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#1 Nov 11, 2020
waulu13
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Last seen: 3 years 4 months ago
Joined: 2020-10-16 06:20

OPA340 Open Loop Gain

Hello,

 

I am following this video,

 

https://training.ti.com/ti-precision-labs-adcs-selecting-and-verifying-d...

 

and I would like to plot the open loop gain as Texas did. Texas TI uses the Tina TI simulator but I would like to use the PSpice TI. The first time I tried to simulate it complained about the source V4 suggesting that I needed to add a resistor, R4. After that, the AC Sweep analysis takes a lot of time and fails to complete the simulation.

Project link,

https://1drv.ms/u/s!AhBVOtfpdktyoDXNWkD06Hic0Nwd?e=JIu4wd

 

 

Best regards,

 

EDIT: Is it possible to read directly (or through some math calculations) the Open Loop Output Impedance from the PSpice model of OPA340?

Thu, 2020-11-12 18:16
retiredEE
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Last seen: 1 year 3 months ago
Joined: 2018-03-21 12:19

I set up a simple single ended voltage follower using the OPA340.  I then ran a bias point analysis and experienced the same long analysis time as you did so I cancelled out early.  I added a negative voltage source to VEE and ran the bias point again.  This time it completed the calculations in a very reasonable amount of time.  Something isn't right with that model.

Fri, 2020-11-13 04:06
waulu13
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Last seen: 3 years 4 months ago
Joined: 2020-10-16 06:20

Thank you retiredEE,

 

I will just contact Texas Instruments to try to solve the problem.

 

Best regards,

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