DocID031065 Rev 2

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STSPIN820

Functional description

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The choice of the sense resistors value must take into account two main issues:



The sensing resistor dissipates energy and provides dangerous negative voltages on

the SENSE pins during the current recirculation. For this reason the resistance of this

component should be kept low (using multiple resistors in parallel will help obtaining

the required power rating with standard resistors).



The lower is the RSNS value, the higher is the peak current error due to noise on the

VREF pin and to the input offset of the current sense comparator: too small values of

RSNS must be avoided.

Figure 5. PWM current control sequence in mixed decay (DECAY = '0')

Note:

When the voltage on the SNS pins exceeds the absolute ratings, fault condition is triggered

and the EN\FAULT output is forced low.