SU801225A1 - Pulse-phase detector - Google Patents

Description

The invention relates to a pulse technique and can be used in frequency tuning systems.

Known impulse-h) detectivo consists of two pulse generators, a phase-pulse splitter, an additional trigger, one of the codes of which is connected to the output of the first of the mentioned pulse generators, and the second input is connected to one of the phase-4 outputs € an impulse splitter, the other two outputs of which are connected to the corresponding inputs of the elements; And and OR, and the input is connected to the output of the second generator. The output of the additional trigger is connected to the BTopbnvi input of the element I. The output of the first pulse generator is connected to the second input of the element OR. The outputs of the elements AND and OR, are connected to the inputs of the main trigger l.

A disadvantage of the known device is the presence of a comparison frequency at the output.

The closest to the proposed technical entity is a device containing a trigger, the first input of which is connected to the input of a sawtooth generator and a signal source, the second input through a remote element to the synchronization source and the first input of a coincidence element, the second input of which is connected to trigger output, and the output is to the first input of the key

O of the element whose second input is connected to the output of the sawtooth generator.

However, the known device has insufficient functional reliability.

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The purpose of the invention is to enhance functionality and enhance. noise immunity.

The goal is achieved by the fact that a device containing two pulse generators, a trigger, the first input of which is connected to the first input of the sawtooth generator, the output of which is connected to the first input of the electronic key, the delay element and the element And the first input of which is connected to the first generator pulses, and the output is with the second input of the electronic key, a charge capacitor and a phase-pulse splitter are inputted, the input of which is connected to the output of the second pulse generator, the first output is connected to the first input of the trigger a second output with a second trigger input, a third one whose input is connected to the output of the first pulse generator, and an output to the second input of the sawtooth generator and an input of the delay element whose output is connected to the second input of the And element, the charge capacitor is connected to the first input of the electronic key, and the second plate is connected to the common bus. FIG. 1 depicts a structural. electrical circuit of the device; in fig. 2 is a time chart illustrating his work. The pulse-phase detector contains generators 1 and 2 pulses, a phase-pulse splitter 3, trigger 4, sawtooth generator 5, charge capacitor 6, electronic switch 7, delay element 8 and element I. I. First and second trigger inputs 4 are connected through the splitter 3, to the output of the generator 1, the third input to the generator 2 and through element 9 I and to the first input keys 7, and the output through the element 8 delay to the BTopWviy input of element 9 I and directly to the first input of the generator 5, the second the input of which is connected to the first input of the trigger 4, and the output with - a second input key 7 and a condenser 6. The device operates as follows. Let us consider two modes of operation (1 and 1G, Fig. 2), which differ in the time of arrival of the pulse from generator 2. 1. Pulses from generator 2 are ahead in time from pulses from one output of the decoupler 31 and lag behind pulses from the other output of the splitter 3 Ug (I Fig. 2), In this case, the pulses (J arriving at the input of the trigger 4, transfer it to the state when the starting pulses begin to flow to the input of the generator 5 from the output of the trigger 4 and. On the capacitor 6, the voltage Ug starts to change with that corresponds to the working area b pulse-phase detector characteristics UT pulses coming from oscillator 2 to trigger input 4 transfer it to the initial state, the triggering pulses end, causing the charge of the capacitor 6 to stop at generator output 5. Trigger pulses Beac the output of the trigger 4 through the delaying element 8 of the delay with the delay time tj, the pulse duration and 2, from the generator 2., arrive at the first input of the element 9 AND (Uj,). The pulses Ui of the generator 2, arriving at the second input of element 9I during the presence of pulses U at the first input of element 9I, pass through it and enter the input of key 7. The key 7 opens and the voltage is transferred from the charging capacitor 6 to the output of the pulse phase detector. The pulses Ur from the output of the phase-pulse splitter 3, arriving at the input of the generator 5, discharge the capacitor 6, which corresponds to the vertical line on the trapezoidal characteristic of the detector. After that, during time C, until the next pulse Uj arrives from the output of the phase-impulse splitter 3, the voltage on the capacitor 6 changes in the same direction as in the working section of characteristic t ;. , but with a much smaller slope. The voltage change on the capacitor 6 is caused by the leakage currents of the generator 5. In the considered mode of operation, the phase difference of the compared pulse sequences of the generators 1 and 2 to the voltage is converted in proportion to the slope of the working section of the device characteristics, II. The pulses from generator 2 lag behind the pulses from the first stroke (Urj.), But are ahead of the pulses from the other output (Ui) of the splitter 3 (1G, Fig. 2). In this case, the pulses. The incoming signals to the trigger 4 transfer it to the state when the trigger pulses of the IC begin to arrive at the generator 5 input from the trigger 4 output. . On the capacitor 6, the voltage Ug begins to change with a given slope, which corresponds to the working section t of the trapezoidal characteristic of the pulse-phase detector. The pulses UQ from the output of the splitter 3, arriving at the input of the trigger 4, transfer it to the initial state, the triggering pulses at the input of the generator 5 end, resulting in the charge of the capacitor 6. At the same time, the pulses Un enter the input of the generator 5 and produce In the course of time, as in the above-described mode of operation, the voltage on the capacitor 6 changes with a much smaller slope. Triggering pulses CD from the output of trigger 4 through delay element 8 with a delay time equal to the pulse duration (J from generator 2, are fed to the first input of element 9I (U). Pulses Uj from generator 2 entering the second input of the element during no pulses Ujj at the input of element 9I does not pass through it. The key remains closed and the voltage is not transferred from capacitor 6 to the output of the pulsed detector.

Thus, in this pulse-phase detector, the phase difference of the compared pulse sequences is converted into voltage only at the working section of the trapezoidal characteristic of the detector, i.e., the output voltage is unambiguously generated.

The use of this impulse detector in the auto-tuning system eliminates false hooks in which the short-term frequency deviations of the tunable generator are not compensated by the auto-tuning system, and provides the spectral frequency of the output oscillation of the auto-adapt system, which is especially important when building, for example , digital frequency synthesizers.

Claims (2)

1. USSR author's certificate Ml 508896, cl. H 03 D 3/02, 1974. 2. Authors certificate of the USSR W 275170, cl. H 03 K 9/04, 1968.