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PMICnewbie , 01-27-2024, 07:54 AM

Is it allowed to change Vendor symbols or will it mess up with creating netlist or referencing part footprints or DRC. In my own Project for a switching converter where I have to use both an NMOS and a PMOS, the NMOS is 4 terminal while the PMOS is 6 terminal.

1. Was it ok to edit the symbol from before to after to resemble similar shape as the complementary NMOS? I mainly used the same internal drawing structure but was careful with the PIN properties, I did also cross reference and update the "U" attribute. and the PCB footprint and manufacture part number and the other package+part properties

2. For the Pin Properties, While copying the PMOS pins to a modified NMOS-->PMOS symbol it did not visually show the basic attributed (in blue) which is the pin name, but clicking the "pin name visible" property did show the value. Is it ok to leave it invisible as it clutters small symbols with bigger fonts? What is the shortcut of adding a basic attribute (HELP documentation said "File – Load Attributes" but couldnt locate it)

PS: according to the pspice codes its supposed to be three terminal pins for both NMOS and PMOS with 'D' 'G' 'S', I believe so that would indicate that the same signal goes to multiple pins on these switches

QDrives , 01-27-2024, 08:28 PM

Q: Is it allowed to change Vendor symbols
A: Yes

Q: Was it ok to edit the symbol from before to after to resemble similar shape as the complementary NMOS?
A: Yes. However, the symbol needs improvements. The N-Channel is much better. https://www.watelectrical.com/wp-content/uploads/Power-MOSFET-Symbols.jpg

Q: I did also cross reference and update the "U" attribute
A: The designator of a MOSFET is either Q or T.

Q: it did not visually show the basic attributed (in blue) which is the pin name
A: It is better to show a "G", "D" and "S" (once) than the pin numbers.

Q: What is the shortcut of adding a basic attribute
A: I do not know as I don't know OrCad (assuming the tag is correct).

Q: I believe so that would indicate that the same signal goes to multiple pins on these switches
A: Yes, MOSFETS often have multiple pins with the same function. Either a single pin cannot handle all the current or using a standard package, just connecting multiple pins to use them all.