I can probably shed some light into this subject as I am the original designer of the "Pelligrini" target.In 1978/1979 I designed the coaxial target for waveform verification as our client, Dave Reynolds of Digital Equipment Corp., insisted on certain waveform adherence from our company (Experimental Physics Corp.) The original target used a BNC connector and it was designed to have better frequency response than the one DEC was using consisting of two parallel PC boards with the resistors between them (nick-named the "ski-sled"). DEC was working with the IEC committee on 801-2 which got ahold of the target provided to DEC. Even Mr. Pelligrini does not know why it was named after him! The target design transfered to Electro-Metrics when Experimental Physics solds its ESD product line to Electro-Metrics which conitnued to market the target for a few more years. The basic design evolved into the "N" connector and SMA connector variants. University of Berlin along with Dr. David Pommerenke extended the design with surface mount resistors to beyong the original design's 1 GHz limit. The new generation targets perform above 4 Ghz with special versions operating at near 10 GHz. Many other target designs have been made such as the tapered line target by Jon Barth, the NiCr film target by the late Hugh Hyatt (my former partner at Experimental Physics), the Transmission line target by Hugh Calvin etc.
Hans Mellberg Engineering Manager BACL 230 Commercial Street Sunnyvale CA 94085 USA 408-732-9162 x38 408-732-9164 fax ----- Original Message ----- From: "Jim Ericson" <[email protected]> To: "emcpost" <[email protected]> Cc: "drcuthbert" <[email protected]> Sent: Saturday, May 03, 2003 4:09 PM Subject: Re: ESD Gun "verification" > > Dave: > > Yes. The current-sensing transducer that I built ("Pelligrini Target") is > per the Annex B drawings in EN 61000-4-2:1995 + A1:1998 +A2:2001. It has > five paralleled 240 Ohm resistors arranged radially around the oscilloscope > side to give 48 Ohms. On the ESD Gun side are twenty-five radially spaced > 50 Ohm resistors to give 2 Ohms. Transconductance is 1 Amp/1 Volt into 50 > Ohms. > > The present Standard requires a minimum 1 GHz bandwidth oscilloscope. > > I use a Pasternak Model PE7002-30 (DC to 2 GHz) 1 Watt Attenuator between > the Pelligrini Target and the scope (voltage ratio of 32). The oscilloscope > is a Tektronix 7104 with 7B10 time base, and a 7A26 dual-trace amplifier. > > I'll email a couple of photos to you (offline), and copy Mr. Pommerenke and > Mr. Kinney. > > Regards, > Jim Ericson > Acme Testing Company > [email protected] > > > ----- Original Message ----- > From: "drcuthbert" <[email protected]> > To: "'Jim Ericson'" <[email protected]> > Sent: Friday, May 02, 2003 8:07 AM > Subject: RE: ESD Gun "verification" > > > > Jim, > > > > I simulated this. I am assuming the circuit is a 2 ohm resistor to GND. If > so, the series inductance must be <0.1 nH for the 2 ohm resistor. Does this > sound right? I can do this with 25 paralleled 49.9 ohm resistors arranged > radially around the input (discharge) point. > > > > Dave Cuthbert > > Micron Technology > > > > -----Original Message----- > > From: Jim Ericson [mailto:[email protected]] > > Sent: Thursday, May 01, 2003 11:50 PM > > To: emcpost > > Subject: ESD Gun "verification" > > > > > > > > John: > > > > I faced the same problem about six years ago. I needed to do > "verification" > > in between the expensive annual "calibrations". I first explored the > option > > of buying a Pelligrini Target. As I recall, the quotes I received were > > around $2000. That seemed outrageous, so I decided to build one myself. > > I'll bet it took me at least 3 days to make sense of those goofy > mechanical > > drawings in 61000-4-2. If only they had included a photograph or good > > cross-section in the Standard! > > > > Anyway, I finally figured it out, translated the drawings into something > > understandable by a U.S. machine shop, and got all the brass parts > > fabricated locally. It took several in-process consulting sessions with > the > > machinist, but I finally got all the brass parts done for around $300. > > Then, I purchased a $25 silver electroplating kit. It was like Science > Fair > > time in my workshop! Some hours of painstaking soldering later, the > target > > was completed. I mounted it over a specially-drilled hole in the brass > wall > > panel of our anechoic chamber (you need a Faraday Cage of some sort, and > > this seemed the easiest). I did a quick check using our Tektronix 1 GHz > > analog oscilloscope ... and the risetimes and overall waveforms measured > > within spec! Then, I sent the target to Haefely-Trench for a > "calibration" > > (against their standard Pelligrini target). The results were very, very > > close. > > > > Having performed many verifications at this point, my advice (if you want > > fairly accurate and repeatable results): > > > > 1. Make (or buy) something resembling the 61000-4-2 target. > > 2. Use a Faraday Cage. > > 3. Be aware how important the POSITION of the ESD Gun Grounding Strap > is > > to these measurements ... especially to risetime measurements. I always > > take a photograph of the setup, including the "shape" of the Grounding > Strap > > and where it is attached. If you don't do this, you'll get pretty wild > > variability between verifications. > > 4. Even a 500 MHz oscilloscope would probably be OK for "verification". > > Just make certain that all setup parameters (including Ground Strap > > placement) are EXACTLY the same each time. That way, if the GUN happens > to > > change, you'll at least know what to do next. > > > > Give me a call if you'd like a photo. > > > > Good luck! > > > > Jim Ericson > > Quality System Manager/Sr. EMC Engineer > > Acme Testing Company > > Acme, WA. > > 888-226-3837 > > [email protected] > > > > ----- Original Message ----- > > From: "John Harrington" <[email protected]> > > To: <[email protected]> > > Sent: Thursday, May 01, 2003 11:45 AM > > Subject: ESD gun verification > > > > > > > > > > Hello All > > > > > > Does any one have a quick and dirty (and hopefully cheap) way to verify > > the > > > performance of an ESD gun. > > > > > > Please, no one suggest building the current sensing system described in > > the > > > back of IEC 61000-4-2. I don't understand the drawings let alone have > the > > > workshop or materials to consider it. Although, I may pay someone to > > build > > > it for me... > > > > > > I am desperate enough to consider buying something off the shelf (if I > > could > > > find said shelf). > > > > > > All help appreciated > > > > > > John Harrington > > > EMC Technical Manager > > > F-Squared Laboratories > > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: [email protected] > Dave Heald: [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > Jim Bacher: [email protected] > > Archive is being moved, we will announce when it is back on-line. > All emc-pstc postings are archived and searchable on the web at: > http://www.ieeecommunities.org/emc-pstc > This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
