In PWM mode, the upper driver is turned-off when the motor current reaches the intended value. An internal One-Shot pulse determines the lenght of time the upper driver stays off before turning on again. The pulse width, and thus the cutoft time (toft), is configurable by means of the external RC network connected to the RC pin. (see Fig. 2). The resistor at the RC pin, therefore determines both the driver output slew-rate during linear mode and the off-time constant during PWM. The lower driver is always on during PWM mode of operation; an on-chip 2ys mask can prevent the beginning of a new cutoff time because of transient current spikes caused by the upper drivers turn-on.
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| | 7 | | |
| | | | r-ttoMriz V ra ra - 5 \1 |
| | | | Pin= 400mW |
| | | | ZG=ZL=50 Q |
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