| 摘要 |
A circuit and method for representing in digital form information about the time and amplitude characteristic of a time-varying input signal. The time-varying input signal is delayed and the magnitudes of the time-varying input signal and its delayed version are compared to produce a digital signal representing the time characteristic of the input signal in the form of a transition in a digital output signal each time the magnitudes of the compared signals have a predetermined relationship. The predetermined relationship may be a condition of approximate equality or when the magnitude of the larger of the compared signals becomes less than the magnitude of the smaller of the compared signals. The invention also includes a circuit for outputting a digital representation of the amplitude of the time-varying input signal for each transition of said digital output signal. The disclosed circuits thus provide separate digital representations of the time and amplitude of each peak and valley of an analog or other time-varying input signal. The invention also includes an application of the analog-to-digital converter in a pitch tracking circuit.
|
