The electronic circuits that may raise EMI noise problems use many ICs, which makes the process of EMI noise emission very complicated. To explain the EMI noise phenomena simply, this...

C33E.pdf 04.5.12 !Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. Noise Sources in Digital Equipment 1 1. Digital Signals and Harmonic Components !Digital Signals Higher Harmonics Analysis Model 1 T : Cycle Time t =d : Duty Radio T 1 t T ƒ(x)=d(1+2A1coswot+2A2cos2wot+...) sink π d...

C33E.pdf 04.5.12 !Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. 1 Noise Sources in Digital Equipment Example of Digital's Spectrum Measurement !Test Circuit VCC (+5V) CERALOCK® 16MHz Measurement Point High GND IC1 : HCU04 < Signal Waveform > IC2 : HC04 IC3 : HC00 < Signal Spectrum > 120...

C33E.pdf 04.5.12 !Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. Noise Sources in Digital Equipment Power supply noise is considered as another cause of EMI noise emission from electronic circuits. Digital IC's use DC power supplies, and the DC current on the digital IC's power supply...

C33E.pdf 04.5.12 !Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. 1 Noise Sources in Digital Equipment 2. Radiated Noise from Digital Circuit Boards !Test Circuit VCC (+5V) CERALOCK® 16MHz GND IC2 : HC04 IC1 : HCU04 CERALOCK® 10 !Board Layout Entirely grounded IC1 (HCU04) 17.5 (in cm)...

C33E.pdf 04.5.12 !Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. Noise Sources in Digital Equipment !Test Circuit VCC (+5V) CERALOCK® 16MHz 1 High GND IC2 : HC04 IC1 : HCU04 IC3 : HC00 !Board Layout 3.8 Signal Pattern 10 0.3 IC1 (HCU04) 1.7 CERALOCK® IC3 (HC00) 4.2 10 IC2 (HC04) Now we...

C33E.pdf 04.5.12 !Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. 1 Noise Sources in Digital Equipment Effect of EMI Suppression Filter !Test Circuit VCC (+5V) CERALOCK® 16MHz NFW31SP506X1E (cut-off frequency 50MHz) High 30Ω GND IC2 : HC04 IC1 : HCU04 IC3 : HC00 !Board Layout 3.8 Signal...

C33E.pdf 04.5.12 !Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. Noise Sources in Digital Equipment 1 3. Radiated Noise from Cables !Test Circuit 1 10cm Cable VCC (+5V) CERALOCK® 16MHz Open GND IC2 : HC04 IC1 : HCU04 IC3 : HC00 !Board Layout 3.8 Open 10 IC3 (HC00) 0.3 IC1 (HCU04) 1.7...

C33E.pdf 04.5.12 !Note Please read rating and !CAUTION (for storage, operating, rating, soldering, mounting and handling) in this PDF catalog to prevent smoking and/or burning, etc. This catalog has only typical specifications. Therefore, you are requested to approve our product specifications or to transact the approval sheet for product specificaions before ordering. 1 Noise Sources in Digital Equipment Example of Suppressing Radiated Noise from Cable (1) 10cm Cable VCC (+5V) CERALOCK® 16MHz NFW31SP506X1E (cut-off frequency 50MHz) Open 30Ω GND IC1 : HCU04 IC2 : HC04 IC3 : HC00 !Board...