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INA303: Use of a (INA300-series) current-sense amp (high-side) for a 4-20mA current loop?

Part Number: INA303
Other Parts Discussed in Thread: TPS2661, INA301, INA168, INA186, TLV7081

Hello,

I am toying around with local panel indication for 4-20mA current loop devices. I saw TI has pre-production (TPS2661 4-20mA protection ICs) but I'm not really interested in messing around with products I can't even source yet. Additionally, I am more-so interested in using a current sense amp to provide high-level data on current loop status (OK/offline/fault) etc. 

I napkin-crunched the numbers for the INA301 and I theoretically should be able to detect currents down to 4mA.. but it's close and also unclear*. (* = the datasheet technically says for sensing a 10A max current, the max Rsense value is 2.0mOhm.) 

Let's say I have a 4mA current across a 100mOhm shunt, my min sense voltage @ a gain of 100 is 40mV.

My process loop is going to 9/10 times "rest" very low at 4.5mA. So, I'd like to scale the output to "trip" in an over-current condition at 30mA. It seems though this lineup of current-sense amplifiers is designed for larger current loads (process controls/motors etc.) so I wanted to see if anyone from TI could weigh-in if this type of use case is outside the scope for this particular lineup of products. Ideally this is a very-cost sensitive application and I do not need the ultra-high precision of more pricey picoamp capable devices.

Thanks,

Matt

--EDIT--

I should probably also mention my system voltage is 12Vdc.