I can't find any spec listed, or any datasheet for the SOIC package. Is there a rating for what is the max voltage in a standard SOIC package from pin to pin? and other packages like DIP, and SIP which I presume would have the same rating as DIP right?
The best I can find is ratings for DIP switches:
https://www.mouser.com/datasheet/2/670/ds04_254_smt-1777718.pdfWhich it seems like they rate it at 500VAC form pin to pin.
It will also depend on the PCB footprint, which is often wider than the pins themselves.
High voltage parts in such packages (such as SMPS PWM controllers with built-in MOSFETs) typically use one pin in the corner for high voltage and then completely remove the pin next to it.
Depends on packaging material, and project regulations.
IR21xx for example are available in SOIC-8 and claim 600V handling. Have also seen TSSOP/MSOP hot swap / load controllers rated say 100V.
IC packaging resin may be considered to have a better than usual CTI (comparative tracking index); it's surprisingly rich in silica. Perhaps if arcing occurs, the organic binder burns away as much as it carbonizes?
If it matters, you'd likely want to either:
a) ask the manufacturer about the part ratings, standards met, and packaging material;
ask the certification agency (i.e. UL, etc.) what they think about it;
go back and forth until a suitable device has been selected; or,
b) just get the SOIC-14 part with gaps (NC pins) included. Or parts with the pins removed (more common in offline SMPS controllers, I would say?).
Tim
Which it seems like they rate it at 500VAC form pin to pin.
I don't think they can claim 500VAC in between pins since this is an SMD component which should be mounted on a PCB so that voltage is dependant on substrate, humidity, etc. I've seen tracking occur at lower voltages in larger distances...
Offline AC/DC converters have up to 800V mosfets in SOICs, but never pin-to-pin, *and* the board is usually routed with cutouts...
Simple, as stated by the device datasheet, if it says a pin supports 800V right next to a gnd pin, it does!
Normally such devices come with layout recommendations.
Plasma TVs Y-boards have 0.5mm pitch TQFPs drivers, IIRC handling 100-200V (These supplies are called VA, VS), generating high frequency ac signals, of course any dirt or moisture would cause arcing, but they're dipped in silicone.
Still, strange to see that bunch of tight traces happy with it.
