On Tue, Apr 22, 2025 at 10:01 PM, nima wrote:
I am trying to build a model for MJ11021 to be used in an AB amplifier simulation.? Link to .
I made an attempt in building a model for the part PNP type first.? I also created a simulation to validate against the datasheet.
Validation part 1: DC simulation to Verify hFE and VCE.??
Never got past part 1!?
The main problem is this:? Your subcircuit pin-order is wrong.
?
The 'standard' SPICE pin-order for BJTs is C-B-E.? For .SUBCKT models you do not absolutely need to use that order, but it's a good idea if you do.? Your Darlington symbol uses that order.? But your .SUBCKT model definition has the wrong order, meaning that it does not agree with the Darlington symbol:
.SUBCKT MJ11021 B C E
Change that line, to this:
.SUBCKT MJ11021 C B E
and I think most of the problems go away; at least it gets you going in the right direction.
?
While you are editing the model file, also fix the last line:
.END
which must not be the .END command.? It should be this:
.ENDS
?
I also note that your .DC command has the wrong polarity for the increment value:
.dc V2 -1 -2.8 0.2
which should be:
.dc V2 -1 -2.8 -0.2
It might be better to use a current source instead of a voltage source, to drive the base pin.? But that's up to you.
?
Andy
?
