EMC measurements of components Summary 1 EMC problem
EMC measurements of components
Summary 1. EMC problem examples 2. EM disturbance sources 3. EMC certification ? 4. EMC measurement for electronic systems 5. EMC measurement for integrated circuits 2 February 21
EMC problem examples A typical electromagnetic environment… 3 February 21
EMC problem examples Electromagnetic interference issues in medical devices n Medical device EMI problems reported by FDA between 1979 and 1993 EMI types Reported cases Devices Conducted interference 20 (1 death) Cardiac monitor, infusion device, defibrilator… Radiated interference 55 (4 deaths) Pacemaker, ventilator, cardiac monitor LF magnetic field 6 (1 death) Respirator, pacemaker ESD 10 Respirator, infusion pump n http: //www. emcs. org/acstrial/new sletters/fall 04/63_67. pdf 405 suspected EMI problems reported by FDA between 1994 and 2005, with 6 deaths, 170 injuries and 167 malfunctions. 72 % of cases concern implantable devices. 4 February 21
EMC problem examples Electromagnetic interference issues in military systems 29 th July 1967 : accident of the American aircraft carrier USS Forrestal. The accidental launching of a rocket blew gas tank and weapon stocks, killing 135 persons and causing damages which needed 7 month reparations. Investigations showed that a radar induced on plane wiring a sufficient parasitic voltage to trigger the launching H. M. S. Sheffield catastrophe: “During the Falklands of the rocket. War, the British Ship H. M. S Sheffield sank after being hit by an Exocet missile. Despite the Sheffield having the most sophisticated antimissile defense system available, the system created EMI to radiocommunications to and among the contingent of Harrier jets assigned to the ship. While the Harriers took off, the missile defense was disengaged to allow communications with the jets and provided a window 5 of opportunity for the Exocet missile. ” February 21
EMC problem examples Electromagnetic interference issues in automotive Interference Technology – October 2011 Mercedez-Benz case: “During the early years of ABS, Mercedez-Benz automobiles equipped with ABS had severe braking problems along a certain stretch of the German autobahn. The brakes were affected by a near-by-near radio transmitter as drivers applied them on the curved section of highway. The near-term solution was to a erect a mesh screen along the roadway to attenuate the EMI. This enabled the brakes to function properly when drivers applied them…. Eventually, automobile ABS was qualified by EMI testing prior to procurement. ” 6 February 21
EMC problem examples Electromagnetic interference issues in aviation « Disturbances of flight instruments causing trajectory deviations appear when one or several passengers switch on electronic devices. » (Air et Cosmos, April 1993) NASA publication 1374 (1986 – 1995) FAA Aviation Safety Reporting System has reported 12 cases of interference in aircraft due to personal electronic devices since 2002. 7 February 21
EMC problem examples Electromagnetic interference issues in space aircraft Vacuum cleaner incident: “During a Spacelab mission in 1985, the crew decided to use the middeck vacuum cleaner instead of the one in the lab. Switching the middeck vacuum on caused the voltage to drop and the Remote Acquisition Unit to shut off. In preflight EMI tests, the vacuum cleaner had not been tested and should not have been used in the lab. This case shows how careful and attentive one must when dealing with EMC. ” [Nasa Publication 1374] 8 February 21
EM disturbance sources Various disturbance sources that can affect electronic system operation Human activity Natural sources Intentional emission Electrostatic discharge 9 February 21 Non intentional emission
EM disturbance sources Interferences from telecommunication systems Radionavigatio n ü Narrowband emission, modulated signals. ü Regulation and planification of radioelectric spectrum controlled by ITU-R at international level, and by « Agence Nationale des Fréquences » (ANFR) at French level. 10 February 21
EM disturbance sources Interferences from electronic systems ü Parasitic noise generated by the activity (switching) of any electrical or electronic devices ü The noise is usually impulse type broadband noise. ü Example : Radiated emission from a 16 bit microcontroller (quartz freq = 8 MHz) 11 February 21
EM disturbance sources The EM environment according to ITU-R 372 -8 ü Ambient field levels defined from EM survey in 70’s. ü Recent surveys show a 20 – 40 d. B increase in semi-enclosed environment. ü Example: Survey of the average level of electric field in Canada during the 90’s in urban and suburban environment: between 1 and 20 V/m. 12 February 21
EM disturbance sources The EM environment ü Site Agence Nationale des Fréquences (www. anfr. fr) – outil Cartoradio. Champ E Distance antenne – point de mesure = 60 m Etot = 4. 35 V/m 13 February 21
Summary § EM disturbances can induce major failures in electronic systems. § The parasitic emission and susceptibility to EM disturbances must be tested to ensure electromagnetic compatibility of an electronic systems within a nominal environment. § But it is a tedious task because: ü Diversity in terms of electronic devices ü Numerous types of disturbances (LF, HF, pulsed, modulated), numerous EM environment ü Various EM coupling possibilities (conducted, radiated, nearfield…) How defining generic tests to guarantee EMC for any electronic systems in any EM environment, with an industrial realism ? 14 February 21
The EMC certification EMC European Directive ü The European directive 89/336/EEC (1996) and then 2004/108/EC (2004) requires that all « electrical apparatus » placed on the European market : § Do not produce electromagnetic interferences able to disturb radio or telecom equipments , and the normal operation of all equipments § Have a sufficient immunity level to electromagnetic interferences to prevent any degradation of the normal operation. ü All manufacturers of « electrical apparatus » must certify that the directive is supposed respected by delivering a declaration of conformity and placing a CE mark on the product. CE mark ü Using harmonized standards adapted to the product to verify the supposition of conformity is recommended 15 February 21
The EMC certification R&TTE European Directive ü The European directive 99/5/EC (1999) Radio & Telecommunications Terminal Equipment which is applied to all telecom and radio equipments emitting on the band 9 KHz – 3000 GHz replace the EMC directive. . ü R&TTE requires that telecom and radio equipments placed on the European market: : § Comply to safety constraints given by the Low Voltage directive (73/23/EEC) (e. g. the limit of EM exposure for persons) and the EMC constraints given by the EMC directive 2004/108/EC. § Radio equipments use spectral resources dedicated for terrestrial and spatial communications without generating any interferences. ü R&TTE mark: Required for all equipments under the R&TTE directive 16 February 21 Warning signal for class 2 equipments (special recommandations)
The EMC certification EMC normative bodies: the importance of EMC standards ! International European International Electrotechnical Commission(IEC) TC 77 European Commitee for Electrotechnical Standardization European Telecommunication Standards Institute (CENELEC) (ETSI) Comité International Spécial des Perturbations Radioélectriques(CISPR) Harmonized standards IEC 61000 -X EN 50 XXX EN 55 XXX EN 6 XXXX CISPR-XX 17 February 21 EN 300 XX
The EMC certification Commercial harmonized standard (non exhaustive list !) Basic standard (general and fundamental rules) Generic standard (for equipments in a specific environment) Product standard (for a specific product family) EN 61000 -4 -x (IEC 61000 -4 -x) EMC – Testing and measurement techniques EN 61000 -6 -3 (IEC 61000 -6 -3) Generic Emission Standard, for residential, commercial and light industrial environment EN 61000 -6 -1 (IEC 61000 -6 -1) Generic Immunity Standard, for residential, commercial and industrial environment EN 55022 (CISPR 22) Information technology equipment (ITE) EN 55014 (CISPR 14) Household appliances, electric tools and similar apparatus EN 55012 (CISPR 12) Vehicles, boats and internal combustion engines EN 330220 (ETSI 330 220) EN 330330 (ETSI 300330 -1) Electromagnetic compatibility and radio spectrum matters (ERM); Short Range Devices (SRD); Radio equipment to be used in the 25 MHz to 1 000 MHz frequency range with power levels ranging up to 500 m. W; Electromagnetic compatibility and radio spectrum matters (ERM); Short Range devices (SRD); Radio equipment to be used in the frequency range 9 KHz to 25 MHz and inductive loop systems in the frequency range 9 KHz to 30 MHz 18 February 21
The EMC certification Commercial harmonized standard (non exhaustive list !) ü Automotive, military, aerospace and railway industries have developed their own EMC standards. Applications Standard references Automotive ISO 7637, ISO 11452, CISPR 25, SAE J 1113 Aerospace DO-160, ED-14 Military MIL-STD-461 D, MIL-STD-462 D, MILSTD-461 E Railway EN 50121 19 February 21
The EMC certification Case study 1 n You want to place on the European market a ventilator for domestic installation. It is supplied by mains (220 V). n Which EMC standard(s) should you follow ? What tests should you conduct for the EMC certification ? 20 February 21
The EMC certification Case study 1 n Application of EN 55014 -1 and 2: “Electromagnetic compatibility – Requirements for household appliances, electric tools and similar apparatus” – Part 1 = Emission, Part 2 = Immunity : § Any domestic electric/electronic equipments, toys, electric tool supplied under 250 V (monophase) (motors, heat elements, thermostats …) § Except light modules (EN 55015), radio receivers (EN 55025), gaming machine (EN 55022). 21 February 21
The EMC certification Case study 2 n Suggested emission tests: Conducted emission 150 KHz – 30 / 300 MHz Harmonic and flicker Radiated emission n 30 MHz – 1 GHz Suggested immunity tests: ESD EFT / burst Conducted immunity Radiated immunity 4 KV contact / 8 KV air 5/50 ns, 1 KV, 5 KHz repetition 150 KHz – 230 MHz, 3 V rms 80 – 1000 MHz, 3 V/m, modulation AM 1 KHz 80% Surge 1 KV 1. 2/50 µs pulse on power Voltage dips and interruptions 40 % variations of the power supply, repeated 5× 22 February 21
The EMC certification Case study 2 n You want to place on the European market a radio emitter/receiver for remote control application in residential environment. The radio emitter use the ISM band around 434 MHz. Its maximum radiated power is limited to 500 m. W. The emitter/receiver is an handheld device. n Which EMC standard(s) should you follow ? What tests should you conduct for the EMC certification ? 23 February 21
The EMC certification Case study 2 n The harmonized standard EN 300220: “Electromagnetic compatibility and radio spectrum matters (ERM); Short Range devices (SRD); Radio equipment to be used in the 25 MHz to 1000 MHz frequency range with power levels ranging up to 500 m. W” is adapted to short range devices : § either with a Radio Frequency (RF) output connection and/or with an integral antenna; § for alarms, identification, telecommand, telemetry, etc. , applications; § with or without speech. § It covers fixed stations, mobile stations and portable stations, all types of modulation. 24 February 21
The EMC certification Case study 2 n List of suggested tests: Frequency error or drift Does the carrier frequency remains stable? Effective radiated power The radiated power must not exceed a max. level (< 500 m. W) Transient power Adjacent channel power The power transmitted in adjacent band must be limited. Spurious emissions Parasitic emissions from the emitter and receiver between 9 KHz and ? ? Must be limited. Frequency stability under low voltage conditions n The switching of the transmitter produces interferences in adjacent spectrum The emission from the transmitter must remain stable even in extreme low power conditions. Duty cycle The manufacturer must indicate the duty cycle of the equipment Blocking or desensitization Capability of the receiver to receive a wanted signal in presence of unwanted signal Some ESD tests should be also done … 25 February 21
The EMC certification Case study 3 n You are a semiconductor manufacturers and you want to sell your integrated circuits in the European market. Your ICs are dedicated to automotive applications. n Which EMC standard(s) should you follow ? What tests should you conduct for the EMC certification ? 26 February 21
The EMC certification Case study 3 n If your integrated circuits can not operate by themselves, you don’t need EMC certification. n However, your customers will certainly push you to guarantee the low emission and susceptibility of your devices, require measurements, models, support…. n Examples of standards providing EMC measurement for ICs: • IEC 61967: Integrated Circuits, Measurement of Electromagnetic Emissions, 150 k. Hz to 1 GHz • IEC 62132: Integrated circuits - Measurement of electromagnetic immunity, 150 k. Hz to 1 GHz • ISO 11452: Road vehicles - Electrical disturbances by narrowband electromagnetic energy - Component test methods • ISO 7637 or IEC 61000 -4 -2/4/5 for ESD, pulse, surge testing. 27 February 21
EMC measurement for electronic systems Why EMC standard measurement methods n Check EMC compliance of ICs, equipments and systems n Comparison of EMC performances between different products, different technologies, designs, PCB routings n Improve interaction between customers and providers (same protocols, same set-up) 28 February 21
EMC measurement for electronic systems Emission measurements – General measurement set-up Control - Acquisition Radiated or conducted coupling Acquisition system 50Ω adapted path Equipment / Device under test Coupling device ü Coupling network ü Antennas ü EMI receiver ü Oscilloscope ü Wave guide ü Current clamp… Emission requirements verified ? 29 ü Spectrum analyzer February 21
EMC measurement for electronic systems Emission measurements – Emission spectrum Amplitude (d. BµV) Frequency (MHz) 30 February 21
EMC measurement for electronic systems Emblematic EMC equipment – Spectrum Analyzer (EMI receiver) Frequency adjustment : Start, stop , center Y= power (d. Bm, d. BµV) RBW – frequency resolution, noise floor reduction 50 Ohm input X= frequency VBW – smooth display n. Emission measurement requires high sensitivity and resolution n. Emission measurement standards often recommend spectrum analyzer adjustment 31 February 21 Amplitude adjustment : Level reference, dynamic.
EMC measurement for electronic systems Emblematic EMC equipment – Spectrum Analyzer (EMI receiver) n Principle: based on super heterodyne receiver IN Input signal Mixe r OUT f Frf Local LO oscillator Flo Output signal IF filter Fif Frf+F f lo f OUT IF A filter RBW No Fif ωif Detected power: f 32 P = ½. A²+No. RBW February 21
EMC measurement for electronic systems Emblematic EMC equipment – Spectrum Analyzer (EMI receiver) n. Building blocks and adjustable elements: Input Attenuatio n signal Attenuator DC blocking Mixers Low pass filter Gain IF RB IF filter W Analog filter Local oscillator Frequency sweep Fstart / Fstop Fcenter / Span Point number Display Reference oscillator 33 Gain log Detecto Envelope r VB detector Video W filter February 21
EMC measurement for electronic systems Emblematic EMC equipment – Spectrum Analyzer (EMI receiver) n. Example: effect of RBW and VBW. n. Measurement of 100 MHz sinus. Amplitude = 90 d. BµV Sweep time : RBW = 100 KHz 2. 5 ms RBW = 10 KHz 100 ms Amplitude = 20 d. BµV 34 Sweep time : VBW = 30 KHz 100 ms VBW = 1 KHz 980 ms February 21
EMC measurement for electronic systems Emblematic EMC equipment – Spectrum Analyzer (EMI receiver) n. Example: Influence of detector type (peak vs. quasi-peak vs. average). n. Measurement of radiated emission of a microcontroller. 35 February 21
EMC measurement for electronic systems Radiated emission in (semi-)Anechoic chamber (30 MHz – 1 GHz) EN 55022 (Siepel) Absorbents 1 m Wide band (calibrated) antenna EMI receiver or spectrum analyzer) Device under test 1 m Faraday cage (with absorbents: semianechoic chamber) R = 3 ou 10 m 1 m 36 Power supply, DUT control February 21
EMC measurement for electronic systems Radiated emission in (semi-)Anechoic chamber (30 MHz – 1 GHz) If far field and free space conditions ensured: Optional pre-amplifier Low loss 50 Ω cable Vemi E field EMI receiver Rs =50 Ω Bilog antenna (or log-periodic, biconical, dipole…) Measured power Pemi AF = Antenna factor (from calibration) The E field varies in 1/r with the distance r (the radiated power in 1/r²) possible extrapolation of field intensity. 37 February 21
EMC measurement for electronic systems Example of emission measurements Conducted emission on power supply (FCC certification) – Peak detector 38 February 21
EMC measurement for electronic systems Example of emission measurements Radiated emission at 3 meters (FCC certification) – Peak detector 39 February 21
EMC measurement for electronic systems Does EMC certification cancel the interference risks? Let’s consider a radio receiver (such as a mobile phone). We suppose that it operates at 900 MHz, its antenna has an antenna factor of 29 d. B/m, and its receiving floor is -90 d. Bm. It is placed at 1 m of a “noisy” electronic equipment with a CE Mark. Could you have a risk of interferences ? 40 February 21
EMC measurement for electronic systems Immunity measurements – General measurement set-up Disturbance generation 50Ω adapted path ü Harmonic signal ü Transients ü Burst Failure detection Injected level Extraction Radiated or conducted coupling Coupling device ü Coupling network Equipment / Device under test ü Antennas ü Wave guide ü Clamp… Immunity requirements verified ? 41 February 21
EMC measurement for electronic systems Immunity measurements – General test procedure for harmonic disturbance Start F = Fmin P = Pmin Increase P Increase F Without EMI Wait dwell time Detection mask Failure or P = Pmax ? F = Fmax ? Save F and P With EMI End 42 February 21 Failure
EMC measurement for electronic systems Radiated immunity in (semi-)Anechoic chamber (30 MHz – 1 GHz) Typical max. RI level: Commercial product: 3 – 10 V/m Automotive (ISO-11452 -2): 25 – 200 V/m Military (MIL-STD 461 E): 20 – 200 V/m Aeronautics (DO 160 -D): 8 – 800 V/m (Siepel) Field monitoring Absorbents Signal synthesizer 1 m Power amplifier ( > 100 W) Wide band (calibrated) antenna Device under test 1 m Faraday cage (with absorbents: semianechoic chamber) R = 3 ou 10 m 1 m 43 Power supply, DUT control February 21
EMC measurement for electronic systems Immunity measurements – Bulk current injection (BCI) Signal synthesizer Power amplifier RF disturbance Directional coupler Loa d. LIS N Bus, cable Injection clamp Induced RF current Induced current measurement Failure ? DUT Interface Microcontroler Measureme circuit nt clamp Faraday cage è Usually, the max. current is between 50 m. A and 300 m. A. 44 February 21
EMC measurement for electronic systems Immunity measurements – Pulse, ESD, bursts, surge… n. Pulse waveforms and severity levels defined by standards such as IEC 61000 -4 -x or ISO 7637 Ideal Fast transient / burst (IEC 61000 -4 -4) (level 2) Ideal ESD waveform at 4 KV (IEC 61000 -4 -2) (level 2) Ipeak = 15 A Td= 50 ns Tr = 5 ns I 30 = 8 A I 60 = 4 A Tr = 0. 8 ns 45 February 21 Vpeak = 1 KV (on 50 Ω) Repetition rate = 5 – 100 KHz Vpeak = 1 KV (on 50 Ω)
EMC measurement for integrated circuits Why taking into account EMC for ICs ? K. Armstrong, Advanced PCB design and layout for EMC 46 February 21
EMC measurement for integrated circuits Why testing EMC for ICs ? n Integrated circuits are often the main cause of disturbances in electronic equipment. n In recent years, there has been a strong demand for simple, reliable and standardized measurement methods focusing only on integrated circuits that electronic system designers could use to: è Obtain quantitative measure of emission/immunity from ICs establishing a uniform testing environment è Qualify the low emission and high immunity performance of circuit. è Optimize circuit placement, routing, filtering and decoupling components è Evaluate the impact of IC redesign, technology improvement or package modification. 47 February 21
EMC measurement for integrated circuits Why testing EMC for ICs ? n Based on pre existing standards, such as: n è CISPR 25 – Radio disturbance characteristics for the protection of receivers used on board vehicles, boats and on devices – Limits and methods of measurements è IEC 61000 -4 – Electromagnetic Compatibility (EMC) – Part 4: Testing and measurement techniques è ISO 11452 part 1 to 7, Road vehicles – Electrical disturbances by narrow band radiated electromagnetic energy – Component test methods Measurement methods for EMC of Ics proposed by IEC: è IEC 61967: Integrated circuits -Measurement of electromagnetic emissions, 150 k. Hz to 1 GHz. è IEC 62132: Integrated circuits - Measurement of electromagnetic immunity, 150 k. Hz to 1 GHz. è IEC 62215: Integrated circuits – Measurement of impulse immunity 48 February 21
EMC measurement for integrated circuits International standards for IC emission measurement methods IEC 61967 -2 (TEM : 1 GHz) IEC 61967 -2 (GTEM 18 GHz) IEC 61967 -5 (WBFC, 1 GHz) Radiated method IEC 61967 -3 (Near field scan, 1/5 GHz) IEC 61967 -8 (IC-Stripline, 3/6 GHz) TEM Cell improvemnt IEC 61967 -6 (Magnetic field probe, 1 GHz) IEC 61967 -4 (1/150 ohm, 1 GHz) Conducted method Investigation method 49 February 21 IEC 61967 -7 (Mode stirred chamber, 1 GHz)
EMC measurement for integrated circuits IC Conducted emission Vdd. Core Icore(t ) Integrate d circuit Digital Core Vdd osc Oscillat or Iosc(t) I/O VE/S(t ) Load Drive r PCB line Vdriver(t ) n Two noise sources: internal activity (power supply noise) and I/O switching (Simultaneous Switching Noise, I/O line excitation) n Characterization of transient current and voltage induced by ICs. 50 February 21 Load
EMC measurement for integrated circuits IC Conducted emission - IEC 61967 -4 – 1 ohm / 150 ohms method Vdd RF current PCB n Conducted emission is produced by RF current induced by IC activity. n The current induced voltage bounces along power distribution network and radiated emission. IC Decoupling « Local » ground 49 Ω 1 Ω « Global » ground Spectrum analyzer IRF The « 1 ohm » method aims at measuring the RF current flowing from circuit Vss pin(s) to the ground reference. 51 February 21
EMC measurement for integrated circuits IC Conducted emission - IEC 61967 -4 – 1 ohm / 150 ohms method n I/O switching is a major contributor to conducted emission. n They induced voltage fluctuation along power supply and I/O lines. Vdd RF current Decoupling 150 Ω matching network I/O buffer 120 Ω External VRF load PCB 6. 8 n. F 51 Ω Spectrum analyzer VA RF current The « 150 ohms » method aims at measuring the RF voltage induced at one or several IC output. 52 February 21
EMC measurement for integrated circuits IC current extraction from 1 Ω probe measurement n ds. PIC 33 F: measurement in time domain and frequency of the voltage across the 1 Ω probe proportional to the IC current. 53 February 21
EMC measurement for integrated circuits IC Radiated emission - IEC 61967 -2 – TEM cell IC under test Spectrum analyzer 50 ohm Test board TEM cell (SAE J 1752/3) Pre-ampli 2030 d. B Emission spectrum Relation between the voltage measured by the spectrum analyzer and the radiated emission from the circuit 54 February 21
EMC measurement for integrated circuits TEM cell – EM field inside the waveguide y Tapered transition Aperture transition for DUT Port 1 Port 2 50 Ω septu m Field repartition: R. J. Spiegel, and al. , “A Method for Calculating Electric and Magnetic Fields in TEM Cells at ELF”, IEEE Trans. on EMC, Nov. 1987 W E 50 Ω T z n y H O W = 15 cm, T = 9 cm, Wsept = 10 cm, V = 1 V, y = 8 cm Quasi homogeneous field 55 Wsept x o TEM propagation mode up to 1 GHz o |E/H| = 377 Ω
EMC measurement for integrated circuits TEM cell – Field coupling with a DUT n Example: coupling with a 50Ω microstrip line n Dimensions of the microstrip: W = 2. 5 mm, L = 75 mm, h = 1. 6 mm, epsr = 4. 5 VNA Port 1 n Port 2 Near end Far end septu m 50 Ω load Appearance of non TEM propag mode The magnetic field coupling depends of the orientation of the line in the TEM cell. + 20 d. B/dec. 56
EMC measurement for integrated circuits International standards for IC susceptibility measurement methods IEC 62132 -3 (BCI, 1 GHz) IEC 62132 -4 (DPI : 1 GHz) IEC 62132 -2 (TEM - GTEM : 1 / 18 GHz) Conducted methods IEC 62132 -5 (WBFC, 1 GHz) Radiated methods IEC 62132 -6 (LIHA, 10 GHz) IEC 62132 -9 (Near-field scan, 1/5 GHz) Investigation method 57 February 21 IEC 62132 -8 (IC-Stripline, 3/6 GHz) TEM cell improvement IEC 62132 -7 (Mode stirred chamber, 1 GHz)
EMC measurement for integrated circuits Conducted immunity n Applying conducted disturbances directly to IC pin ? Electronic equipment Radiated disturbances Victim circuit Cables PCB Induced conducted disturbances Equivalent Thevenin generator of RF disturbances Zs Vs Cables, PCB lines Zc, Td 58 58 ZL February 21 Input impedance of victim circuit
EMC measurement for integrated circuits Conducted immunity - IEC 62132 -4 – Direct Power Injection (DPI) n Individual test of each sensitive IC pin. Signal Synthesizer Amplifier Decoupling network Pforw Prefl Directional coupler Test on 1 pin Failure detection > 400 Ω DPI Capacitor ( 1 – 10 n. F) Chip under test • Oscilloscope • Acquisition card Susceptibility threshold 59 February 21
EMC measurement for integrated circuits Conducted immunity - IEC 62132 -4 – Direct Power Injection (DPI) Example : DPI test on the power supply of an RF device Forward power limit è Simple, repeatable, low power measurement è IC prequalification test 60 February 21
EMC measurement for integrated circuits Conducted immunity - IEC 62132 -4 – Direct Power Injection (DPI) Class Fwd Power (d. Bm - RMS) Voltage (V) I/O type – protection level (across 50 Ω) 1 30 - 37 10 - 22 2 20 – 27 3 – 7 Short connections, low filtering (signal conditioning, communication line driver) 3 10 - 17 1 - 2 No direct connection with the environment Low filtering, pin connected to long cable harness (power circuit) 61 February 21
EMC measurement for integrated circuits Case study – Starcore EMC testing n n The Starcore is 16 -bit micro-controller used in automotive industry: • 16 bit MPU with 16 MHz external quartz, on-chip PLL providing internal 133 MHz operating clock • 128 Kb RAM, 3 general purpose ports (A, B, C, 8 bits), 4 analog inputs 12 bits, CAN interface Prepare an EMC test plan: conducted emission (1 /150 Ω) and susceptibility test (DPI) SIGNAL Description VDD Positive supply VSS Logic Ground VDD_OSC Oscillator supply VSS_OSC Oscillator ground PA[0. . 7] Data port A (programmable drive) PB[0. . 7] Data port B (programmable drive) PC[0. . 7] Data port C (programmable drive) external 66 MHz data/address ADC In[0. . 3] 4 analog inputs (12 bit resolution) CAN Tx CAN interface (high power, 1 MHz) CAN Rx CAN interface (high power, 1 MHz) XTL_1, XTL_2 Quartz oscillator 16 MHz CAPA PLL external capacitance RESET Reset microcontroller 62 February 21
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