Hi, I have never worked with a lab that has discharged to exposed pins of a connector. I think the basic rationale is that when one approaches a connector with a charged finger, the discharge is most likely to arc to the surface with the most inherent capacitance, which would be the D-shell or grounding ring of the connector, the part connected to the return reference or chassis refernece of the circuit. Discharging to pins under normal circumstances is much less likely.
Without knowing more of the detail of this product's construction, it is difficult to determine if the lab is being overly enthusiastic or if it has determined that this particular construction is so far out of the norm that it is highly likely that, under normal use, the pins are the likely discharge point from a charged person or object. Regards, [email protected] ---------- From: Steve Chin To: emc-pstc Subject: Re: ESD testing on exposed c List-Post: [email protected] Date: Tuesday, April 16, 1996 9:44AM Moshe asked about ESD testing directly on the pins of a bare connector. The lab I test with has told me that they do not discharge directly to = the exposed pins of a connector to which no cable is connected. They = quoted many reasons, including the ECMA spec Moshe quoted, as well as the = fact that we usually do the radiated emissions tests with a fully = populated system and the ESD and other immunity tests with a pretty bare = system (which creates the assumption that the end-users will configure = their systems similarly to the radiated emmissions test system, therefore = making the possibility of an end-user discharge to the pins extremely = remote). They said that your argument against discharging directly to the pins = could include the fact that your expected user configuration would = include cables populating those connectors (assuming the vacant = connectors are for peripheral support equipment, not vital connections = for operations). Ah, I ramble on (and I'm probably not intelligible). Steve Chin FWB, Inc. Menlo Park, CA, USA [email protected]
