L6208Q
Circuit description
Figure 21. Overcurrent protection simplified schematic
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Figure 22 shows the overcurrent detection operation. The disable time tDISABLE before
recovering normal operation can be easily programmed by means of the accurate
thresholds of the logic inputs. It is affected by both CEN and REN values and its magnitude is
reported in Figure 23. The delay time tDELAY before turning off the bridge when an
overcurrent has been detected depends only on CEN value. Its magnitude is reported in
Figure 24.
CEN is also used for providing immunity to pin EN against fast transient noises. Therefore
the value of CEN should be chosen as big as possible according to the maximum tolerable
delay time and the REN value should be chosen according to the desired disable time.
The resistor REN should be chosen in the range from 2.2 k to 180 k. Recommended
values for REN and CEN are respectively 100 k and 5.6 nF which allow to obtain 200 µs
disable time.
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