SU1695506A1 - Device for smoothing of signal of digital-to-analog computer - Google Patents

Abstract

The invention relates to automation and computing and can be used in systems converting digital information into analog. The purpose of the invention is to increase information reliability by simplifying the device. The device for smoothing the digital-to-analog converter contains a digital-to-analog converter 1, O-flip-flop2, an integration block 3, the first 4 and second 5 keys, the first 6 and second 7 of the sampling and storage device, the Integration block 3 is designed as an operational amplifier 8, the first 9 and second 10 resistors and capacitor 11. The positive effect is achieved by introducing negative feedback from the output to the input of the interpolator. 1 il. WITH S

Description

The invention relates to automation and computer technology and can be used in systems for converting digital information to analog.

The purpose of the invention is to increase information reliability by simplifying the device.

The drawing shows a device, a functional diagram. ;

The device for smoothing the signal of the digital-to-analog converter contains a digital-to-analog converter 1, D trigger 2, an integration unit 3, first 4 and second 5 keys, first 6 and second 7 sampling and storage devices. The integration unit 3 is made bi in the form of an operational amplifier 8, the first 9 and second 10 resistors and a capacitor 11.

The device for smoothing the signal of the digital-to-analog converter operates as follows.

At the moment of arrival of the synchronization pulse (this pulse arrives simultaneously with changing the value of the converted code), the new code value is written to the digital-analog converter 1, and D trigger 2 changes its state (for example, a Log. 0 ”level is formed at its direct output). In this case, the first sampling and storage device 6 is transferred to the information storage mode, the first key 4 is closed, the second key 5 is opened, and the second sampling and storage device 7 is transferred to the tracking mode of the output signal of the integration unit 3. The signal from the output of the digital-to-analog converter 1, corresponding to the new value of the converted code, is fed to the second input of the integration unit 3, the first input of which receives the signal corresponding to the previous value of the converted code. Thus, the integration unit 3 generates at its output and the output of the Eicero device as a whole a signal proportional to the voltage difference corresponding to the current and previous values of the converted code.

This difference signal is interpolated and a linearly varying voltage will be formed at the output of the device during the quantization interval At.

The time constant of the integration unit 3, made on the basis of the operational amplifier 8 with a capacitor 11 in the feedback circuit, is selected so that during the quantization interval At the voltage at its output linearly changes by a value proportional to the difference in input voltages. This time constant is provided by the appropriate choice of resistances of resistors 9 and 10.

The voltage from the output of block 3 through alternately working devices 6 and 7 of the selection and storage and electronic keys 4 and 5 is supplied to its second input.

Connecting the output signal of the operational amplifier 8 to its inverting input leads to the appearance of negative feedback acting with a delay by the quantization value At of the digital-to-analog converter.

Negative feedback compensates for errors caused by the leakage current of the integrating capacitance, eliminates the saturation of the integration unit, eliminates the need for discharging the integrating capacitance at the end of each quantization period, thereby improving the quality of the output signal of the signal-smoothing device of the digital-to-analog converter.

Claims (1)

Claim A digital-to-analog converter signal smoothing device, comprising a digital-to-analog converter, the information inputs and the synchronization input of which are respectively the input bus of the code to be converted and the input synchronization bus, a trigger whose inverse and direct outputs are connected to the control inputs of the first and second keys, respectively, the output of the latter is connected to the first input integration unit, the output of which is the output bus, the information inputs of the first and second keys are connected to the output of the first and second sampling and storage devices, respectively, characterized in that, in order to increase reliability by simplifying the device, the trigger is made in the form of a D-trigger, the synchronization input of which is combined with the synchronization input of the digital-to-analog converter, and the information input is connected to the inverse output of D -trigger, the output of the integration unit is connected to the information inputs of the first and second sampling and storage devices, the control inputs of which are combined with the control inputs of the first and torogo keys, the first key output combined with the output of the second switch, the output digital to analog converter coupled to the second input of the integrating unit.