• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • 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.

INA200 - Any leak from Vs supply when no load supply connection ?

Kawai
Guru 19785 points
Other Parts Discussed in Thread: INA200, INA213, INA282, INA201

Hello Team,

Could you please allow me to ask you if there is a possibility that VIN+ or VIN- having some voltage monitored due to leak from 5V supply ?

In our customer application, the "load supply" in the following schematic would be some kind of device which state could be undefined during power up. INA200 power supply is powered up first.

Best Regards,

Kawai

Best Regards,

Kawai

  • 0
    TI__Expert 4595 points
    Hi Kawai,
    What kind of issue are you facing? Can you please share some information regarding your application.
  • 0 in reply to Rabab Itarsiwala
    TI__Genius 14825 points

    I tried one unit in the lab just now and found that with 5V supply and nothing on the inputs, I measured roughly 1.6V on VIN+ and VIN-.  I swept the Vs around from 3 to 7 and saw the voltage on the inputs change from roughly 1.5V to 1.7V.  Also, there was a slight potential difference (3-5mV) between VIN+ and VIN- and that created a voltage on the output of 60-100mV.  I don't know if every device will perform this way but I suspect that because this mode of operation is not intended, it could happen, or be better or worse.

  • 0 in reply to Jason Bridgmon
    Guru 19785 points
    Hello Jason-san, Rabab-san,

    Thank you for your support. It seems this device is not good at monitoring low Vsense voltage as it having a large offset (error). It seems INA213 would be much better. Do you have any other device recommendation ?

    Customer wants to monitor current accurate even when the load or load supply in the above schematic is dis-connected.

    Best Regards,
    Kawai
  • 0 in reply to Kawai
    TI__Genius 14825 points

    The INA213 and the INA282 both are great parts with a gain of 50 that can measure low Vsense voltages better than the INA201.

    Regarding floating inputs - this is really outside the intended use case of the parts.  We always expect them to be connected to something.  There are resistive paths through any device that will bias floating pins to some level, so to avoid that, keep them tied to a known node.