This thread has been locked.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.
Part Number: INA597
i am looking to the layout attached. its a differential amplifier based on 2 op amp and a variable resistor to balance a DUT. Could you please advice a circuit and opamp that could do the function up to 2-3 MHz..
Thank you for your post. The INA597 is a difference amplifier with high value input resistances. If you are trying to measure large currents, like in the ampere range, then a difference amplifier or an instrumentation amplifier will be okay.
However, if the measured current is very small, like in the uA or mA range, you will need to take a look at an instrumentation amplifier.
The INA821 may be a good option for you as it is a high precision instrumentation amplifier with 4.7MHz of bandwidth: http://www.ti.com/lit/ds/symlink/ina821.pdf
-Tamara Alani Learn more about IAs here.
We are glad that we were able to resolve this issue, and will now proceed to close this thread.
If you have further questions related to this thread, you may click "Ask a related question" below. The newly created question will be automatically linked to this question.
In reply to Tamara M Alani:
thank you for your feedback, i tried to simulate waveform using TINA at high frequency 2MHz but i am getting strange output. my purpose is to balance R2 via R1 to get vout 1 =Vout2 for frequency omega (here 1000 Hz and 2 MHz). I also get an unusual peak at the onset. R2 will be devices with resistance in the range 20 - 90 ohms so i need to have R1 as a potentiometer to balance and cancel out the output. i added some capacitors at the power supply but it doesnt improve the waveform. any suggestions welcome.i attached some files if can help.
In reply to Ahmed Ahmed38:
Thanks for your reply.
1325.diff amp from Ahmed.TSC
Dear Tamara ,
thanks for your feedback. for vin typcally can be a volt or less i used 500mV but the frequency is omega, this is the harmonic i want to cancel out owing to the differential opAmp circuit. i am only interestd in the 3rd harmonic originating from the DUT R1. I simulated using a steady state solver for 1ms. the R1 is a device that shows variability between most likely 20 to 90 ohms. to balance that signal so that the resulting vout=0 i balance with a potentiometer as R2 ( here i just used fixed values) but when i run the simulations i get a transient not sure if it is related to the op Amp or solver. also could you advice on the capacitors are they necessary?
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.