SU734728A1 - Digital-analogue function generator - Google Patents

Description

The invention relates to automation and computing, in particular, to devices for converting a digital code into a voltage. A known functional prefix tep code-voltage contains an input register, a decoder, two code-voltage converters, four groups of reference conductivities with keys, and operational amplifiers .JQ. The drawbacks of the device are the complexity of the constructive implementation in reproducing a wide class of functions and low technology, determined by the need to use a large number of reference conductivities of various values. A code-voltage functional converter is also known, which contains the digital-to-analog transducers of the delay element transducers, the digital-to-analog block and the memory block of nodal ordinates and derivatives in nodes 2 device drawbacks — the complexity of the device implementation for reproducing a wide class of functions and a large block size memory The closest to the invention is a digital-analog. Functional converter containing a first register connected by a digital input to an input bus of a device and a connecting direct output to an input of a block of adressacEN connected by outputs to two inputs of an OR block, the first output of which is connected to a digital input of a second the register connected by the control output to the control input of the switch of the reference voltage, the output of which is connected to the analog input of the first linear linear circuit A converter connected by the output to the input of the first large-scale amplifier, and the output of the second OR block are connected to a digital input of the third register connected to the digital input g of the second Bi-linear converter, the analog inputs of which are connected to the reference voltage buses, and the output through the reference resistor is connected to the first input of a summing amplifier connected by an output to the output bus of the device and connected by a second input to the output of the third digital-to-analog linear cable An emitter whose digital & input is connected to the second output of the second register, and an analog input is connected to the output of the first large-scale amplifier, and the digital input of the first digital-analog linear converter is connected to the first output of the first register I. The disadvantage of the device is the complexity of the realization when playing complex class of Fujudi with high accuracy, definable, in particular by a significant complication of a logic block and an increase in the number of its connections with other blocks with increasing the number of subintervals of functions. The purpose of the invention is to simplify the device while expanding the class of reproducible functions and improving accuracy. The goal is achieved by the fact that a digital-to-analog functional converter contains a first register connected by a digital input to the input bus of the device and connected by a direct output to the input of the addressing unit connected by codes to the inputs of two blocks of OR elements, the output of the first one being connected to the digital input the second register connected to the control output is familiar to the control K4ty input of the switch of the reference voltage, the output of which is connected to the analog input of the first digital-to-analog linear the converter connected to the input of the first ma: m tabular amplifier, and the output of the second unit OR connected to the digital input of the third register connected to the digital input of the second digital analogue converter of the second digital analog converter with tires of the reference voltage , and the output through the reference resistor is connected to the first input of the summing amplification, connected by the south output with the output bus of the device and connected by the second input to the output of the third digital-arc linear transducer The aerotovat, whose digital input is connected to the digital code of the second register, additionally introduced two code transmission units, a second large-scale amplifier and a fourth digital-to-analog linear converter connected by an analog input to the output of the first scaling amplifier, a digital input to the output of the first code transmission unit, and an output - to the input of the second large-scale amplifier connected with the output to the analog input of the third digital-to-analogue linear converter, and both code transmission units are connected respectively tven- but nepBbnvoi inputs with straight pervsmgche output register, the second input - to pervogs inverted output) registers, and third inputs to the outputs of the addressing unit and output a second code transmission unit connected to the digital input of the first digital to analogue linear transducer. The drawing shows a block diagram of the device. The digital-to-analog functional converter contains the first register 1 with direct output 2 and inverse output 3, the first and second blocks 4 and 5 of the transmission of the code. The addressing block 6 is the first, second, third and fourth digital-analog linear converters 7-10, the first and second mashgbnye The amplifiers 11 and 12, the summing amplifier 13, the first and second blocks of elements 14 and 15 AND LI, the second and third registers 16 and 17, the reference resistor 18 and the switch 19 of the reference voltage. All converters 7-10 are designed as R-2R controlled resistors. The device works as follows. The code N j to be functionally digital-analog converted on the input bus of the device is written to the register 1, From the direct output 2 of register 1, the MX code acts on the addressing block 6. The number of output tires of block 6 is equal to the number of approximation sections. Each current value of N y in block 6 corresponds to the excited state of one of the output buses of this block. This excitation signal, acting on the blocks of elements 14 and 15 AND LI, records the corresponding control codes in registers 16 and 17, and also provides feed to the converters 7 and 1O through the blocks

5 and 4 of the lbbo direct value of the code or the inverse value of H of this code.

Depending on what value (direct or inverse) of the code H) (arrives at the inputs of converters 7 and 10, the type of function reproduced in the jth approximation segment changes

Thus, the canopy that the output impedance of each array of converters 7-1O is equal to R, the nominal values of the resistors in the feedback circuits of the amplifiers I-13 are respectively, (1 f Tnj, R and, and the nominal value of the reference resistor 18 is equal to (t - 1) R, the output voltage of the device and 2, taken from the output of the amplifier 13 in the j -th approximation area is equal to;

a) for the case when the converters 7-1O are controlled by the code H, taken from the direct output of the register 1. VVV | o, l gp -V e DO is the reference voltage; N. IM. - control codes in the register 16 and 17j Р - the size of the code N without a sign bit; - code width without considering the sign bit, - N code width in register 1; b) for the case when converter 7 and 10 are controlled by an inverse code, (Number where Nt x) for the case when converter 7 is controlled by a direct code H, and converter Yu is controlled by an inverse code. 7 VKax-.V The programming of the device is in the selection at each site.

approximation of one of the above modeling dependencies, as well as writing in the register of N code and its sign and N g code with its sign, the programming technique consists in connecting the input buses of blocks 14, 15 and third inputs of blocks 4 and 5 with the corresponding output buses of block 6.

Claims (2)

Introduction to the structure of the device additional two code transmission units. a large-scale amplifier and a digital-analog linear converter allows, in comparison with the known device, to simplify the constructive implementation of the 1-phase analog-functional converter when expanding the class of reproducible functions and improving accuracy, which is ensured, in particular, by using a smaller number of approximation segments. DETAILED DESCRIPTION OF THE INVENTION A digital-analog functional converter containing a first register connected by a digital input to an input bus of a device and connected directly to an input of an addressing unit connected to video inputs to the inputs of two blocks of OR elements, the output of the first of which is connected to a digital input of the second register connected by a control output to the control input of a reference voltage switch, the output of which is connected (1nen to the analog input of the first digital-to-analog linear converter, The output is connected to the input of the first large-scale amplifier, and the output of the second block of elements OR is connected to a digital input of the third register connected to the digital input of the second digital-to-analog linear converter, the analog inputs of which are connected to the reference voltage buses and the output through the reference resistor is connected to the first input summing amplifier connected to the output bus of the device and connected by a second input to the output of the third digital-to-analog linear converter, digital the left input of which is connected to the digital output of the second register, characterized in that, in order to simplify the device while expanding the class of reproducible functions In addition, two code transmission units, a second large-scale amplifier and a fourth digital-to-analog linear converter connected by an analog input to the output of the first scale amplifier, and a digital input to the output of the first block of code transmission, and an output to the input of the second large-scale amplifier were added to the digital-to-analog functional converter. connected with the analogue BXCV of the third digital-to-analog linear converter, with both code transmission units connected together with bubbled inputs to direct output of the first register, the second input with an inverted BbKoaoM first register, and the third input - to the outputs of the addressing unit, and the output of the second block of code per country houses connected to the digital input of the first digital to analog converter lineynsygo. The source of information ,. prichggye into account during the examination 1. USSR Copyright Certificate № 367543, cl. a About q 7/26, 1971. 2. Authors sketches of the USSR No. 432546, cl. Q 06 T S / OO.- 1872. 3, USSR inventor's certificate 572815, cd. G06 J 1/00, 1976 (prototyp) m, ft .V.JY mgK