TPS25940: imon accuracy

David Mckinney

Part Number: TPS25940

I would like to use the imon feature at lower current levels, below 100mA, like 10mA. Can you advise if there are any restrictions on use from 0-100mA and what the linearity and accuracy would be at 10mA-100mA? Is it still approximately 8% in the low end of the current range?

over 6 years ago

0 Rakesh over 6 years ago

TI__Guru** 105361 points

Hi David,

Thanks for reaching out!

<100mA, the offset current dominates. So, you can measure something from 100mA. On limited sample data, we observed accuracy of around 40% at 100mA and 15% at 300mA.

What is the application use and EE?

Best Regards,

Rakesh

0 David Mckinney over 6 years ago in reply to Rakesh

TI__Expert 6810 points

Hi Rakesh;

The application is for current control in a battery charger application, and the EE is a 2S battery charger.

Can you give me more information on the accuracy for lower currents like 50mA, 20mA and 10mA? Is there any characterization data available from IC qualification?

0 Rakesh over 6 years ago in reply to David Mckinney

TI__Guru** 105361 points

Hi David,

Thanks for the information.

The IMON is characterized only between 1A to 5A range. However, with reduced accuracy it can be used up to 100mA current monitoring. Below that the device offset current dominates; for example at no-load you would see IMON current equivalent to 60mA. This device is not suitable for <100mA current measurements.

Best Regards,

Rakesh

Power management

Power management forum

TPS25940: imon accuracy