INA199: output capability

Ann_Lien

Part Number: INA199

Hello expert,

My customer would like to know how to judge INA199A3 output capability. Since they use INA199A3 output as source and it's divided by voltage divider with 200 ohm and 1ohm, output voltage is not correct. I think output impedance is too small but I'm not sure how to explain to them. Searched from datasheet and I found figure 6 describes output swing vs. output current. I'm not sure if it is okay to explain to them with figure 6, or we have better way to explain this issue? Thanks a lot!

Best regards,

Ann Lien

over 4 years ago

0 kai klaas69 over 4 years ago

Guru 140200 points

Hi Ann Lien,

figure 6 of datasheet of INA199 is perfect for explaining :-)

Kai

0 Javier Contreras4 over 4 years ago in reply to kai klaas69

TI__Mastermind 29460 points

Hello Ann,

Maybe if they don't understand figure 6 you could show a simulation like I have attached. From my example the Vout of INA199 is expected to be 4V. I then swept the load at the output. From the diagram Vout(INA199) vs R2 shows that the output cannot reach the 4V and gets much less as you decrease the resistance which would require much more current. I have attached the TINA simulation file as well.

INA199_OutputDrive_limitations.TSC

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INA199: output capability