emc measurements of components. 2 summary 1. emc problem examples 2. em disturbance sources 3. emc...

EMC measurements of components

2

Summary

1. EMC problem examples

2. EM disturbance sources

3. EMC certification ?

4. EMC measurement for electronic systems

5. EMC measurement for integrated circuits

10 Apr 2023

3

EMC problem examples

A typical electromagnetic environment…

10 Apr 2023

4

http://www.emcs.org/acstrial/newsletters/fall04/63_67.pdf


Electromagnetic interference issues in medical devices

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

Medical device EMI problems reported

by FDA between 1979 and 1993

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.10 Apr 2023

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Electromagnetic interference issues in military systems

29th 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 of the rocket.

H.M.S. Sheffield catastrophe: “During the Falklands 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 of opportunity for the Exocet missile.”


10 Apr 2023

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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.”


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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)

FAA Aviation Safety Reporting System has reported 12 cases of interference in aircraft due to personal electronic devices since 2002.

NASA publication 1374 (1986 – 1995)


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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]


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Various disturbance sources that can affect electronic system operation

Natural sources Human activity

Intentional emission

Non intentional emissionElectrostatic discharge

EM disturbance sources

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Interferences from telecommunication systems

Fréquence (Hz)

100K 1M 10M 100M 1G 10G 100G

Radio AMRadio OC

CBTV VHF

Radio FM

RFID

TV UHF

ISM

GSMGPS

DCS

UMTS

Liaison satellite

IEEE 802.11

VHF30-300MHz

UHF300-3000MHz

SHF3-30GHz

EHF30-300GHz

HF3-30MHz

MF0.3-3MHz

Wimax

ZigBee

WiFi Gigabit

Liaison sous marine

Narrowband emission, modulated signals.

Regulation and planification of radioelectric spectrum controlled by ITU-R at international level, and by « Agence Nationale des Fréquences » (ANFR) at French level.

Radio-navigation


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Interferences from electronic systems

Parasitic noise generated by the activity (switching) of any electrical or electronic devices

The noise is usually impulse type broadband noise.

Example : Radiated emission from a 16 bit microcontroller (quartz freq = 8 MHz)


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The EM environment according to ITU-R 372-8

Ambient field levels defined from EM survey in 70’s.

Recent surveys show a 20 – 40 dB increase in semi-enclosed environment.

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.


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The EM environment


Site Agence Nationale des Fréquences (www.anfr.fr) – outil Cartoradio.

Cha

mp

E

Etot = 4.35 V/m

Distance antenne – point de mesure = 60m

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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.

Summary

But it is a tedious task because:

Diversity in terms of electronic devices

Numerous types of disturbances (LF, HF, pulsed, modulated), numerous EM environment

Various EM coupling possibilities (conducted, radiated, near-field…)

How defining generic tests to guarantee EMC for any electronic systems in any EM environment, with an industrial realism ?

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The EMC certification

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.

CE mark

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.

Using harmonized standards adapted to the product to verify the supposition of conformity is recommended

EMC European Directive

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R&TTE European Directive

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. .

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.

R&TTE mark:

Required for all equipments under the

R&TTE directive

Warning signal for class 2 equipments (special

recommandations)10 Apr 2023

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International European

International Electrotechnical Commission(IEC)

TC77Comité International Spécial des

Perturbations Radioélectriques(CISPR)

IEC 61000-X CISPR-XX

European Commitee for Electrotechnical Standardization (CENELEC)

European Telecommunication Standards Institute

(ETSI)

EN 300XXEN 50XXXEN 55XXXEN 6XXXX

Harmonized standards


EMC normative bodies: the importance of EMC standards !

10 Apr 2023

Commercial harmonized standard (non exhaustive list !)

Basic standard(general and fundamental rules)

EN 61000-4-x(IEC61000-4-x)

EMC – Testing and measurement techniques

Generic standard(for equipments in a specific environment)

EN 61000-6-3 (IEC61000-6-3)

Generic Emission Standard, for residential, commercial and light industrial environment

EN 61000-6-1 (IEC61000-6-1)

Generic Immunity Standard, for residential, commercial and industrial environment

Product standard(for a specific product family)

EN 55022(CISPR22)

Information technology equipment (ITE)

EN 55014(CISPR14)

Household appliances, electric tools and similar apparatus

EN 55012(CISPR12)

Vehicles, boats and internal combustion engines

EN 330220 (ETSI 330 220)

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 mW;

EN 330330(ETSI 300330-1)

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


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Automotive, military, aerospace and railway industries have developed their own EMC standards.

Applications Standard references

Automotive ISO 7637, ISO 11452, CISPR 25, SAE J1113

Aerospace DO-160, ED-14

Military MIL-STD-461D, MIL-STD-462D, MIL-STD-461E

Railway EN 50121

Commercial harmonized standard (non exhaustive list !)


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Case study 1


You want to place on the European market a ventilator for domestic

installation. It is supplied by mains (220 V).

Which EMC standard(s) should you follow ? What tests should you

conduct for the EMC certification ?

10 Apr 2023

Application of EN55014-1 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 (EN55015), radio

receivers (EN55025), gaming machine

(EN55022).


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Case study 1

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Case study 2


Suggested emission tests:

Conducted emission 150 KHz – 30 / 300 MHz

Harmonic and flicker

Radiated emission 30 MHz – 1 GHz

Suggested immunity tests:ESD 4 KV contact / 8 KV air

EFT / burst 5/50 ns, 1 KV, 5 KHz repetition

Conducted immunity 150 KHz – 230 MHz, 3 V rms

Radiated immunity 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×

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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 mW. The emitter/receiver is an handheld device.



Case study 2

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Case study 2


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 mW” 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.

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Case study 2


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 mW)

Transient power The switching of the transmitter produces interferences in adjacent spectrum

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

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 …

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Case study 3


You are a semiconductor manufacturers and you want to sell your

integrated circuits in the European market. Your ICs are dedicated to

automotive applications.



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Case study 3


If your integrated circuits can not operate by themselves, you don’t

need EMC certification.

However, your customers will certainly push you to guarantee the low

emission and susceptibility of your devices, require measurements,

models, support….

Examples of standards providing EMC measurement for ICs:

• IEC 61967: Integrated Circuits, Measurement of Electromagnetic

Emissions, 150 kHz to 1 GHz

• IEC 62132: Integrated circuits - Measurement of electromagnetic immunity,

150 kHz to 1 GHz

• ISO11452: Road vehicles - Electrical disturbances by narrowband

electromagnetic energy - Component test methods

• ISO 7637 or IEC61000-4-2/4/5 for ESD, pulse, surge testing.

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Why EMC standard measurement methods

Check EMC compliance of ICs, equipments and systems Comparison of EMC performances between different products,

different technologies, designs, PCB routings

Improve interaction between customers and providers (same

protocols, same set-up)

EMC measurement for electronic systems

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Equipment / Device under test Coupling device

Coupling network

Antennas

Wave guide

Current clamp…

Acquisition system

Spectrum analyzer

EMI receiver

Oscilloscope

Emission measurements – General measurement set-up

Radiated or conducted coupling

50Ω adapted path

Control - Acquisition

Emission requirements verified ?

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Emission measurements – Emission spectrum

Amplitude (dBµV)

Frequency (MHz)

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Emblematic EMC equipment – Spectrum Analyzer (EMI receiver)

Frequency adjustment : Start, stop

, center

Amplitude adjustment : Level reference, dynamic.

Emission measurement requires high sensitivity and resolutionEmission measurement standards often recommend spectrum analyzer adjustment

RBW – frequency resolution, noise floor reduction

VBW – smooth display

50 Ohm input

X= frequency

Y= power (dBm, dBµV)

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Principle: based on super heterodyne receiver

tttt lorflorflorf cos2

1cos

2

1coscos

IN

fFrf

LO

fFlo

Input signal

Local oscillator

Output signalOUT

fFif Frf+Flo

ωif

MixerIF filter

OUT

fFif

IF filterA

No

RBWP = ½.A²+No.RBW

Detected power:

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Attenuator

DC blocking

Low pass filter

Gain IF

IF filter

Analog filter

Gain log

Video filter

Mixers

Local oscillator

Reference oscillator

Frequency sweep

Display

Envelope detector

Building blocks and adjustable elements:

Input signal

RBW VBWDetector

Attenuation

Fstart / Fstop

Fcenter / SpanPoint number



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Example: effect of RBW and VBW.Measurement of 100 MHz sinus.

Amplitude = 90 dBµV Amplitude = 20 dBµV

Sweep time :

RBW = 100 KHz 2.5 ms

RBW = 10 KHz 100 ms

Sweep time :

VBW = 30 KHz 100 ms

VBW = 1 KHz 980 ms



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Example: Influence of detector type (peak vs. quasi-peak vs. average).Measurement of radiated emission of a microcontroller.



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Device under testWide band

(calibrated) antenna

Power supply, DUT control

EMI receiver or spectrum analyzer)

Absorbents

R = 3 ou 10 m

1 m1 m

1 m

Faraday cage (with absorbents: semi-anechoic chamber)

(Siepel)

EN55022


Radiated emission in (semi-)Anechoic chamber (30 MHz – 1 GHz)

10 Apr 2023


E field EMI receiver

Rs =50 Ω

Optional pre-amplifier

Low loss 50 Ω cable

Bilog antenna

(or log-periodic, biconical, dipole…)

Vemi

Radiated emission in (semi-)Anechoic chamber (30 MHz – 1 GHz)

If far field and free space conditions ensured:

dBLossdBGainmdBAFmdBµVEdBµVVemi )/(/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 10 Apr 2023

Measured power Pemi

50107 Semiemi RwithdBµVVdBmP

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Example of emission measurementsConducted emission on power supply (FCC certification) – Peak detector

39


Example of emission measurements

10 Apr 2023

Radiated emission at 3 meters (FCC certification) – Peak detector


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 dB/m, and its receiving floor is -90 dBm. It is placed at 1 m of a “noisy” electronic equipment with a CE Mark.

Could you have a risk of interferences ?

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Equipment / Device under test

Coupling deviceCoupling

network

Antennas

Wave guide

Clamp…

Radiated or conducted coupling

Disturbance generation

Harmonic signal

Transients

Burst

50Ω adapted path

Failure detectionInjected level Extraction

Immunity requirements verified ?


Immunity measurements – General measurement set-up

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Immunity measurements – General test procedure for harmonic disturbance

Start

F = Fmin

P = Pmin

Increase P

Wait dwell time

Failure or P = Pmax ?

Save F and PF = Fmax ?

End

Increase FWithout EMI

With EMI Failure

Detection mask

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Device under testWide band

(calibrated) antenna

Power supply, DUT control

Absorbents

R = 3 ou 10 m

1 m1 m

1 m

Faraday cage (with absorbents: semi-anechoic chamber)

(Siepel)

Radiated immunity in (semi-)Anechoic chamber (30 MHz – 1 GHz)

Power amplifier ( > 100 W)

Signal synthesizer

Field monitoring

Typical max. RI level:

Commercial product: 3 – 10 V/m

Automotive (ISO-11452-2): 25 – 200 V/m

Military (MIL-STD461E): 20 – 200 V/m

Aeronautics (DO160-D): 8 – 800 V/m

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Injection clamp

Induced RF current

Bus, cable

Microcontroler

DUT

Failure ?

Measurement clamp

Directional coupler

Signal synthesizer

RF disturbance

LoadLISN

Induced current measurement

Interface circuit

Faraday cage

Usually, the max. current is between 50 mA and 300 mA.


Immunity measurements – Bulk current injection (BCI)

Power amplifier

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Immunity measurements – Pulse, ESD, bursts, surge…Pulse waveforms and severity levels defined by standards such as IEC61000-4-x or ISO7637

Ideal ESD waveform at 4 KV (IEC61000-4-2) (level 2)

Tr = 0.8 ns

I30 = 8 A

I60 = 4 A

Ipeak = 15 A

Ideal Fast transient / burst (IEC61000-4-4) (level 2)

Vpeak = 1 KV (on 50 Ω)

Vpeak = 1 KV (on 50 Ω)

Tr = 5 ns Repetition rate = 5 – 100 KHz

Td= 50 ns

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EMC measurement for integrated circuits

Why taking into account EMC for ICs ?

K. Armstrong, Advanced PCB design and layout for EMC

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Why testing EMC for ICs ?

Integrated circuits are often the main cause of disturbances in electronic equipment.

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:

Obtain quantitative measure of emission/immunity from ICs establishing a

uniform testing environment Qualify the low emission and high immunity performance of circuit. Optimize circuit placement, routing, filtering and decoupling components Evaluate the impact of IC redesign, technology improvement or package

modification.

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Why testing EMC for ICs ? Based on pre existing standards, such as:

CISPR 25 – Radio disturbance characteristics for the protection of receivers used

on board vehicles, boats and on devices – Limits and methods of measurements

IEC 61000-4 – Electromagnetic Compatibility (EMC) – Part 4: Testing and

measurement techniques

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:

IEC 61967:Integrated circuits -Measurement of electromagnetic

emissions, 150 kHz to 1 GHz.

IEC 62132: Integrated circuits - Measurement of electromagnetic

immunity, 150 kHz to 1 GHz.

IEC 62215: Integrated circuits – Measurement of impulse immunity

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International standards for IC emission measurement methods

IEC 61967-2

(TEM : 1GHz)

IEC 61967-2

(GTEM 18 GHz)

IEC 61967-5

(WBFC, 1 GHz)

IEC 61967-8

(IC-Stripline, 3/6 GHz)

IEC 61967-3

(Near field scan, 1/5GHz)

IEC 61967-6

(Magnetic field probe, 1GHz)

IEC 61967-4

(1/150 ohm, 1 GHz)

IEC 61967-7

(Mode stirred chamber, 1 GHz)

Appareil de mesure 50

ohms Câble coaxial Z0=50Ω

Appareil de mesure 50Ω Conducted method

Radiated method TEM Cell improvemnt

Investigation method


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IC Conducted emission

Osc

illat

or

Digital Core

I/O

Driver

VddCore

Vdd osc

PCB line

Load

Load

Integrated circuit

Icore(t)

Iosc(t)

VE/S(t)

Vdriver(t)

Two noise sources: internal activity (power supply noise) and I/O

switching (Simultaneous Switching Noise, I/O line excitation)

Characterization of transient current and voltage induced by ICs.

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« Local » ground

IC Conducted emission - IEC 61967-4 –1 ohm / 150 ohms method

ICPCB

Decoupling

RF current Conducted emission is produced

by RF current induced by IC

activity.

The current induced voltage

bounces along power distribution

network and radiated emission.

The « 1 ohm » method aims at measuring the RF current flowing from circuit Vss pin(s) to the ground reference.

2RF

A

IV

Vdd

« Global » ground

Spectrum analyzer

1 Ω

49 Ω

IRF

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IC Conducted emission - IEC 61967-4 –1 ohm / 150 ohms method

I/O buffer

RF current

RF current

External load

I/O switching is a major contributor to conducted emission.

They induced voltage fluctuation along power supply and I/O

lines.

The « 150 ohms » method aims at measuring the RF voltage induced at one or several IC output.

Vdd

PCB

Decoupling

51 Ω

120 Ω 6.8 nFSpectrum analyzer

150 Ω matching network

)150(

17.0

KHzabove

VV RFA

VRF VA


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IC current extraction from 1 Ω probe measurement

dsPIC33F: measurement in time domain and frequency of the voltage

across the 1 Ω probe proportional to the IC current.


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IC Radiated emission - IEC 61967-2 – TEM cell

TEM cell (SAE J1752/3)

IC under test

Emission spectrum

Spectrum analyzer

Pre-ampli 20-30 dB

Test board

Relation between the voltage measured by the spectrum analyzer and the radiated emission from the circuit

50 ohm


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TEM cell – EM field inside the waveguide

septum

Aperture for DUT

Port1 Port2

50 Ω 50 Ω

y

z

y

x

Tapered transition

Tapered transition

E

H

O Field repartition:

Quasi homogeneous field

R.J. Spiegel, and al.,“A Method for Calculating Electric and Magnetic Fields in TEM Cells at ELF”, IEEE Trans. on EMC, Nov. 1987

o TEM propagation

mode up to 1 GHz

o |E/H| = 377 Ω

W = 15 cm, T = 9 cm, Wsept = 10 cm, V = 1 V, y = 8 cmWsept

T

W


56

TEM cell – Field coupling with a DUT

Example: coupling with a 50Ω microstrip line

Dimensions of the microstrip: W = 2.5 mm, L = 75 mm, h = 1.6 mm, epsr = 4.5

septumPort150 Ω load

50 Ω load

Port2 VNANear end Far

end Appearance of non TEM propag. mode

+ 20 dB/dec.


The magnetic field coupling

depends of the orientation of

the line in the TEM cell.

57

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 / 18GHz)

IEC 62132-8

(IC-Stripline, 3/6 GHz)

IEC 62132-5

(WBFC, 1 GHz)

IEC 62132-6

(LIHA, 10GHz)

IEC 62132-9

(Near-field scan, 1/5 GHz)

IEC 62132-7

(Mode stirred chamber, 1 GHz)

Conducted methods Radiated methods

TEM cell improvement

Investigation method


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Victim circuit

Electronic equipment

Cables

PCB

Radiated disturbances

Induced conducted disturbances

Vs

Zs

Zc, Td ZL

Equivalent Thevenin generator of RF

disturbancesCables, PCB lines

Input impedance of victim circuit

Conducted immunity

Applying conducted disturbances directly to IC pin ?

58


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Conducted immunity - IEC 62132-4 – Direct Power Injection (DPI)

DPI Capacitor ( 1 – 10 nF)

Decoupling network

Chip under test

Pforw Prefl

Directional coupler

Signal Synthesizer

Amplifier

Failure detection

• Oscilloscope• Acquisition card

Susceptibility threshold

> 400 Ω

Test on 1 pin

Individual test of each sensitive IC pin.


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60


0

5

10

15

20

25

30

35

1 10 100 1000

Forw

ard

pow

er (d

Bm)

Frequency (MHz)

Forward power limit

Example : DPI test on the power supply of an RF device

Simple, repeatable, low power measurement

IC prequalification test


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Class Fwd Power (dBm - RMS)

Voltage (V) (across 50 Ω)

I/O type – protection level

1 30 - 37 10 - 22 Low filtering, pin connected to long cable harness (power circuit)

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

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Case study – Starcore EMC testing 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 66MHz data/address

ADC In[0..3] 4 analog inputs (12 bit resolution)

CAN Tx CAN interface (high power, 1MHz)

CAN Rx CAN interface (high power, 1MHz)

XTL_1, XTL_2 Quartz oscillator 16MHz

CAPA PLL external capacitance

RESET Reset microcontroller10 Apr 2023

emc measurements of components. 2 summary 1. emc problem examples 2. em disturbance sources 3. emc...

Documents

em disturbances

em survey

emc certification

cases of interference

various disturbance

personal electronic

emc measurements of

parasitic emission