Saturation problem

AN4366

6/14

DocID025330 Rev 1

Negative Vos (Vos of the TSC103 = -1.1 mV)

When it is necessary to measure 1 A, the voltage output of the TSC103 using equation 2 is:

Vout = (1 A * 0.5 mΩ + 1.1 mV) * 100 = 160 mV. This value is acceptable as it is above the

maximum Vol of the TSC103.

Positive Vos (Vos of the TSC103 = +1.1 mV)

When it is necessary to measure 1 A, the voltage output of the TSC103 using equation 2 is:

Vout = (1 A * 0.5 mΩ -1.1 mV) * 100 = -60 mV. As the TSC103 is powered in single supply

the output in this case is saturated and Vout = Vol. In this case, a current lower than 4.7 A

(see equation 3 below), cannot be measured correctly by the current sensing due to the

Vos and Vol limitation.

Rshunt