Thanks for the free lesson. In a USB 2.0 application I had an issue with the TVS diode capacitance. By soldering a TVS diode (SP0502BAJTG) with roughly 40pF capacitance the PC was not able to recognize the device. Changing the diode with a 0.4pF capacitance TVS diode (szesd7205dt5g), the device works fine
Great video Robert and Andreas! One minor confusion (really feedback to Andreas): at 33:48 the performance of the upper schematic in the grey box (large schematics on the left) is plotted in blue in the lower trace, while the the schematic in the lower blue box is plotted in upper grey trace. It would make the point much clearer and quicker if the two schematics swapped colors and positions.
Very insightful content. Till now i only had the protection aspect of these devices in mind. This video made me realise the effects of these diodes on communication lines.
Great Video! One thing that is still confusing for me is the selection of these components based on their parameters. e.g; what should be the trigger voltage, breakdown voltage, clamping voltage for a 3.3v signal lines of an IC where it mentions absolute maximum rating of 3.6 volts in the datasheet? Should we select an ESD protection diode with clamping voltage less than 3.6 volts, if yes, what should be the trigger voltage? It would be Great if you explain these parameters with an example in a separate video. Thanks ♥
Phils Lab is explaining this very good. Also look at Application Notes from different manufacturers about ESD Protection. Those voltages are being explained there properly
One thing i was missing in the segments about direct, indirect and air discharge is the test with a coupling plate. You have a metal plate (roughly 50x50cm) that is connected to earth over a 1MOhm resistor. You place that plate in 10cm distance to your device (EUT) (you move the plate or the EUT around to cover every side individually). Then you apply the ESD pulse with the ESD-gun directly connected to that plate. The idea here is that you create a very fast and pretty broadband electromagnetic field impulse with discharging into the plate, and if your design has any bad antenna structures, they could pick up that impulse and potentially trigger a system reset, disturb communications or register a false user input. This is part of the EN 61000-4-2 standard
The test you describe seems more like EMI (ElectroMagnetic Interference) rather that ESD (ElectroStatic Discharge), which is the subject of the video. EMI is, of course, important, but a topic in its own right, I think, and leads to PCB design strategies rather than selection of ESD components, I think.
I've spent weeks working with a fluorescent CFL round (circular ring) light directly above my circuit board, about 6 inches away from the circuit board. I've had at least 5 Mosfets and also small TO-92 transistors that mysteriously stopped working or never worked. I've never in my life experienced failures like this. I put my Oscilloscope near the light and it produces 50Khz, a sine wave that emits 6 inches away from the bulb, in the open air, without the test leads touching the fixture. I tried searching online to see if a CFL can cause static electricity or a simulated ESD failure. I can only assume that it does. The light is effectively a charged high voltage plasma, emitting a strong electrical field around it. Are fluorescent lights safe to have near transistors and Mosfets?
1:01:34 and following, Andreas repeatedly refers to some term I couldn't catch -- "something parameters", where "something" appears in the auto-captions variously as "skater" "scaling" "catering".
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Thanks for the free lesson. In a USB 2.0 application I had an issue with the TVS diode capacitance. By soldering a TVS diode (SP0502BAJTG) with roughly 40pF capacitance the PC was not able to recognize the device. Changing the diode with a 0.4pF capacitance TVS diode (szesd7205dt5g), the device works fine
I always find this subject fascinating. Thank you to Andreas and Robert !
thanks, Robert very useful topic, especially (External vs internal ESD protection 1:07:18)
Great video Robert and Andreas! One minor confusion (really feedback to Andreas): at 33:48 the performance of the upper schematic in the grey box (large schematics on the left) is plotted in blue in the lower trace, while the the schematic in the lower blue box is plotted in upper grey trace. It would make the point much clearer and quicker if the two schematics swapped colors and positions.
Very insightful content. Till now i only had the protection aspect of these devices in mind. This video made me realise the effects of these diodes on communication lines.
Great Video!
One thing that is still confusing for me is the selection of these components based on their parameters. e.g; what should be the trigger voltage, breakdown voltage, clamping voltage for a 3.3v signal lines of an IC where it mentions absolute maximum rating of 3.6 volts in the datasheet? Should we select an ESD protection diode with clamping voltage less than 3.6 volts, if yes, what should be the trigger voltage? It would be Great if you explain these parameters with an example in a separate video.
Thanks ♥
Phils Lab is explaining this very good. Also look at Application Notes from different manufacturers about ESD Protection. Those voltages are being explained there properly
One thing i was missing in the segments about direct, indirect and air discharge is the test with a coupling plate. You have a metal plate (roughly 50x50cm) that is connected to earth over a 1MOhm resistor. You place that plate in 10cm distance to your device (EUT) (you move the plate or the EUT around to cover every side individually). Then you apply the ESD pulse with the ESD-gun directly connected to that plate.
The idea here is that you create a very fast and pretty broadband electromagnetic field impulse with discharging into the plate, and if your design has any bad antenna structures, they could pick up that impulse and potentially trigger a system reset, disturb communications or register a false user input. This is part of the EN 61000-4-2 standard
The test you describe seems more like EMI (ElectroMagnetic Interference) rather that ESD (ElectroStatic Discharge), which is the subject of the video. EMI is, of course, important, but a topic in its own right, I think, and leads to PCB design strategies rather than selection of ESD components, I think.
Wow, great content once again. keep on doing more videos
I've spent weeks working with a fluorescent CFL round (circular ring) light directly above my circuit board, about 6 inches away from the circuit board. I've had at least 5 Mosfets and also small TO-92 transistors that mysteriously stopped working or never worked. I've never in my life experienced failures like this. I put my Oscilloscope near the light and it produces 50Khz, a sine wave that emits 6 inches away from the bulb, in the open air, without the test leads touching the fixture. I tried searching online to see if a CFL can cause static electricity or a simulated ESD failure. I can only assume that it does. The light is effectively a charged high voltage plasma, emitting a strong electrical field around it. Are fluorescent lights safe to have near transistors and Mosfets?
1:01:34 and following, Andreas repeatedly refers to some term I couldn't catch -- "something parameters", where "something" appears in the auto-captions variously as "skater" "scaling" "catering".
Hmmm, maybe the term is "scattering parameters"? ("A" should be pronounced like in "cat", not as in "cake".)
ESD Compoents should be connect to Chassie GND, or IC GND?
I’m always confused about dealing with ESD and TVS diodes in Isolated IO sections myself.
Ja? - Ja!
I disagree that contact discharge is executed with power off