DocID024568 Rev 4

23/31

TSX9291, TSX9292

Application information

31

4.8

High side current sensing

TSX9291 and TSX9292 rail to rail input devices can be used to measure a small differential

voltage on a high side shunt resistor and translate it into a ground referenced output voltage.

The gain is fixed by external resistance.

Figure 41. High side current sensing configuration

Equation 8

Equation 9.

Equation 9

With the TSX929x series, the high side current measurement must be made by respecting

requires a higher common voltage, please refer to the TSC high side current sensing family.

+

-------------------------⎠

⎞ 1

----------

+

⎝⎠

⎛⎞

–

⎝

⎛

×

+

-------------------------

⎝⎠

⎛⎞

1

----------

+

⎝⎠

⎛⎞ I

----------

+

⎝⎠

⎛⎞

–

–

×

+

=

-------⎠

⎞

⎝

⎛

×

-------

+

⎝⎠

⎛⎞

–

×

+

=