초록 ▼

An improved direct digital frequency multiplier that multiplies input frequencies by a factor equal to the number of comparators in the circuit divided by two. The circuit includes a sensing stage, a ramping stage, a storage stage, a comparison stage and a logic stage. A signal containing the freque

An improved direct digital frequency multiplier that multiplies input frequencies by a factor equal to the number of comparators in the circuit divided by two. The circuit includes a sensing stage, a ramping stage, a storage stage, a comparison stage and a logic stage. A signal containing the frequency to be multiplied is input to the sensing stage, which determines the frequency of the signal and outputs timing signals to the rest of the circuit. Coinciding with the period of the input signal, ramping voltages are generated, whose peak voltages are sampled and held for a specific time. The linearly ramping voltages are compared with the peak voltages and the comparison stage outputs voltage spikes to the logic stage. The logic stage combines the outputs from the comparison stage, and outputs a square wave signal possessing the appropriate multiplied frequency.

대표청구항 ▼

A frequency multiplier, comprising: input means, connected to an input signal whose frequency is to be multiplied; sensing means, coupled to said input means, for sensing the frequency of said input signal; dual ramp generator means, coupled to said sensing means, for producing a sawtooth voltage si

A frequency multiplier, comprising: input means, connected to an input signal whose frequency is to be multiplied; sensing means, coupled to said input means, for sensing the frequency of said input signal; dual ramp generator means, coupled to said sensing means, for producing a sawtooth voltage signal on alternative halves of a period of said input signal thereby providing a frequency of at least twice the input frequency; storage means, coupled to said ramp generator means, for storing a peak voltage of said sawtooth voltage; comparison means, coupled to said ramp generator means and said storage means, for comparing an instantaneous magnitude of said sawtooth voltage with said peak voltage and creating an output voltage transition; and logic means, coupled to said comparison means, for producing an output signal whose frequency is a desired multiple of said input signal frequency as a function of the magnitude of said output voltage transition of said comparison means.