SU598233A1 - Digital-analogue multiplier - Google Patents

Description

(54) DIGITAL AND ANALOG MOVIFIER

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The invention relates to a pulse technique. The multiplier is used to convert information, in particular, to multiply a signal in coded form by a signal in analog form with the result shown as voltage.

A digital-to-analog multiplier is known that contains a register with built-in gates and sign bit, an analog-to-digital converter, a resistive matrix, and analog switches. The disadvantage is its limited dinamic range of input signal.

Closest to the present invention is a digital-analog multiplier containing a register with a sign bit, an analog current-voltage converter with a differential input, an inverted resistive matrix, analogous to and around analog switches, the like outputs of which are interconnected and connected to the zero bus and through a two-way analog switch, the control input of which is connected to the sign bit, the JC inputs of the analog converter, a transistor group of two sources but-weighted currents through resistors 2R matrix which are connected to vhodamk porazr dnyh analog switches, and analog input device having a potential and current outputs respectively connected to the control input transistor group and the entry of the matrix 2.

- A disadvantage of the known device is the limited dynamic range of input signals in analog form, as a result of which two quadrants and the area of small input signals are excluded from the working area. The aim of the invention is to expand the dynamic range of the input voltage.

This is achieved by the fact that the digital-analog multiplier containing i is a register with a sign bit and with built-in forward and inverse code reading gates, whose bit outputs are connected to the corresponding

inputs of the first on-off analog switches, the outputs of which are combined with the outputs of the second on-off analog switch, with other inputs of the first on-off analog switches connected to the outputs of the inverted resistive matrix, the terminal resistor of which is connected to the signal input of the second on-off analog switch, and the analog current-to-voltage converter , matching resistors В. и 2В and a sign two-item analog switch were introduced. The control input of the latter is combined with the control input of the second down-analog analog switch and the output of the sign bit register, the signal input is connected via a matching resistor 2R to the multiplier input terminal connected to the inverted resistive matrix input, and the corresponding outputs of all two-position analog switches The sensors are connected to the inverting and non-inverting inputs of the analog current-voltage converter. The drawing shows a structural diagram of a digital-analog multiplier containing a register 1 with a sign bit 2 and embedded direct and inverse code reading gates, with the register bits arranged in order of magnitude from left to right, an analog current-to-voltage converter 3 with an inverting 4 and non-inverted 5 inputs, made, for example, on two operational amplifiers, an inverted resistive type Y matrix R-2-nd with a group of two equivalent analogue switches 7, sign two-way analog the first switch .8. The same outputs of the switches 7 are interconnected by parallel (a., And;; Nodkl10) to the inputs 4 and 5 aMalTptoSoro, n eo6 | zaz6vatel 3, control to} these inputs:; Reconnecting the wires are connected lk g; orae1 outputs 1 regenstr; a-1 ;,. and control input 9 of the switch $ is connected directly to the OUTPUT - significant digit of the 2nd register of this register. Input signal Search (analog multiplier) is connected to matrix 6 through a resistor 10 with resistance 8, and to the signal input II sign switch 8 through resistor 12 double resistance 2Ei. Termination resistor 2 The R matrix is connected to the signal input 13 of a two-way analog switch 14, the control input 15 of which is connected to the same input 9 of the switch 8. The outputs of the latter are cross-connected to the same output 1 by switches 7 and 14. All analog switches can be executed, for example , on field transistors, reed switches, optoelectronic keys, etc. The digital-analog multiplier works as follows. When selecting the resistance of resistors 10 and 12 in exact correspondence with the resistances of the matrix b, the input resistance across the analog input G is constant and equal to B, since the current inputs 4 and 5 of the converter 3 are potentially grounded (the inputs of the operational amplifiers). Thus, the input current is divided into two equal parts - | i of which the first flows through the resistor 12, and the second through the resistor 10 and the matrix b. When the values at the outputs Ij or Ijs 4, the serial switches respectively connect the current signals of the 2R branches to the inputs 5 and 4 of the converter 3, which corresponds to the assignment of these signals to an additional multiplier 11 or, 1 regardless of the current ig and its direction the presence of reading gates in register 1 and when the value of the sign bit is equal to zero, the value of bits corresponds to the significant bit of the digital accommodation number, and for the sign bit equal to one, its inverse value. at the inputs of the converter 3 current signals with a discreteness corresponding to the low-order quantum, the limiting values of which are J. rcs 0.0000 - iife - iife "Pt O.ilii-yifcj + Aijjj at 1.0000 P Elimination of the ambiguity of the characteristics of the converter in the region at the sign the bit zero is produced by subtracting from these magnitudes the current -, .... a - at the sign of the bit unit one - by adding the current, which is realized by a crossover, connecting the outputs of the switch -8: to the same one. amendments. 4 d «,, (at the sign of the discharge zero-D-xx at the sign of the discharge of the unit realized by the switch 14. The multiplier characteristic is in the form of a stepped broken line with limit values -t5.4-2dij, at 0. CPU + t§ -2dij, at i.au О at 0.0000 U 1.0000 The absolute value of the current quantum is equal to / where tf is register register 1, and the entire multiplier has, due to the effect of potential grounding of analog switches on inputs 5 and 4, by multiplying characteristics in all four quadrants, including in the field of small signals.

Claims (2)

1. Netrebenko K.A. Digital voltage dividers, M., Energie, 1970, p.114. 2. Moporn "eb TZ / A conve te Achieves. 0,05J irteafiiy wiih lO-Eii T esoEuliort, EEectroHic ,, v ..