Radiated Susceptibility Investigation of Electronic Board from Near Field Scan Method

Transcription

1 Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd Niclas LACRAMPE Wrk supprted by EFT SAFE3A research prject (Prject reference : ANR-14-CE ) July, 6th 2017

2 Outline 1 Mtivatin and intrductin 2 Near Field Scan immunity (NFSi) methd Perspectives and cnclusin Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 2

3 Immunity management f electrnic bard : hard challenge t maintain cmpetitiveness f prduct Nrmalized measurement methd nt adequate fr failure diagnstics. (GTEM, anechic chamber, reverberant chamber) Find investigatin methd t identify the rtcause f nn cmpliance t immunity requirement. Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 3

4 Mtivatin Near field scan methd well-knwn fr measuring electrnic bard and IC radiated emissin. Reverse this methd t inject lcal radiated disturbances t prduce cartgraphies f aggressin sensitivity. Methd prpsed as an extensin t the nrmalized measurement methd t prvide feedback t the IC r PCB designer. Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 4

5 Near Field Scan immunity methd : Principle Methdlgy fr CW injectin n DUT IEEE bus PC Mnitring Scan table 3D Displacement System RF signal generatr Autmated Near Field scan test bench at NEXIO DUT status Near Field injectin Pwer amplifier Pwer meter DUT Directinal cupler Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 5

6 Near Field Scan immunity methd : Calibratin Calibratin phase : useful t quantify the measured susceptibility. Calibratin Methd : recrd excitatin amplitude (net pwer, synthesizer input value) t induce a given vltage n a reference device Used a 4cm rund wire ver a grund plane (50Ω adapted up t 2 GHz) Wire terminated by 50Ω SMA lad and input f spectrum analyzer NFSi prbe placed at 1mm abve the line. Characteristic impedance f wire Injectin test bench 34.5 dbω 33.5 dbω 1MHz 2 GHz Spectrum analyzer Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 6

7 Near field prbe characteristics based n small lps fr magnetic field prbe. Cnstructin : small lp prbe built at the end f a semi-rigid caxial cable RG405. Varius iteratins t find gd cmprmise : imprve the prbe efficiency : diameter f the lp number f turns Nt degraded reslutin Alternative chse : Place magnetic cre inside the cil t increase the magnetic field in the vicinity. NFSi_D58t V2 Φ wire: 0.3mm NFSi_D58t V1 Φ wire: 0.3mm Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 7

8 Near field prbe mdeling (1) Simulatin realized n CST studi suite. Study in cllabratin with AIRBUS All parts f prbes includes except SMA cnnectrs. (caxial cables, wires and ferrite). Interest f simulatins : Design varius prbes, fit impedance & ptimize prbe size Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 8

9 Near field prbe mdeling (2) Cupling mdel between magnetic prbe and micr-strip line. Simulatin realized n FEKO EM sftware. Study in cllabratin with LAAS-CNRS. Multi-turn near-field prbe Excitatin f the prbe with a cnstant pwer. Line under test Extractin f the induced vltage at ne 50Ω terminatins f the line under test. Perfect grund plane 50 Ω terminatins Increasing f injectin level with ferrite (nearly 10 db up t several MHz) Abve 100MHz, n advantages t add ferrite. Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 9

10 NFSi test setup Injectin test bench EUT and NFS EUT Pwer supply Mnitring Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 10

11 EUT descriptin Output 0 3V 100 KHz Duty cycle : 50% ARINC cmpnent receiver Differential signal +10V 0V -10V ARINC cmpnent Driver Input 0 3V 100 KHz Duty cycle : 50% ARINC Receiver ARINC Driver Mnitring VHH VHL 5µs Pass / Fail criteria mask 1µs 4,3V 3,3V 2,8V 1µs 0,5V 5µs 0V -1V Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 11

12 NFSi results (1) VOUT_H VOUT_L Input Diff. signals VDDN Output Errr n ARINC utput signal Default : Mdulatin Frequency : 200MHz - Hy Frequency : 100MHz - Hx Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 12

13 NFSi results (2) Input Diff. signals Output Errr n ARINC utput signal Default : ffset n signal Errr n ARINC utput signal and differential signal Default : N signal Frequency : 500MHz - Hy Frequency : 800MHz - Hy Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 13

14 NFSi interpretatin Near field scan methd in immunity mde : Pssible t lcate the sensitive area. Identify area in default fllwing the frequency f Lw frequency t 300MHz: susceptibility n differential utput and VDD cnnectin. (mdulatin 500MHz: susceptibility n differential utput pins. (jitter 800MHz : susceptibility abve ARINC chip. (cmpnent stpped ) Difficult t realize same analyze with ther radiated immunity methds using TEM cell, anechic r reverberant chamber... Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 14

15 50 hms (100W) TEM test setup ARINC receiver ARINC driver TEM cell Fischer (FCC-TEM-JM1) Input pwer (500W max) Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 15

16 TEM result Field strength calculatin : P : net pwer (W) E: Field strength (V/m) d : Separatin flr-septum (m) Z: TEM characteristic impedance (Ω) With 85W injected in FCC-TEM-JM1, Field strength given by calculatin is : 1500V/m Test perfrmed with (and withut) cpper tape arund the ARINC cmpnent. N disturbance n utput signal : Light mdulatin appears n utput signal. Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 16

17 Calibratin cefficient (db V/W) TEM cell vs NFSi calibratin Cmparisn between NFSi and TEM cell calibratin test Used a 7mm rund wire ver a grund plane (50Ω adapted) Wire terminated by 50Ω SMA lad and input f spectrum analyzer NFSi prbe placed at 1mm abve the line. Same excitatin fr bth methd : cnstant pwer n [1MHz-1GHz] Need mre pwer with TEM methd than t inject similar vltage induced n the wire. (arund 30dB) Nise flr Frequency (MHz) with NFSi_8t-V1 prbe with NFSi_8t-V2 prbe TEM methd Nise flr Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 17

18 and perspectives Advantage f : Lcalizatin f susceptible area n design n specific electrical bard. Difficulty: Test time (test every frequency at every test pint). Impedance matching between injectin prbe and amplifier. Wrks in prgress : Reduce test time (Dwell time, pulse injectin ) Develp new algrithm t perfrm a rapid measurement Adapt NEXIO cmmercial sftware t realize NFSi test. Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd 17/07/06 18

19 Radiated Susceptibility Investigatin f Electrnic Bard frm Near Field Scan Methd Niclas LACRAMPE Wrk supprted by EFT SAFE3A research prject (Prject reference : ANR-14-CE ) QUESTIONS??? July, 6th 2017