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DRV5053: Looking for a magnetic field sensor that can handle 10 teslas

Jason Chan42
Intellectual 360 points
Part Number: DRV5053
Other Parts Discussed in Thread: DRV5055, DRV5056, DRV5055-Q1

I'm working on a project to sense magnetic fields and record the field strength. Previously, I used the HMC5883L magnetometer shown in the link below to measure the field through I2C:

www.adafruit.com/.../1746

However, the magnetic field that we're trying to sense is 10 teslas, which the HMC5883L cannot handle without saturating. Once the device saturated, we had to reset it, and this occurred every hour. So I'm looking for a replacement.

I found one product, the DRV5053, and I was wondering if it can handle 10 teslas safely. The datasheet showed that it can handle an unlimited magnetic flux density, but I wanted to ask to make sure. Also, are there any other suitable products that can measure the magnetic field and communicate to a small single-board computer through I2C? The DRV5053 doesn't have that capability, and it is definitely necessary in order to take and record measurements through my computer, a Raspberry Pi Zero. To be clear, I want to measure and record the magnetic field so that I can visually graph it and monitor its intensity.

Also, would the DRV5055 or DRV5056 be worth considering here? Both products seem relatively new, and I'm worried that they might not work in a 10 tesla field.

  • 0
    TI__Mastermind 20985 points
    Hi Jason,

    The DRV5055 and DRV5056 are definitely the better choice. The A4 versions can measure up to about 0.17 T; you can apply stronger fields, but they won't be measurable. To convert to I2C, you could use an MSP430.

    Best regards,
    RE
  • 0 in reply to RE
    Intellectual 360 points
    Thank you for your reply. I looked into the DRV5055, and like you said, it can measure up to 0.17 T, but if we applied a stronger field, say 10 T, would it saturate the device? Do you have any devices that can measure 10 T safely without saturating? That's the main issue we had with the HMC5883L. Once we found that the devices saturated, we had to reset them by cutting power to them for a moment. We would prefer to not have to do that so often or not at all if possible.

    Also, according to the datasheet, it outputs a voltage based on various environment and operating parameters according to 7.3.2, but to convert it to I2C, that's what the MSP430 is for? How could we do that with the microprocessor?

    Alternatively, if I2C proves to be too big an issue, is it possible to hook up the DRV5055 to something like an Arduino as an analog input? That way, we can just write code to read the voltage and convert it to the appropriate reading in software. Also, while the DRV5055 can detect the strength of the field, how can we get the direction of the magnetic field as well? What would that require, to get the direction?
  • 0 in reply to Jason Chan42
    TI__Mastermind 20985 points
    Is your goal to measure the field up to 10 T, or do you only need to measure <0.17 T and you want to avoid resetting the device if a very strong field is applied? The DRV5055 doesn't need to be reset in any way if you apply a strong field.

    If you need to measure 10 T, I recommend looking into a 4-pin Hall element device, such as one made by AKM.

    I'm not an MSP430 expert, but if you google "MSP430 I2C" the first result is an app note that has info on that.

    Finally, to do multi-axis sensing with the DRV5055, because this sensor measures magnetic flux density in 1 axis, you'll need to use multiple devices oriented in different directions. For example, 2 TO-92 devices that are rotated 90 degrees plus 1 SOT-23 device will provide 3 axis data.

    Best regards,
    RE
  • 0 in reply to RE
    Intellectual 360 points
    Thank you for your reply. After much discussion with the team, we came up with a guideline in regards to the stability that we need for our magnetic field sensor. It has to be stable within 2 gauss (0.2 milli-teslas) or more. Our magnetic field sensor doesn't have to measure up to 10 teslas, 0.17 teslas is fine, but it has to remain stable within the 10 tesla environment without saturating and requiring a reset.

    You mentioned that the DRV5055 fits those requirements. I looked at the datasheet and while it seems like a wonderful product, the issue is that it is not commercially available yet. In light of this, would the DRV5053 work as well since it is commercially available? How high of a magnetic field can it measure up to? Also, if it will work, do you have any military-grade variants of the sensor available for purchase? It is possible that the sensor be bombarded with radiation, so we were hoping that a military-grade version of the sensor would withstand such a beating.

    Also, as the DRV5053 is an analog sensor, it won't work directly with a Raspberry Pi. I did some research, and while the Pi is good for digital signals, it doesn't play well with analog signals. I looked at the MSP430 that you suggested, but we don't really need all that. Putting aside I2C for a moment, what are some other ways that is recommended for readout of the DRV5053? Using an ADC converter comes to mind, but do you have any recommended readout suggestions for the sensor?
  • 0 in reply to RE
    Intellectual 360 points
    More specifications were obtained from the team so I need more information about parts, as shown in the reply below.
  • 0 in reply to Jason Chan42
    TI__Mastermind 26650 points
    Hello Jason,

    I will be filling in for RE and I'm excited to help. This sounds like a cool project.

    When you say stable within 2 gauss or more, do you mean you want to be able to measure 2 gauss? If this is the case, then DRV5055 will be the better option over DRV5053 since it has less noise. Consider comparing DRV5053VA and the DRV5055A1. You can still request samples for the DRV5055 while still in the evaluation phase of your project. You also can order preproduction DRV5055-Q1 parts from distributors. See the "order now" tab on the product pages.

    For DRV5053VA powered at 3.3V:
    sensitivity = -90mV/mT
    VN = 44mVpp = output-referred noise
    Vsignal = -90mV/mT * 0.2T = -18mV

    For DRV5055A1 powered at 5V:
    sensitivity = 100mV/mT
    VN = 12 mVpp
    Vsignal = 100mV/mT * 0.2mT = 20mV

    As you can see the DRV5055A1 will generate a signal above the noise floor. It may be possible that you could use the DRV5053 and incorporate digital averaging or analog filtering on the output to average out the noise and better determine the DC Vsignal.

    Both DRV5055/DRV5053 will not require a reset if driven exposed to 10T environment.

    We do not have any military grade nor radiation-hardened Hall-Effect sensors. We cannot specify any characteristics about the DRV5055/DRV5053 when in the presence of heavy radiation. You can read more about what radiation hardened/space products we have here:
    www.ti.com/.../enhanced-products.html

    For the best ADC for this case, I recommend posting to the precision data converters forum here:
    e2e.ti.com/.../

    Sincerely,
    Peter Iliya
    Current Sensing Applications
  • 0 in reply to Peter Iliya
    Intellectual 360 points
    Dear Mr. Iliya,

    Thank you for your reply. Your post has helped me out greatly, and I will speak to my team soon and present them with this information to decide on where to go from here.

    Unfortunately, in regards to ordering samples, I'm afraid I cannot. I work at a university, and I am not a student. Everyone here has a '.edu' email address, and this cannot be changed, and when I tried to request samples, TI said that even though I am not a student, I cannot order samples due their email address policy and the fact that I have that '.edu' suffix at the end of it. Nevertheless, I will let my team know that we can purchase DRV5055 parts through the link above.

    My team has also introduced the need to include an accelerometer into the 'sensing kit', so I'll have to figure out a way to work that in. Again, this is something I'll have to speak to my team about before we decide on a course of action. Until then, thank you for your help.
  • 0 in reply to Jason Chan42
    TI__Mastermind 26650 points

    Jason,

    The part was released to market very recently so the device should be getting into distributor inventory pretty soon (a week or so). Also, if you verify the answers I have been considering as "resolved" then you should get free shipping on samples.
     
    Peter Iliya
    Current Sensing Applications