• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 46 subscribers
  • Views 146 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.

INA296A: Power Consumption

Aditya Kumar Singh
Prodigy 30 points
Part Number: INA296A

Tool/software:

Hi E2E Team,

INA296A is planned to be used for current measurement with shunt resistor. Supply voltage is 5V and both reference pins are planned to be connected with GND. As per calculation the max. o/p voltage will be around 2.3V.

As per below image, the o/p current @2.3V ~ 12mA and Iq is 3.2mA max.

So, for total power consumption @5V power rail shall we consider 12mA + 3.2mA  or only 3.2mA?

Regards,

Aditya

  • 0
    TI__Mastermind 34080 points

    Hi Aditya,

    The operating quiescent current is 3.2mA max over temp range.

    The curve you quoted is output voltage versus output current. The output current is not part of operating current.

    Regards

    Guang

  • 0 in reply to Guang Zhou
    Prodigy 30 points

    Hi Guang,

    Thankyou for your response.

    As per my understanding, the Iq ~ 3.2mA (max) is the current consumed by the IC internal ckt. during active mode.

    Also, the o/p current will be drawn from supply voltage (Vs) only because that is the only voltage source and there should be some relation between i/p supply current and o/p current based on internal ckt. which is generating the o/p voltage and current. Please let me know in case of any discrepancy in the understanding.

    Intension here is to calculate the worst case power consumption of the IC. Is 3.2mA@5V (Vs), the worst case power consumption for INA296A? Because as per figure 6-23 of the datasheet, IC will provide ~12mA of o/p current @2.3V. This current will be drawn from the i/p power supply only. Shall we not add this power along with Iq for worst case power consumption?

    Regards,

    Aditya

  • +1 in reply to Aditya Kumar Singh
    TI__Mastermind 34080 points

    Hi Aditya,

    The short answer is – it depends.

    The device has the capability to source/sink 10’s mA of current. But whether that amount is consumed by the downstream circuitry is entirely decided by the board designer. Typically the output current is limited to a very small number, simply to keep the output voltage at a reasonably accurate level. In this situation, the output current can be ignored in the calculation.

    However if you expect there to be a large output current, maybe comparable to the device quiescent current, then it should be included as you described.

    Regards

    Guang