I'd ask your customer. The 50% may relate to specific materials characteristics of the insulating medium.
flash•o•ver (flashover)
n.
1. An unintended electric arc, as between two pieces of apparatus.
2. The temperature point at which the heat in an area or region is high enough to ignite all flammable material simultaneously.
FLASHOVER: A disruptive discharge of electricity through an insulator, normally characterized by a voltage drop. Also, a discharge around or over a liquid or solid material. This can be a single event, intermittent or continuous. Same as Arc.
our customer can not explain what it means too because he fears to communicate with his mother company in japan so we are stuck here for few months. As we am requested to finish the ESD test within 5 days - deadline. I would appreciate if any one could help me out here. Attached is the test method.
A web search turned up this document on HV testing http://192.248.9.65/HV_Chap9.pdf . It mentions 50% flash-over a couple times, such as:
"(i) 50 percent dry impulse flash-over test, using an impulse generator delivering a positive 1/50 u
s impulse wave.
The voltage shall be increased to the 50 percent impulse flash-over voltage (the voltage at which approximately half of the impulses applied cause flash-over of the insulator)"
I'm no expert in such tests, but his looks like an encouraging article to start looking for info.
Tim F
__________________ To wonder is to begin to understand.
From the looks of things I feel I can add a bit to the information here. In one of my past jobs, high voltage discharge testing was my main duties.
The 50% discharge does indeed mean set the voltage to a point where the shot you apply causes a "flashover" about half the times you apply it. It looks like your file describes the type of circuit loading the test generator needs. (the 150 pF is the capacitance and the other call out is the resistance) I can't tell for sure but usually the resistance is put in series with the voltage source on one end and the capacitor on the other end. Then the other end of the capacitor in attached to ground.The DUT is put in parallel with the capacitor.
This type of test is usually done to check the integrity of insulation, and can really generate even higher voltages when the dischage occirs. Safety should also be a concern for this test.
Hope this helps a little.
Lary
__________________
I want to use a little known technique known as "The right way!"
One more question !!!
If I trying to withstand 25 kV impulse into DUT (device under test), 2 second per period, 10 times, non-dischage, with load by 12V, have any concern need to take care about the PCB layout ? How about the copper strip width and distance ? can add a surge protector (such as Epcos T230-350X) between the circuit or not ?
ESD test 50% flashover discharge - Do anyone know that 50% flashover discharge means?
ESD test 50% flashover discharge
Linear Mode
