摘要 |
A driver for driving a load over a transmission line, such as driving the magnetic head of a hard disk drive. The driver includes a signal switch for switching the signal to the load during a signal period, and a boost switch for boosting the signal during a boost period, so as to decrease rise time of the signal at the load by deliberately injecting an overshoot. A switchable protection device protects the signal switch and the boost switch. The protection device includes a reflection-suppression switch which is pulsed during a time corresponding to the expected return of a reflection corresponding to the overshoot signal, so as to force the protection device into saturation mode. Since the protection device is in the saturation mode during the return reflection of the boost signal, the returned reflection sees a matched impedance and thus reduces a re-reflection back to the load.
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