INA333: Signal coupling circuit for INA333AIDGKR

Hi Martin,

I'm going to need more information about your circuit to assist you with your question, such as:

• What are your power supply rails? 
• What is the maximum differential input voltage that will be applied to the INA333? What is the input common mode voltage?
• Could you provide more information about your application and your performance requirements?

Also, I recommend using the INA Vcm vs. Vout tool in the Analog Engineer's Calculator to verify that you will be using the INA333 in the linear operating range. With a single supply voltage of +5V, a common mode voltage of 2.5V, a gain of 100, and reference voltage of 1.65V, the differential input is limited to (-15.5mV, 32.5mV) for the INA333 to stay in the linear range.

Best Regards,

Alex Curtis

Hi Alex Curtis,

I was reviewing the design and had to make many modifications. I will open another thread where I will post the complete design, as I am planning to make a DIY differential probe for an oscilloscope and want to see how well it turns out.

Best Regards,

Martin.

Hi Martin, 

Please try our INA849, if you are interested to make a differential probe. It has input protection, larger BW, low noise and wider input range etc.. 

If you provide us a design requirements, we can provide you with a simulation. 

Here is an INA826EVM example --> you can follow the example, and layout INA849 as the DIY project. 

https://www.ti.com/lit/ug/sbou115c/sbou115c.pdf?ts=1717712521944&ref_url=https%253A%252F%252Fwww.ti.com%252Ftool%252FINA826EVM

If you have additional questions, please let me know. 

Best,

Raymond