TLV9062: Any Reference Design Available for TLV9062 in Amplifier & Comparator Applications?

Hello Sampath, welcome to the TI e2e forums.

1) Designing Gain and Offset in Thirty Seconds

2) I am not aware of any specific concerns other than Vos may grow a little bit wider.

3) High temperature and large input difference cause some Vos shift. Hysteresis gives more noise immunity.   

Thank you for your response... I'll reach out if I have any further questions.

Hi,

As mentioned previously, I am using the TLV9062 for signal amplification and comparison in my design, with a 3V supply. My comparator reference voltage is set to 2.5V, and I am getting the expected output. However, I have some concerns regarding the comparator output and alternative op-amps.

• The comparator output is +3V to -3V in simulation.
• Will this output be suitable for direct interfacing with a microcontroller GPIO?
• Is this design sufficient for hardware prototyping?

Alternative Op-Amps:

• Other than the TLV9062, will LM358 or LM2904B perform the same function in my design?
• Are there any key differences or limitations when using LM358 or LM2904B instead of TLV9062?

Design Optimization:

• Based on my setup, are there any modifications you would recommend to optimize performance and reliability?

Looking forward to your expert guidance.

Sampath,

Sampath Kumar said:

Will this output be suitable for direct interfacing with a microcontroller GPIO?

No, it is not good.

Sampath Kumar said:

Is this design sufficient for hardware prototyping?

The design is not ready yet. Supply is 6V, that is a little too high for TLV9062. What is microcontroller voltage? Do you have access to both  ZCT leads, in other words, do one side have to be grounded?  

I see two outputs, VF2 linear and VF1 non linear. Do you plan to use both outputs or just the final digital output? 

In any case give me the math equation(s) for output(s).

1.Supply is 6V, that is a little too high for TLV9062 & What is microcontroller voltage?

I am using a 3V supply for the TLV9062 in my design. However, in the simulation, I assigned separate power supplies for each op-amp. I made a mistake by setting the comparator stage supply to 5V instead of 3V, whereas in the actual hardware, both op-amps will operate from the same 3V supply.

Microcontroller voltage is 3.25V.

2.Do you have access to both  ZCT leads, in other words, do one side have to be grounded?  

I am using the MR-1 ZCT. Yes, I have access to both ZCT leads, and the ZCT is grounded in my design.

3.I see two outputs, VF2 linear and VF1 non linear. Do you plan to use both outputs or just the final digital output?

I am using only the final digital output to the MCU, and for verification purposes, I have checked the amplified output in simulation.

[Is there a method to obtain a comparator output of 3V to 0V instead?]

4.In any case give me the math equation(s) for output(s)

Amplified Output (VF2):

VF2 = (1 + Rf / Rin) * VZCT
VF2 = (1 + 82.3kΩ / 1kΩ) * 35.55mV
VF2 = 3V

Reference Voltage:
Vref = (R2 / (R1 + R2)) * Vsupply
Vref = (5kΩ / (1kΩ + 5kΩ)) * 3V
Vref = 2.5V

​

Sampath,

One thing I noticed is that that is no burden resistor for the current transformer. I think there should be one.

For the final digital output, should this represent current of a greater than certain magnitude or zero current crossing time?     

Hi,

1.One thing I noticed is that that is no burden resistor for the current transformer. I think there should be one.

After placing the burden resistor, I am getting 35.55mV, which I have directly applied as an AC source. The amplified output is obtained correctly; however, in the comparator stage, the output is swinging between +3V and -3V. 

2.For the final digital output, should this represent current of a greater than certain magnitude or zero current crossing time?

The final digital output represents fault current detection by indicating when the current exceeds a set threshold. It does not detect zero current crossing time.

3.Is there any other method to achieve a 3V to 0V output? Also, for hardware design, are there any additional factors to consider?

Thanks for your guidance.