摘要 |
In an output stage for a hearing aid, a reduction in the power consumption for low level input signals is obtained through the use of a time-averaging output driver, whereby the output transducer is subject to three different conditions of operations, this being obtained through the generation of three-state control signals for control of an H-bridge. The three-state control signals are generated through the use of a time-averaging device whereby the two-level output of a single bit Sigma-Delta modulator is transformed to a set of control signals that, at any given time, can assume one of three states. In a preferred embodiment the time-averaging device is a delay.
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