SU1566379A1 - Function generator - Google Patents

Abstract

The invention relates to a pulsed and computing technique and can be used to synthesize oscillations of complex shape, modeling processes in devices that require the conversion of digital signals into analog ones. The aim of the invention is to improve the accuracy of the generator. The functional generator contains a smoothing pulse generator 1, multiplying the D / A converter / UCAP / 2, the first element of the sample-storage 3, the output 4, the adder 5, the key 6, the second element of the sample-storage 7 and the inverter 8. Achieving the goal is achieved by introducing into the device a key 6, a second storage element 7, and an inverter 8, as well as a new connection between the constituent elements of the generator. 2 Il.

Description

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The invention relates to a pulsed and computing technique and can be used to synthesize oscillations of complex shape, modeling processes in devices that require the conversion of digital signals into analog ones.

The aim of the invention is to improve the accuracy of the generator.

Figure 1 shows a structural electrical circuit of a functional generator; figure 2 - timing charts of the signals at the outputs of the main blocks of the generator.

The functional generator (Fig. 1) contains a smoothing pulse generator 1, multiplying a digital-to-analog converter (UTAC) 2, first sampling-storage element 3, output 4, adder 5, switch 6, second sampling-storage element 7, and inverter 8, connected as shown scheme.

Functional generator operates as follows.

The generator 1 generates at its main output a source sequence of desired shape and frequency (Fig. 2a), which is fed to the analog input of UCAP 2. The latter performs scaling and polarity change of pulses in accordance with the difference code of adjacent nodal values of the restored signal (FIG. .2c) supplied by the data bus from POST (not indicated) to the digital input of UCAP 2, the time scale (duration of cycles) is determined by the pulse period from the main output of the generator 1.

When the first pulse arrives from the main output of the generator 1 to the input of UTsP 2, the latter generates the first smoothing pulse. In this case, a single signal from the output of the inverter 8 sets the key 6 to the Open state, the Formed smoothing pulse from the output of UCAP 2 through the key 6 is fed to the second input of the adder 5. The first input of the adder 5 contains a signal from the first sample-storage element 3 in the first current clock cycle is zero. From the output of the adder 5, the signal linearly increasing from zero at the beginning of the stroke to a value equal to the difference between the values of the second and first ordinates of the signal being restored (the value of the first ordinate of the signal is taken as

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zero), through the second element of the storage sample arrives at the output 4 of the generator. The second sample-storage element 7, operating in the Sampling mode, repeats the output signal at the output.

At the moment of reaching the maximum value of the first pulse of the initial sequence of the generator 1, a sync pulse is generated at its second output (Fig. 26), the duration of which is determined by the length of the falling edge of the pulse of the initial sequence of the generator 1, produces a sync pulse at its second output (Fig. 2b), the duration of which is determined is the duration of the trailing edge of the source sequence. This pulse arrives at the input of the inverter 8 and the control input of the first element 3 of the storage sample, by which the latter is set to the Sample state, and the inverter 8 goes to the state O. The key 6 goes to the Closed state and the second the sample-hold element is in the storage state. When the switch 6 is turned off at the output of the adder 5, the signal level is maintained by discharging a capacitor (not specified) connected to the second input of the adder 5 for the time required to switch the second sample-storage element 7 to the Storage state. The maximum value of the output signal stored in the second sample-storage element 7 goes to generator output 4 and through the first sample-storage element 3 (operating in the sample mode and repeating the input signal at the output); and the first input of the accumulator 5. On the second the input of the adder 5, the signal is zero for a time equal to the duration of the synchronization pulse.

At the end of the synchronization pulse and after the second pulse of the initial sequence from the first output of the generator 1, the inverter 8 goes to state 1, sets

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the key 6 is in the Open state, and the second element 7 of the sample-storage is in the Sample state. The first sample-storage element 3 enters the Storage state. In this case, the first input of the adder 5 contains the maximum value of the output signal of the previous clock cycle. Formed

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Claims (1)

Claims 20 Functional generator containing a smoothing pulse generator, the information output of which is connected to the analog input of a multiplying digital-to-analog converter connected by a digital input to the control input of the generator, the first sample-storage element, the information input of which is connected to the output of the generator and the output is connected to the first the adder input, characterized in that, in order to improve accuracy, a key, a second sample-storage element and an inverter that is included between you the course of the synchronization pulses of the smoothing pulse generator and the control input of the second sampling-storage element connected to the output of the adder and the output of the generator respectively, the output of the multiplying digital-to-analog converter is connected through a key to the second input of the adder, the control input is key with the inverter output, the control input the first element of the sample-storage is connected to the output of the synchronization pulses25 of the smoothing pulse generator. FIG. 2