• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 47 subscribers
  • Views 1473 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AMC1301: Input-Referred Noise Density vs Frequency

Hiroshi Takahashi
Prodigy 210 points
Part Number: AMC1301

I have some question about AMC1301 Input-Referred Noise Density vs Frequency.

datasheet says in below.

I think that this data condition is VINP = VINN = GND1( VINP - VINN = 0V), fIN = 0 Hz.

Is my perception recognized?

If VINP - VINN is not 0V, 　Does AMC1301 「　Input-Referred Noise Density vs Frequency 　」 characteristic change ?

for exmaple,

VINP- VINN = -0.2V、

VINP- VINN = -0.1V

VINP- VINN = -0.2V

VINP- VINN = +0.2V

If  AMC1301 「　Input-Referred Noise Density vs Frequency 　」 characteristic change,　I want to know how it changes.

If it change,  May I get some data as Figure 33?( change VINP-VINN= -0.2V, -0.1V, +0.1V, +0.2V )

Kind regards,

Taka

  • 0
    TI__Guru**** 180931 points
    Hi Taka-san,

    Your assumption is correct; the plot of Figure 33 in the AMC1301 datasheet is with shorted inputs. This is a common practice means to measure the input referred noise. I do not have the data that you are asking for, but if you need some samples to try implementing the AMC1301 in your existing application, I'd be happy to arrange getting you some parts to play with.
  • 0 in reply to Tom Hendrick
    Prodigy 210 points
    Hi Tom,

    Thank you for reply.
    If AMC1301 condition is not VINP- VINN = 0V,
    In principle, Does AMC1301　Input-Referred Noise Density vs Frequency　increase than condition VINP- VINN = 0V ?
    now, I design isolated DC voltage, AC voltage, DC current, AC current measurement circuit.
    I think that I use AMC1301 for it.
    It needs high precision measurement.
    I want to know how much "Input-Referred Noise Density vs Frequency" is a problem in actual use.
    in datasheet Figure 33, 　Below 100 kHz it is less than 200 nV/√Hz.　
    for example, when VINP - VINN is 0.2V, Is there a possibility of 1uV/√Hz at 100 kHz or less?

    Regards,　

    Taka
  • 0 in reply to Hiroshi Takahashi
    TI__Guru**** 180931 points
    Hi Taka,

    Input-referred noise is a figure of merit that shows how much 'noise' is inherent in the device itself. It has to do with the architecture of the device, it’s internal transistors, resistors, etc. Figure 33 goes through the output bandwidth of the AMC1301. This noise, would be added to any noise associated with a back end ADC that would be used to digitize the AMC1301 output.