摘要 |
<p>Ascertaining through integration a bias calibration level for a current control loop of a driver motor of a tape drive. The driver motor includes a current controller having as inputs a demand signal, a bias signal, and a feedback signal. The current controller includes an integrator coupled to the output. The method includes setting the demand signal to a zero current level, setting the bias signal to a level that substantially prevents the integrator from driving itself high, stepping down the bias signal to form a stepped down bias signal, measuring a sense parameter at the output of the current controller, determining whether the sense parameter is high for the stepped down bias signal, and setting the bias calibration level to a level sufficiently above the stepped down bias signal such that the integrator is not driven high when the demand signal is set to the zero current level.</p> |