Current Measurement Part number(Range 4mA to 500mA)

Hi Siva,

We would need more information to provide a recommendation.

1. What is your supply voltage?

2. What is the Common Mode Voltage Range?

3. Do you need a analog or digital output current shunt monitor?

4. What type of accuracy you are looking for?

5. What’s your application? Do you need an alert pin? you need to measure bidirectional currents?

Hi Mayrim ,

First of all thank you for your quick reply.

my answer for your questions

1. What is your supply voltage?

power supply range (±2.5 V to ±18 V)

2. What is the Common Mode Voltage Range?

 ±500 V common mode

±500 V differential mode

3. Do you need a analog or digital output current shunt monitor?

analog output

what is difference between analog or digital output current

4. What type of accuracy you are looking for?

Measurement error: f = ± 1% o. R. ± 1mA"

"Mains 50mA +/- 5%
Battery 25mA +/- 5%" "Mains 50mA +/- 5%
Battery 25mA +/- 5%" "Mains 50mA +/- 5%
Battery 25mA +/- 5%" "Mains 50mA +/- 5%
Battery 25mA +/- 5%" "Mains 50mA +/- 5%
Battery 25mA +/- 5%" "Mains 180mA +/- 10%
" "Mains 500mA +/- 15%

5. What’s your application? Do you need an alert pin? you need to measure bidirectional currents?

   Coil Current measurement application(current is varying from 0 to 500mA ,it means it is looking like a pulse current i want measure this pulse current )

   alert pin is optional 

Below circuit is for your reference .

i want replace below Part number  with TI part number.

The below circuit, the problem is measuring only constant current i want measure pulsating current also.

Thanks,

Siva

Hi ,

I need maximum current measurement of this part number INA226

Hi Siva,

None of our current shunt monitors will work for your application, we do not support common mode voltages that high. I would suggest you take a look at difference amplifiers such as INA149.

I will move your question to the op-amps group, they will be able to suggest a suitable device for your application.

Siva,

There are a few paths for this. 

We do have the INA117 which is similar to your schematic. I can direct you to the group responsible for this product and they can assist.

We also have the Isolation amplifiers like the AMC1100 and the AMC1200 and AMC1301 and if this is your path I can direct you to the group responsible for those products.  

Also we have magnetic sensing products like the DRV421 and the DRV425 that integrate a flux gate sensor.  With the ranges you are discussing there would need to be some magnetic shielding involved and an magnetic core.  I work on these devices and can help you get this done in the magnetic domain.  

Please let me know which path you are most likely to proceed so that we can get you the correct assistance.

Hi Javier,

what is the maximum current measurement possible of above part numbers

This part have capability to measure both DC,Pulsating current??

My application is i want measure both DC and pulsating current range(10mA to 600mA).

In my application Current is varing from 10mA to 600mA,thing is we are able to measuring DC current from the above circuit(ref).

we want measure pulsating current also is it possible to measure using this part numbers.

pulsating current like this 0 to 176mA,0to 176mA,0 to 176mA.............

Hello Siva,

The maximum current for the devices in the Rshunt based will be determined by the gain and the Rshunt value.  In the fluxgate based devices the mechanical construction will determine this but normally for the DRV425 use you would just use the equation of B = µ0*I / (2πr) and the full scale of the DRV425 is 2mT.  The DRV421 uses a feedback with a magnetic core and can measure the higher currents.  The issue will not be maximum current with the fluxgate devices but rather shielding external unwanted magnetic fields.

All devices will measure the DC and pulsating current the issue is the accuracy.  If bandwidth of each part will tell you how good the devices can respond.  During pulsating currents the bandwidth would need to be larger to get accurate numbers quickly after the pulse.  Datasheets normally have large signal step response plots that will show you the typical response to a step input.  

The INA117,  INA146 and INA149 have a Common mode voltage that does not work for the 500V you mentioned.

So I would ask you to look at our two options and there tradeoffs.  If you think Isolation amplifiers are your best option I will direct you to that group.

The Isolation amplifiers which require two supplies.  One at the high side and another with the low side.  There are a few TI Designs you can view for reference.  Just got  to the AMC1100, AMC1200, or AMC1301 product page and go to the "Tools & Software" Tab.  Here is one from the AMC1200 page (AMC1200 TI Design)

The magnetic devices need magnetic shielding and mechanical design of a magnetic core/concentrator. The DRV425 has lower bandwidth of 47Khz and the DRV421 response will be determined by the magnetic core and the differential amplifier which has a bandwidth of 2Mhz.