SU1485310A1 - Analog memory - Google Patents

Description

The invention relates to the field of computing, in particular to a storage device (memory), and can be used in analog-to-digital converters as an analog storage device for the implementation of discretization of electrical signals. The purpose of the invention is to improve the accuracy is achieved by the introduction in the mouth2

The operation of the operational amplifier, the third and fourth current generators, voltage divider and current supply elements. In the sampling mode, the currents of the generators 5 and 6 flow through key 1, unlocking it. Capacitor 2 charges to the value of the input signal and tracks it. The tracking accuracy depends on the relative accuracy of the currents specified by the first 5 and second 6 current generators. There is a decrease in the static error of the device, a change in the potential at the output of the operational amplifier 12 causes a decrease in the current of the generator having a higher current value, and an increase in the current of the generator having a lower current value. Thus, a negative feedback acts to ensure exact coincidence of the values of the currents of the generators 5 and 6. 1 Il.

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The invention relates to computing, and in particular to storage devices, and can be used in analog-to-digital converters as an analog storage device for implementing the sampling of electrical signals.

The aim of the invention is to improve the accuracy of the device.

The drawing shows the function. The circuit diagram of the proposed device.

The device contains a bridge diode switch 1, a cumulative element on a capacitor 2, an output amplifier 3, a switch 4, current generators 5 8, a voltage divider 9 on resistors 10 and 11, an operational amplifier 12, current-generating elements 13 and 14, a bus 15 of zero potential of the device, power inputs 16 and 17, information input 18 and output 19. The first current-carrying element 13 is made on a resistor 20 and transistor 21, the second current-giving element 14 is on a resistor 23 and transistor 24. The current generators 5 and 7 and the current generators 6 and 8 on transistors of different wire properties.

The device works as follows.

The discretized signal is fed to the signal input of the bridge diode key 1. In the sampling mode, the currents of the current generators 5 and 6 through the switch 4 flow through the key 1, unlocking it. Capacitor 2 charges to the value of the input signal and tracks it. The tracking accuracy depends on the relative accuracy of the currents given by the first 5 and second 6 current generators. Suppose that the values of the currents of the first 5 and second 6 current generators are not. match up. In the same way, the currents of the third 7 and fourth 8 current generators will differ. The difference between the currents of the first 5 and third 7 current generators, as well as the second b and fourth 8 current generators is ensured by the same potential of their bases and the homogeneity of the parameters of transistors of the same conductivity type. In the case of integrated manufacturing technology of the device, this condition is provided by the technology, in the case of the implementation of the device on discrete elements

can be used differential pairs of transistors manufactured by integrated technology. The potential of the connection point of the third 6 and fourth 8 current generators will be shifted relative to the midpoint determined by the voltage divider 9 towards the voltage source supplying the current generator with a large current value. This shift is transmitted by the operational amplifier 11 to the connection point of the current supply elements 13 and 14, defining current mode current generators on the principle of a current reflector. The change in potential at the output of the operational amplifier 11 causes a decrease in the current of the generator, which has a higher current value and an increase in the current of the generator, which has a lower current value. Thus, negative feedback acts to ensure the exact coincidence of the values of the currents of the first 5 and second 6 generators, - As a result, the static error of the device in the tracking mode decreases. When switching to storage mode, switch 4 disconnects the control currents from key 1 using any of the methods used.

Claims (1)

Claim An analog storage device containing a storage element on a capacitor, one of the plates of which is connected to the zero potential bus of the device, the output amplifier, whose output is the output of the device, a bridge diode switch, the output of which is connected to another plate of the capacitor, and the information input of the output amplifier, switch, the outputs of which are connected to the control inputs of the bridge diode key, the information input of the bridge diode key is the information input of the device, the first and The second is the current generators, the outputs of which are connected to the information inputs of the switch, characterized in that, in order to improve the accuracy of the device, an operational amplifier, a third and fourth current generators, a voltage divider and current supply elements, the first outputs of which are connected to the output of the operational amplifier, are introduced into it, control inputs of the first current generator, 1485310 The first current supply element and the third current generator are connected to the second output of the first current supply element, the control inputs of the second current generator, the second current supply element and the fourth current generator are connected to the second output of the second current supply element, the first input of the voltage divider is the first power supply input of the device and is connected to the power inputs the first current generator, the first current-emitting element and the third current generator, the output of which is connected to the non-inverting input of the operating force ator and output a fourth current generator, the input power of which is the second input device and the power supply is connected to the inputs of the second current generator vtoro10 th voltage driving member and with a second input of the voltage divider whose output is connected to the inverting input of the operational amplifier. Companion A.Voronin