The contributions of EMCMCC

The contributions of EMCMCC towards research and developments.

last updated on 01/06/2017


Dynamic Behavior Model for SEED Analysis; Extraction using Surface Response Modelling

ABSTRACT: System Efficient ESD Design (SEED) requires dynamic behavior models from the devices and circuitry used along the protection chain, typically from the discharge point of entry at the PCB boundary i.e. connector up to the circuits on-chip to be protected. In-between this path there may be external ESD protection i.e. voltage clamping together with parasitic layout effects, interconnect path delay with specific transmission line properties, package design up to on-chip protection design with parasitic layout effects and ultimately the on-chip circuit(s) to be protected, being unpowered or powered. By using the full voltage/current versus time-domain response of an ESD protection device with the TLP test method [3-5], while knowing the excitation profile as generated by the TLP system, a high-order equivalent model can be extracted from the data. In this paper a proposal for a DoE multi-parameter statistical behavior model will be given together with the rationales [1, 2].

Dynamic Multi-Parameter Response Model for SEED Analysis

ABSTRACT: System Efficient ESD Design (SEED) [1] at present requires static response data from the devices and circuitry used along the protection chain, typically from the point of entry at the PCB boundary i.e. connector up to the circuit on-chip to be protected. On this path there may be external ESD protection i.e. voltage clamping, interconnect path delay with specific transmission line properties, package design, on-chip protection design all with parasitic layout effects and ultimately the on-chip circuit(s) to be protected, being unpowered or powered. The present way of using transmission line pulse (TLP) [2-4] to obtain the response parameters is inadequate as only the averaged I/V response parameters are used after 70% of the TLP pulse width used. With most commercially available TLP testers the bandwidth used (to obtain these I/V parameters at typ. 70 ns) is also insufficient to gather the full SEED information required. For the multiple SEED applications to be implemented, dynamic response parameters are needed in time and frequency domain, as the protection device response parameters are affected by the presence of RF energy e.g. with smart phone and other wireless appliances. Furthermore, the dynamic response parameters are a function of the DC bias voltage applied i.e. devices being powered or unpowered as well as temperature. In this 1 st paper constraints and ideas are given to gather the multi-dimensional response parameters together with their rationales. At the end of the paper some examples will be presented. Future parts will contain data analysis, model building and model validation.

Low-Frequency Magnetic-Field Immunity Surface Scan Method

ABSTRACT: Many sensor designs incorporating electronics are becoming more vulnerable to low frequency (LF) magnetic field (H-fields) when used in close proximity of electrically driven actuators, linear and rotating motors. The complex geometrical structure of the sensor’s front-end design is often unknown. The sensor’s front-end position is where the physical measurement quantity is transferred into an electrical quantity and then led up to the amplification stages. Again, given by the fact that low-frequency H-fields are hard to shield, the externally generated H-fields i.e. magnetic flux penetrates into the few sub-mm square area and induces interfering voltages: U = -d/dt = -dB.A/dt. At this moment, no formal H-field immunity requirements nor test methods exist which is applicable in the frequency range 10 Hz to 1 MHz. To be able to characterize the LF H-field immunity of these sensors, a surface scan method has been developed by which local H-fields can be injected in the various orthogonal orientations over the surface of the sensor by which its most sensitive orientation and response can be visualized. Knowing the absolute and orientation sensitivity of sensors can be useful in the selection process of sensors and will determine their fit-for-use prior to system integration.

Conducted mains test method in 2–150 kHz band

ABSTRACT: The frequency band from 2 to 150 kHz is used for most mains related power conversion applications, like uninterruptable power supplies (UPS), pulse width modulation (PWM) drives, active in-feed converters (AIC), switched mode power supplies (SMPS), solid state ballasts, LED drivers which are all polluting the domestic and industrial mains distribution networks. On the other hand, the same frequency band is used for power line communication (PLC) and distribution line carrier (DLC) communication systems as well as for most active capacitive, inductive and even resistive sensors. Most of these sensors have their carrier frequency within this band. As such, conducted emission as well as conducted immunity requirements need to be established for single phase, symmetrical and three phase applications and for grounding structures by using coupling and decoupling networks with a defined source/load impedance. The coupling and decoupling network shall be mains distribution network type independent: TN-S, TN-C, TT, IT. Disturbances within this band can occur either in unsymmetric, asymmetric or differential mode and may affect systems like power meters, residual current detection devices (RCD), active sensors and many other telemetry systems. Several International Standards (IS) have been published [3– 15] but none of them offers (yet) an unambiguous solution for the coupling and decoupling network(s) required. In this paper, a coupling and decoupling network is presented which can be used in this frequency range for measuring the RF emission from as well as enable the injection of disturbance onto a dedicated mains port. A network has been implemented for 3-phase power applications, is transparent at the mains frequencies: 50/60 Hz, and capable to handle up to 150 Amp/phase. Index Terms -coupling and decoupling network, single phase, symmetic and 3-phase mains distribution system, low frequency conducted emission, low frequency conducted immunity, power line impedance

Power grid, mains filtering and power line communications… a root cause for incompatibilities??

ABSTRACT: EMCMCC, the Netherlands The power grid is intentionally meant to distribute electrical energy at the mains frequency, as produced by the electricity generating plants, towards the end-users. The three-phase low-voltage distribution network can be utilized more efficiently when a power factor of 1 is achieved and no harmonic distortion is superimposed. Due to an increase of self-generated energy and the near to saturation increase of switching electronics, the loading of the mains distribution network is heavily affected. These same mains distribution networks are still considered for power line communication in two frequency bands: the lower one, 10 kHz -150 kHz (EN50065), and the one above from 1,6 MHz to 30 MHz e.g. HomePlug, IEEE1901. Power mains quality Power mains quality determines the 'fitness' of electrical mains distribution network to the end-user's devices. Synchronization of the voltage, frequency and phase allows electrical systems to function in their intended manner without significant loss of performance or life. The term power quality is used to describe electric power that drives an electric or electronic load and that enables the load to function properly. Without the proper power, an electrical device (or load) may malfunction, fail prematurely or may not operate at all. There are many ways in which electric power can be of poor quality and many more causes of such poor quality power. By the end-users, it is however generally believed that electrical power is provided 24/7 and capable to deliver the amount of electric power as expected. The electric power industry comprises electricity generation (AC power), electric power transmission and ultimately electricity distribution through an electricity meter located at the premises of the end-user. The electric power then moves through the mains distribution wiring installation of the end-user until it reaches a load. The complexity of the electric power system to transport electric energy from the point of production to the point of consumption is now combined with variations of the weather: PV (photo voltaic) and wind generation, demand and other factors provide many opportunities for the quality of supply to be compromised or at least be affected. While 'power quality' is a convenient term for many, it is the quality of the voltage -rather than power or electric current -that is actually described by the term. Power is simply the flow of energy and the current demanded by a load and that has become largely uncontrollable.

‘Live’ mains impedance measurement and analysis

ABSTRACT: Since the 1980-ties, the asymmetric mains impedances have been defined by IEC CISPR 16-1-2 [1] and used in an artificial mains network (AMN) suited in the frequency range (10) 150 kHz to 30 MHz. The mains impedance has recently been extended by the definition of asymmetric or common-mode artificial networks (AAN) and coupling/ decoupling networks (CDN) which are defined to be used in the frequency range 150 kHz to 80 MHz. All power mains impedances defined with these networks represent mean values from statistical data gathered and these networks are formally used to demonstrate conducted mains RF emission (and RF immunity) compliance in a defined and reproducible manner. However, other international EMC standards like IEC 61000-3-2 [4] and 61000-3-3 [5] consider mains frequency harmonic emission and flicker from the same mains wall outlet sockets with other impedances, this from the mains frequency upwards to 2 kHz. The mains impedance in the intermediate/overlapping frequency range from 2 kHz to 150 kHz is considerably less as defined by IEC 61000-4-19 [3] which is opposed to the mean values as given by IEC 61000-4-7 [2] where the mains impedances are much higher. In this paper, two 'live' mains impedance measurement techniques are given to obtain a detailed impedance behavior in time and/or frequency domain. Knowing the 'real' mains impedances means that one is able to forecast resonances and derive the optimal way on how to apply mains filters effectively, while using their appropriate parameters. Mains distribution optimization can also be used inside a large system or installation.

Assembled PCB EMC test methods

ABSTRACT: Most often, it is unclear where assembled PCBs are going to be used in and how these are being connected and applied. As such, it will be required, both for the OEM manufacturer as well as the end-user/system integrator, to know the EMC properties prior to system integration. EMC is, aside power integrity (PI) and signal integrity (SI), one of the crucial requirements to be met to ensure functional reliability of the end-product. The EMC requirements applicable need to be uncomplicated and easy to verify in a limited amount of test time. Last but not least, these EMC tests have to be applied in an environment which is close to the end-applications foreseen; rack-mounted, stand-alone, etc. The PCB test methods proposed cover the frequency range from (DC) several Hz to several GHz, both on RF emission and immunity. By exchanging the RF disturbance source by an impulse source, the test methods proposed can also be used with impulse immunity tests.

Time-domain surface scan method

ABSTRACT: The necessity of using dedicated EMI-receivers and compliant spectrum analyzers with CISPR detectors is based on an outdated approach. The levels that people perceive from AM/FM radio reception and analogue modulated television broadcast signals as interference is taken as reference. In the meanwhile new detectors: C_AV and C_RMS have been defined of which the software algorithm is patented which, as such, is delaying the acceptance of these new detectors to be included in IEC CISPR 16-1-1. For most of the EMC related issues, there is little need for such specific detectors as one has to recalculate the nuisance that the total disturbing signal provokes per system bandwidth anyhow. The effect that an RF disturbance might have on a broadcasted RF signal with limited bandwidth will be completely different from e.g. sensor applications where broadband demodulation might occurs. As such, EMC compliant products may still cause nuisance when other detection criteria apply. Time-domain based EMC measurement systems have been developed with just a single RF input [1]. However, for most of the surface and D scanning applications 3 or 4 RF inputs are needed e.g. for measuring the 3 orthogonal E/H-field components and the other input is used for synchronisation. For such applications, modern 4-channel digital oscilloscopes can be used which have add-on mathematical analysis capabilities for the signals obtained. By taking time-domain data with sufficient sampling resolution, the influence onto other susceptible systems can be post-calculated by applying the complex response characteristic of the system being interfered. However efficient data reduction is a prerequisite to limit data storage and enable post-processing.

Reducing compliance uncertainty with AMN measurements

ABSTRACT: In IEC CISPR 16-4-2 [1, 2] tight impedance requirements are given for artificial mains networks (AMN). Unfortunately, these tight requirements will support measurement uncertainty but still not guarantee low compliance uncertainty if the whole test set-up, up to the port of the equipment being tested, is not taken into account. In this paper the impact of the design of the AMN as well as the mains cable used is evaluated. Incorrect cascading of typical AMN elements: impedance stabilizing network, attenuator(s), high-pass filters and impulse limiter results in erroneous findings which affect measurement uncertainty. Introduction of impedance requirements on the mains cable used enhances the compliance uncertainty by 20 dB, which is demonstrated by simulations and measurements.

Extend your PI, SI and EMC Requirements to Enable Profound Modular Mechatronic Designs

Mechatronics means: mechanics combined with electronics. The amount of electronics involved in mechatronic systems is constantly increasing. The required precision, speed and stability of mechatronic systems is co-determined by the reliability of all kind of sensors with electronics, embedded controllers and pulse width modulated (PWM) motion drives with increasing performance and bandwidth.

Three-pole analysis model to predict SI and EMC effects

Accurate driver and package models are necessary to analyze the signal integrity (SI) and electromagnetic compatibility (EMC) issues on digital circuits. 2-pole models that assume an ideal power distribution system (PDS) are commonly used in modeling the SI of signal lines. This assumption makes real SI and EMC analysis worthless or at least only useful under certain restrictions. In order to account for all current return paths, the power and ground lines have to be considered as well. As such, the driver and the package is modeled as a 3-pole and a 6-pole network, respectively.

Resonant-free PDN design®

ABSTRACT: The design of power distribution networks (PDNs) on printed circuit board (PCB) structures, or even on interconnect structures inside IC packages, typically results, with or without decoupling capacitors added, in a network full of impedance resonances. These resonances functionally hamper fast digital and RF designs from several MHz up to the GHz-range onwards and are the root cause for many EMC issues. These resonances are caused both by the physical size and geometry of the PCB and the decoupling as well as the loading components added to that PCB. Utilizing the characteristic impedance of the adjacent supply and ground layers correctly, results in a resonant free supply PDN with an impedance which can be made very low over an extremely broad frequency range. This, in combination with ‘Kelvin contact’ decoupled ICs, assures that the low impedance of the PDN can be maintained and multiple decoupling capacitors are no longer needed near to the IC pins. This offers great advantages for PCB space allocation and opens opportunities to more efficient routing. This extended concept has been verified by simulations. Additional measurements were taken to validate the concept.

Automotive RF immunity test set-up analysis: Why test results can't compare …

ABSTRACT: Though the automotive RF emission and RF immunity requirements are highly justifiable, the application of those requirements in an non-intended manner leads to false conclusions and unnecessary redesigns for the electronics involved. When the test results become too dependent upon the test set-up itself, inter-laboratory comparison as well as the search for design solutions and possible correlation with other measurement methods looses ground. In this paper, the ISO bulk-current injection (BCI) and radiated immunity (RI) module-level tests are discussed together with possible relation to the DPI and TEM cell methods used at the IC level.

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