Pulse duty cycle transition moderating device
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorJoel Katz
Life of this patent
Estimating the term…
Abstract
A pulse width control circuit that narrows, then allows a gradual increase n the pulse width of the output pulses to the width of the input pulses that is activated as the pulse repetition rate of the input pulses increases. The pulse width control circuit will provide the turn-on transient and high voltage supply transient suppression for a pulsed transmitter by selectively interconnecting a pulse repetition detector and a variable pulse width generator with a combining logic circuit.
Claims6
A duty cycle transition moderating system which comprises:
- a. an apparatus input channel to receive an input pulse train having a high pulse repetition frequency region and a low pulse repetition frequency region, the transition from low to high pulse repetition frequency occurring when the pulse period becomes equal to or less than t.sub.1 when the pulse train is applied to the system said detector including means for producing a pulse of width t.sub.1 in response to the leading edge of the pulse of said input pulse train;
- b. a high repetition frequency detector in electrical connection with said apparatus input channel to sense a change of frequency of the pulses of said input pulse train from the region of low pulse repetition frequency to that of high pulse repetition frequency;
- c. a variable pulse width generator in electrical connection with said apparatus input channel and with said high pulse repetition frequency detector to produce a pulse train of pulses of narrowed, then gradually increasing width synchronous with that of the input pulse train;
- and
- d. output combining logic in electrical connection with said apparatus input channel and said high pulse repetition frequency detector and said variable pulse width generator to combine outputs thereof to produce a gradual increase of duty cycle when the input train of pulses makes a transition from the region of low pulse repetition frequency to high pulse repetition frequency.
A high pulse repetition frequency detector which senses a change in the pulse repetition frequency of an input pulse train from a low frequency state (period of pulses greater than t.sub.1) to a high frequency state (period of pulses less than or equal to t.sub.1) transmitted through an apparatus input channel which comprises:
- a. a one shot logic device having an input terminal and an output terminal said one shot logic device electrically coupled at its input terminal to said apparatus input channel and producing a pulse of width t.sub.1 in response to the leading edge of a pulse at its input;
- b. a first flip-flop logic device having an output terminal, a clock input in electrical connection with said apparatus input channel, a clock reset input and a clear input said clear input in electrical connection with said one shot device output;
- c. a second flip-flop logic device having a first output and a second output of complementary logic, a clock input and a clear input;
- d. said clock input of said second flip-flop in electrical connection with the output terminal of said first flip-flop, said clear input of said second flip-flop in electrical connection with the output terminal of said one shot logic device, said second output of said second flip-flop in electrical connection with said clock reset of said first flip-flop so that when the period of said input pulse train is t.sub.1 or less said first output of said second flip-flop is maintained, during the duration of the portion of the pulse of such period, in its high logic state and said second output of said second flip-flop is driven to and maintained in its low logic state.
Dependencies are inferred from the claim text.