Digitally controlled pulse generator

Claim 2

A pulse generator comprising a digital storage means for storing a predetermined number, a recirculating counter, means for sequentially varying the state of said counter at a selected frequency, said recirculating counter providing a first output signal each time said counter recycles to a zero count, coincidence detecting means connected to said digital storage means and said recirculating counter for providing a second output signal when the count is said counter coincides with the number contained in said digital storage means, and a bistable means having a first input connected to said coincidence detecting means and a second input connected to said recirculating counter, said bistable means being responsive to each first output signal from said recirculating counter to switch to its first stable state and responsive to each second output signal from said coincidence detection means to switch to its second stable state to provide a pulse output signal whose duty cycle satisfies the equation: Z (Y -X)/ Y where Z represents the duty cycle, X is the number stored in the digital storage means, and Y is the number representing the maximum count of the recirculating counter.

Claim 3

A pulse generator as defined in claim 1 wherein said bistable storage means comprises a reset-set flip-flop having its reset input connected to the output of said recirculating counter and its set input connected to said coincidence detection means.

Claim 4

A pulse generator as defined in claim 2 wherein aid sequential varying means comprises a clock pulse source.

Claim 5

A pulse generator as defined in claim 1 wherein said recirculating counter includes a plurality of stages with a parallel number output and said memory circuit includes a plurality of stages equal to the number of stages in said recirculating counter having a parallel number output, each of the counter stages providing a complementary number output.

Claim 6

A digitally controlled pulse generator whose duty cycle may be readily and accurately varied comprising a recirculating counter having a plurality of parallel binary number outputs B1, B2, B3 ... BN, where the subscripts indicate the order of binary number bit, means for sequentially varying the count of said counter at a selected frequency, said counter providing a first output signal each time the counter recycles to a zero count, a memory circuit having a plurality of parallel binary number outputs B1, B2, B3 ... BN, coincidence detection means connected to said recirculating counter and said memory circuit for continuously monitoring the parallel number outputs indicated by said counter and said memory circuit and providing a second output signal when said number outputs coincide, and a bistable storage means having first and second stable states connected to said recirculating counter and said coincidence detection means, said bistable storage means being set in its first stable state in response to each first output signal produced by said recirculating counter and in its second stable state each time said coincidence detector provides a second output signal to provide a pulse output having a duty cycle satisfying the equation: Z (X - Y)/ Y where Z represents the duty cycle, X is the number stored in the memory circuit, and Y is the number representing the maximum count of the recirculating counter.

Claim 7

A digitally controlled pulse generator whose duty cycle may be readily and accurately varied comprising a recirculating counter having a plurality of parallel binary number outputs B1, B2, B3 ... BN, where the subscripts indicate the order of binary number bit, means for sequentially varying the count of said counter at a selected frequency, said counter providing a first output signal each time the counter recycles to a zero count, a memory circuit having a plurality of parallel binary number outputs B1, B2, B3 ... BN, coincidence detection means connected to said recirculating counter and said memory circuit for continuously monitoring the parallel number outputs indicated by said counter and said memory circuit and providing a second output signal when said number outputs coincide, and a bistable storage means having first and second stable states connected to said recirculating counter and said coincidence detection means, said bistable storage means being set in its first stable state in response to each first output signal produced by said recirculating counter and in its second stable state each time said coincidence detector provides a second output signal to provide a pulse output having a duty cycle satisfying the equation: Z (X - Y)/ Y where Z represents the duty cycle, X is the number stored in the memory circuit, and Y is the number representing the maximum count of the recirculating counter.

Claim 8

A pulse generator as defined in claim 5 wherein said bistable storage means comprises a set-reset flip-flop with its set input connected to said coincidence detector and its reset input connected to the last stage of said recirculating counter.

Claim 9

A pulse generator as defined in claim 6 wherein said sequential varying means comprises an adjustable frequency clock pulse source.

Claim 10

A pulse generator comprising a digital storage means for storing a predetermined number, a recirculating counter, means for sequentially varying the state of said counter at a selected frequency, said recirculating counter providing a first output signal each time said counter recycles to a zero count, coincidence-detecting means connected to said digital storage means and said recirculating counter for providing a second output signal when the count in said counter coincides with the number contained in said digital storage means, and a bistable means having a first input connected to said coincidence detecting means and a second input connected to said recirculating counter, said bistable means being responsive to each first output signal from said recirculating counter to switch to its first stable state and responsive to each second output signal from said coincidence detection means to switch to its second stable state to provide a pulse output signal whose duty cycle varies as a function of the ratio of the number in the digital storage means to the maximum count of the recirculating counter.

Claim 11

A pulse generator comprising a digital storage means for storing a predetermined number, a recirculating counter, means for sequentially varying the state of said counter at a selected frequency, said recirculating counter providing a first output signal each time said counter recycles to a zero count, coincidence-detecting means connected to said digital storage means and said recirculating counter for providing a second output signal when the count in said counter coincides with the number contained in said digital storage means, and a bistable means having a first input connected to said coincidence detecting means and a second input connected to said recirculating counter, said bistable means being responsive to each first output signal from said recirculating counter to switch to its first stable state and responsive to each second output signal from said coincidence detection means to switch to its second stable state to provide a pulse output signal whose duty cycle varies as a function of the ratio of the number in the digital storage means to the maximum count of the recirculating counter.

Claim 12

A pulse generator as defined in claim 8 wherein said digital storage means and said recirculating counter each provide a plurality of parallel binary number outputs.

Claim 13

A pulse generator as defined in claim 9 wherein one of said plurality of binary number outputs is the complement of the direct output.