INA240: INA240

Hi Guang and Jamie,

Thanks for your response. This is Cameo Tim Wu, INA240 can support 25A, but my concern is the power dissipation on Rsense. For example, Rsense is 0.033 Ohm and pass through 25A current. the power is 25x25x0.033=20.625W. It is too high.  The resistor that much lower than 0.033 Ohm, it should not popular.  so I would like to look for hall sensor , or have any suggestion on Rsense on INA240 design?. If TI have solution, can you provide the hall sensor partNo. and spec to me? Hall sensor is no need the Rsense, right? sorry, I didn't have the design experience on high current and hall sensor, so I didn't  sure the hall sensor if can impelemt on my application and need the Rsense.

Tim

Hi Tim.

Your concern about power dissipation is valid. Fortunately, there are low value Rsense available to address it. Here is a link to what’s available on DigiKey.

A common question is how to size and choose Rsense. You may want to check out this video as it goes into more details.

You’re correct that hall sensors do not require Rsense. You can check out what’s available today here. We also have non-magnetic current sensors with integrated Rsense, such as INA253. There is a limit on maximum continuous current. If the 25A max is pulsed, then these devices may work.  

Regards, Guang

Hi Guang,

Thanks for your reply. For my application, the maximum constant current 25A will big challenge on shunt R selection. It should be lower than 0.5m Ohm, It will be expensive and long lead time. INA253 have build in one 2m Ohm Rshunt, but it look only support maixiumn 15A, right? So I would like to use hall senser. But TI hall senser only support 20A contiunuous current, right?

Tim