| 摘要 |
A method of optimizing cross current in class D amplifiers and simultaneously minimizing the harmonic distortion is provided. The method overcomes the problem of using the limited speed voltage comparators often used in cross current preventing circuits. Method embodiments are based on introducing a replica amplifier with a current sensor matched to a main amplifier. The duration of a sensed cross current within the replica amplifier is compared by a current comparator with a small enough reference current. The comparator output generates a pulse with a duration equal to the duration of the cross current event in the replica amplifier. The duration of that pulse is measured and used to generate a dead time pulse for blanking amplifier pre-driver inputs.
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