INA138 to INA139 LTSpice Simulation Adjustment

[ACharnley]

There's a TI model for the INA138 which works well and a much more complex TI model for the INA139 which doesn't work at all. I need the latter for the higher bandwidth and being a simple current sense chip have been looking to modify the values.

INA139 has 1K resistors on the input and INA138 has 5K.

Is it simply a case of modifying R11 and R20 in the attached lib? I ask because there's also another value at 5K, R20, and my best guess is it's to limit the max current going through the 1N1673.

 

[eTech]

The TI model works.

 

[tepalia02]

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[ACharnley]

*ignore*

 

[ACharnley]

Ah this is the Tina version, I'd gone with the PSpice file thinking it would be 'more compatible'.

 

[ACharnley]

First, thanks for making the asc file, I still haven't working that side of ltspice out.

So I dumped it into a project but the simulation gets stuck. My hacked INA138 to INA139 file is working, though slow as hell. My CPU is certainly burning watts on it.

 

[eTech]

First, thanks for making the asc file, I still haven't working that side of ltspice out.

So I dumped it into a project but the simulation gets stuck. My hacked INA138 to INA139 file is working, though slow as hell. My CPU is certainly burning watts on it.

At 166kz it will be slow no matter what. But the TI model design doesn't help either.

 

[eTech]

First, thanks for making the asc file, I still haven't working that side of ltspice out.

So I dumped it into a project but the simulation gets stuck. My hacked INA138 to INA139 file is working, though slow as hell. My CPU is certainly burning watts on it.

I made a small change to the lib file. Try this.
It sims much faster but still slows down at 60ms. I think that's caused by the circuit design.