LPV7215: Does this Low voltage and low power comparator generate Square wave @ 1.8v..?

Hi Ranganathan,

of course, you must add the load currents through the feedback resistances.

Can you show a schematic of your circuit?

Kai

Hello Mani,

The comparator itself will draw 580nA steady-state, but there is also the external resistor dividers and charging current for the capacitor that will add to the supply budget.

You can make the resistors large, but you have to watch making the capacitor too small - or you have to account for stray capacitance.

Comparators also draw peak currents when the output transitions. These peak currents usually occur while the output is moving and they can be many times the quiescent current. This current gets averaged by the bypass cap, but the result is a rising average supply current vs output frequency.

What is the frequency range you are interested in? The faster you go, the more current that will be needed for the faster prop delay spec.

We have newer devices with even lower supply currents, such as the TLV7031(330nA)  or even the TLV3691 (70nA). These two both have SPICE models.

But your choices are dominated by the required propagation delay required to achieve your frequencies of interest.

Please see the following appnotes and TI Precision labs presentation:

 Relaxation oscillator circuit  Appnote TINA file: http://www.ti.com/lit/mo/sbomao3/sbomao3.zip

 2103 - Comparator Applications 3.pdf (see Maximum Toggle Frequency - Page 16)

Hi Kai and Paul,
Thank a lot for your responses.
Ok, I will try to simulate TLV7031 & TLV3691 and I will build my design based on the results soon.

FYI: My design expecting the frequency range from 10KHz to 500KHz. (at worst case 1MHz)

My major concern are really these comparators will work with 1.8 volt or not because all reference circuit (from TI) using either 3v or 5v. Kindly confirm and if you have any reference design schematic for 1.8v kindly share with me.

I will try to simulate these two comparators and and come back to you soon.

Once again thanks.
mani

Hi Ranganathan,

a maximum frequency of about 100kHz seems realistic with the TLV7031:

ranganathan.TSC

Kai

Hi Kai,
You are really a great. Thanks for your deep support.
I will go for my design then.

Thank a LOT for your extensive support regarding my question.
I'm really happy about your file, simulation result and your reply.

Once again thanks.
Mani

Hi Kai,

    I have simulated your file, but i can see new scenario.. the waveform swing top and bottom..

   Is that real scenario.. (or) for only simulation.

please find the screen print for your reference.

thanks and regards,

Mani

Hi Ranganathan,

change the scope settings:

Also set "Mode" to "Normal".

Kai