SU815864A1 - Method of cyclic amplyfying of slowly varying signals - Google Patents

Description

The invention relates to the amplification of weak constant and slowly varying electrical signals and can be used in precision normalizing amplifiers of direct current and multichannel automatic measuring systems of high sensitivity, containing high-speed digital measuring instruments. There is a known method of cyclic amplification of medium-varying signals, which includes fixing the input signal in the preceding cycle. The resulting signal is obtained in the next cycle, again reinforcing the fixed value of jLl. A disadvantage of the known amplification method is the large error of the resultant signal. The purpose of the invention is to increase the accuracy of gain. The goal is achieved by the fact that in the method of cyclic amplification of the variable signals, which, in the previous cycle, switched on fixation of the amplified input signal, in the subsequent cycle, the signal fixed in the first cycle is subtracted, the result of the subtraction is amplified K times, summed with the signal recorded in the first cycle and filtered. FIG. Figure 1 shows a block diagram of a cyclic amplifier of slowly varying signals, implementing the proposed method; in fig. 2a and b are diagrams illustrating sequential conversion of the input hopping signal; in fig. Pros and b are the static characteristic of the measuring amplifier and the resulting static characteristic of the cyclic amplifier. The cyclic amplifier contains a measuring amplifier 1, consisting of an input adder 2, an amplifier 3, an output adder. 4 and negative feedback circuits 5, and also remember3-8

The devices 6 and 7 with switches 8, and 9.

Works cyclic amplifier as follows.

In the first cycle of operation at the time point b (fig. 2a), the input signal HZSAL i (t) to be amplified is fed to the input of measuring amplifier 1, amplified, and the gain result (fig. 26) is fed through switch 9 to memory 7. In the following the amplification cycle, the memory 7 is disconnected from the output of the measuring amplifier 1 and connected by switch 8 to the adder 4. The signal fixed in the first cycle is attenuated K times by the negative feedback circuit 5 and fed to the input adder 2, where it is subtracted from the input wow signal. The result of the subtraction is amplified K times by amplifier 1 and, summing up B output adder 4 with the value recorded in memory device 7, forms at time 2 (FIG. 26) the resulting signal T, which after filtering, for example, a pulse filter, is fed on the measuring device. At the same time, the signal 3 is fixed by the memory 6 for use in the following cycles. Switches 8 and 9 are controlled both by periodic pulses from a special generator and by synchronizing pulses from a control circuit of a measuring system, of which this cyclic amplifier serves

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A comparison of the static characteristics T i (x) of the measuring amplifier 1 (Fig. 3a) and the cyclic amplifier (Fig. 36) shows that the error L of the measuring amplifier is eliminated when implementing this method of cyclic amplification.

The use of the method of cyclic amplification of slowly varying signals provides an increase in the accuracy of information-measuring systems (IMS), allows them to be constructed using an aggregation method and significantly reduces the number of standardized signals.

measures of digital devices and normalizing converters.

Claims (1)

1. Belenky, B.I. and Mints, M.B., Highly Sensitive DC Amplifiers with Converters. L., Energie, 197O, p. 331. figure 1 a X ii i I I iot / 2 Fmg7 Fig.Z