Can anyone tell me the correct 'connection wiring' for incorporating an LSK389B dual jfet in an LTspice circuit?
When I select that component from the list ... it comes out as this:
But the LSK389 has 6 legs - see here:
Does LTspice simply assume that:
* legs 1 & 4 are joined
* legs 2 & 5 are joined, and
* legs 3 & 6 are joined
- and so just displays the standard 3 connections (Drain, Gate & Source)?
Thanks
When I select that component from the list ... it comes out as this:
But the LSK389 has 6 legs - see here:
Does LTspice simply assume that:
* legs 1 & 4 are joined
* legs 2 & 5 are joined, and
* legs 3 & 6 are joined
- and so just displays the standard 3 connections (Drain, Gate & Source)?
Thanks
LTspice is not for pcb design so the symbols do not need to map to the physical or a footprint. No PIN numbers are required.
So all you need to do is instantiate two of them since they use the same model thus are inherently matched. You can label them as J5A, J5B and LTspice won’t care.
So all you need to do is instantiate two of them since they use the same model thus are inherently matched. You can label them as J5A, J5B and LTspice won’t care.
Sure, LTspice is not used for PCB design - but you do need to connect all the components correctly ... otherwise the circuit you are designing in LTspice won't work as intended. 😳
For instance - if you actually use a pair of jfets in a real-world circuit (to get twice the gain) ... if you just use one in the LTspice simulation ... you won't see the correct gain.
Sorry, I'm afraid I'm not 100% certain what you are saying ("instantiate"??).
Am I correct in assuming what you mean is ... just use two of the LTspice artefacts:
... in the LTspice circuit - marked 'J5A' and 'J5B' - to represent a single LSK389B - J5 - on the PCB? And on the PCB, make sure the appropriate pairs of pins on the LSK389B are connected?
If so, then if I was modelling a circuit which currently uses a quad of 2SK170s (no longer available - so I have to use LSK389Bs), would I simply:
1. use four of these in the LTspice circuit:
but
2. only install two LSK389Bs on the circuit board?
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One LT spice symbol is simply half of the actual part. LT spice just just treats it as a single jfet
That’s correct you instantiate or place two symbols (artefacts) in LTspice representing one physical lsk389 device.