L6208Q datasheet(21/34 Pages) STMICROELECTRONICS

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L6208Q

Circuit description

Figure 21. Overcurrent protection simplified schematic

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.

L6208Q 数据表(PDF) 21 Page - STMicroelectronics