INA240-Q1: Settling time limits - Phase difference measurement

Naveen Sankaran

Part Number: INA240-Q1

Hi,

I am using the INA240A1QPWRQ1 to measure the current through a coil, in a sensor design. To calculate the tolerance limits of the current measurement, I would like to know the min-max values that are possible for the amplifier. It is not mentioned in the datasheet.

The reason is, the phase difference between the input and output of the amplifier is important for the EOL testing of the sensor. Any help will be much appreciated!

over 2 years ago

0 Carolus Andrews over 2 years ago

TI__Mastermind 23015 points

Naveen,

When you say phase differences, are you referring to the propagation delay between the input and the output for the device? We show this in figure 7-20 of the datasheet in the form of a step response, but we do not publish any minimum maximum limits for this. These graphs demonstrate typical performance.

0 Naveen Sankaran over 2 years ago in reply to Carolus Andrews

Prodigy 130 points

Hi Carolus,

I am referring to the propagation delay, yes. I did see the step response graph, but I wish to know the minimum and maximum possible values, at least from the internal tests from TI.

The INA is used to measure the current through a coil, which is supplied by an AC @90 kHz. Hence, it will be of great help if we know these limits. It can help us improve our internal testings.

Best Regards,

Naveen.

0 Carolus Andrews over 2 years ago in reply to Naveen Sankaran

TI__Mastermind 23015 points

Naveen,

Let me check with our team and see if this is something we can share. I, or Guang will respond back most likely Tusday of next week due to the Monday holiday here in the US.

+1 Guang Zhou over 2 years ago in reply to Carolus Andrews

TI__Mastermind 34660 points

Hi Naveen,

Because it is only a characterized parameter, there are no min/max limits for propagation delay. However simulation indicates that the delay variation is under 1.5uS.

Sometimes a ±20% rule can be adopted in order to get an estimated min/max for these parameters.

Regards, Guang

0 Naveen Sankaran over 2 years ago in reply to Guang Zhou

Prodigy 130 points

Hi Guang,

Thank you for the information. This information already helps me. Thanks again to Carolus!

Best Regards,
Naveen.

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INA240-Q1: Settling time limits - Phase difference measurement