SU1487191A1 - Multichannel code-voltage converter - Google Patents

Description

The invention relates to automation and computing and can be used in multichannel converters of digital information into analog. The purpose of the invention is to improve the accuracy and simplification of the Converter. The multichannel code-voltage converter contains 1 interface bus, an on-line backup device 2, a block of 3 analog switches, a generator of 4 pulses, a driver of 5 address signals, made in the form of a pulse counter, a controlled source 6 of the reference voltage. The controlled voltage source 6 is made on an analog storage device—

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not 7, the key 8, the source 9 voltage unit 10 discharge, made in the form of a parallel connected resistor 11 and a capacitor 12. Putting the digital codes of all converted values in the operational memory

"device 2 with the subsequent reading from it at the same time information about the same-named discharges of all convertible channels ensures the achievement of a positive effect. 1 Cp f-crystals, 1 ill.

The invention relates to automation and computing and can be used in multichannel converters of digital information into analog.

The purpose of the invention is to improve the accuracy and simplify the converter.

The drawing shows a functional diagram of a multichannel code-voltage converter.

The code-voltage multichannel converter contains a bus 1 interface, a random access memory 2, a block of 3 analog switches, a ^ 5 generator of 4 pulses, a driver of 5 address signals made in the form of a pulse counter, a controlled voltage source 6. The controlled source 6 of the reference voltage is made on an analog storage device 7, a key 8, a voltage source 9 and a discharge unit 10 made in the form of a parallel-connected resistor 11 and a capacitor 34 12. ·.

The code-voltage multichannel converter works as follows.

From the information outputs of the bus 1d (interface to the random access memory 2 (if there is a "Record" command) to "certain addresses arriving at the first address inputs A,.,. And _{P of the} operative storage device RAM 2 from the bus 1 of the interface , the information is sequentially recorded in ¹ as digital codes of all converted variables.After the recording is completed, the "Read" command is sent to the corresponding input of RAM 2 from the output of bus 1 of the interface, and then the "Start" command is received. source 6 -opo Directly at - $ voltage, the capacitor 12 of which begins to discharge through the resistor 11 exponentially.The discharge rate of the capacitor 12 is determined by the block time constant.

10 bits and equal to = K < _g C _n . At the same time, the Start command starts a generator of 4 pulses and at the output of the pulse counter 5, the address code of the digits Β _ν , .Β _{η is} generated, which ensures that information is read from RAM 2 bitwise e, "bit 'slices" simultaneously across all convertible channels. Synchronously with the process of bit-by-bit information reading from RAM 2, the analog information (voltage) from the output of the analog storage device 7 of the controlled voltage source 6 is also read out. At the same time, the voltage value at the output of the controlled source 6 varies according to the degrees of the base of the number system used in the specific performance of the multi-channel code-voltage converter. The specified synchronism is provided by the mutual choice of the value of the time constant and frequency of the generator 4 pulses.

The inclusion of the bit analog key of the block 3 analog keys is carried out only by significant values of bits of the converted codes. As a result, at the output of each channel of a multichannel converter, a voltage code forms an analog signal, the volt-second area of which is proportional to the corresponding value of the converted code of this channel recorded in RAM 2.

At the end of the conversion, the “End of conversion” signal is generated at the second output of the shaper of 5 address signals and is sent to the corresponding input of bus 1 of the interface, as a result of which the “Start” command is removed, the key 8 of the controlled source 6 closes and connects the output of the voltage source 9 to block 10 discharge, providing a charge con5

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densator 12 to the original value.

At this the conversion cycle ends, and when the "Record" command arrives, the next conversion cycle begins.

It is advisable to use a multi-channel code-voltage converter in complex measuring and control systems with a large number of channels. At the same time, compared to the prototype, this converter has significantly lower equipment costs per channel, information channel of the common bus-1 type, is minimally loaded, increasing the number of channels does not entail loss of accuracy and does not affect the duration of the conversion cycle.

Claims (2)

Claim 1. A multichannel code-voltage converter containing η analog keys, an interface bus, an address signal maker and a random access memory, whose information inputs are connected to the corresponding information bus outputs of the interface, characterized in that, in order to improve accuracy and simplification, A controlled voltage source and a pulse generator are entered into it, and the address signal shaper is made in the form of a pulse counter, the counting input of which is combined with the first control input the reference voltage source and connected to the output of the pulse generator, the start input of which is combined with the second input of the controlled reference voltage source and connected to the start output of the interface bus, the channel address outputs of which are connected to the corresponding first address inputs of the RAM, the second address inputs the inputs of which are connected to the corresponding information outputs of the counter 0 pulses, the transfer output of which is connected to the "Conversion end" input of the interface bus, the "Write and read" outputs of which are connected to the operational inputs of the same name ₅ memory devices, the outputs of which are connected to the control inputs of the corresponding η keys, the outputs of which are the output bus, the output of the controlled source θ of the reference voltage is connected to the information inputs η of the keys. 2. The code-voltage converter according to claim 1, characterized in that the controlled source of a reference> 5th voltage is made on a voltage source, an analog storage device, a key and a discharge element ·, made in the form of a parallel-connected resistor and capacitor, u the first output of the last of which is a zero potential bus, and the second output is connected to the output of the key and the information input of the analog storage device, the control input and output of which '5 are respectively the first input and output of a controlled voltage source, the voltage source output is connected to a key information input, the control input of which is • 0 pogo is the input of a controlled voltage source.