Hi,
I am using the INA849 IC. My goal is to use 8V power rails, with a mid supply (4V) reference input to the in-amp. While simulating the circuit, my output waveform gets clipped.

Please guide me. Is there a particular connection I am not doing correctly?

 

Hi fbp,
What value of Rg resistor do have in circuit??

E

 

I am using the in-amp as a unity gain amplifier for now.

 

Do we have the give an offset of 4V to the input for the in-amp?

 

hi,
Check the datasheet for the resistor value you need for your required Gain.
E

 

Do we have the give an offset of 4V to the input of the in-amp or directly give the input without an offset?

 

I want to have it as a unit gain amplifier, and I am using an in-amp sicke it has good CMRR. While simulating the circuit, do I have to put a resistor of 1 ohm?

hi,
Check the datasheet for the resistor value you need for your required Gain.
E
View attachment 300958

 

hi,
If you want the Vout to be centred around +4v, use a Vref voltage,
E

 

Yes I did give 4V as the reference input to the INA849 through the LT6231 opamp.

 

Hi,
Look at that table for gain of unity, the Gain figure is not available.
What is the Input signal?
E

 

Hi,
You could use a 2:1 resistive voltage divider on the Input and set the Gain for 2, 6.04k resistor.
E

 

Hi,
Like this option.
E

 

The input signal is a 5Vpp signal with 500kHz. I am just not sure if a 4V offset is required at my input as well.

I am not able to access the link you shared in the previous message

 

Sorry, I was able to view the image, it took time to load. I was wondering why a voltage divide at the input?

 

You need to treat the mid voltage as your signal ground.

Connect the sine generator ground and the + input to the mid point voltage, not to the the battery negative.

 

Is it to compensate for the gain of 2?

 

You need to treat the mid voltage as your signal ground.

Connect the sine generator ground and the + input to the mid point voltage, not to the the battery negative.

I have to set the input as mid supply as well?

 

I have to set the input as mid supply as well?

Yes, it is the signal ground. If you connect an input to the battery negative, it is at -4V with respect to the reference voltage.

Think of the voltages this way: The midpoint is 0V, the supply positive is +4V and the supply negative is -4V.

 

Yes, it is the signal ground. If you connect an input to the battery negative, it is at -4V with respect to the reference voltage.

Think of the voltages this way: The midpoint is 0V, the supply positive is +4V and the supply negative is -4V.

My input was actually already set to mid-supply. Am I doing something wrong in the connections or n the schematic?

 

hi fbp,
This is what I see with your circuit.
What do you want the Vout to be ???

E