SU1716573A1 - Device for protecting memory-stored data at power fail - Google Patents

Abstract

The invention relates to computing and can be used to create storage devices (mass storage) with the preservation of information when power is turned off. The purpose of the invention is to increase the reliability of the device. The device contains the main power source, the first and second blocking signal drivers, AND element, unlock signal generator, switch, switch, latch current limiter, backup power source, non-linear element. The goal is achieved by eliminating the thyristor effect of the accumulator on the K-MOS structures and eliminating its overheating. 3 ill., 1 tab.

Description

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The invention relates to computing and can be used in the manufacture of storage devices with preservation of information when power is turned off.

A device is known for protecting information in memory blocks when power is turned off, which contains a backup power source, one of the outputs of which is connected to a switch and the second to a non-linear element whose output is connected to the first driver of the output signals and the input of an external power source that is connected with the first and second triggers and the first and second elements OR - NOT. In addition, the device includes a second blocking signal driver connected to the switch and the first element OR NOT. The control inputs of the device are connected to the second inputs of the first and second elements OR - NOT, respectively / The outputs of the elements OR - are NOT connected to the second inputs of the first and second triggers, respectively. The output of the second trigger is connected to the driver of the input signals.

The drawbacks of the device are a decrease in the voltage of the backup power source, which causes a proportional decrease in the noise immunity of the device nodes, and low reliability in the operation mode in case of accidents in the power supply circuit, when false signals flow in the circuits.

The closest to the technical essence of the present invention is a device for protecting information in memory blocks when power is turned off, containing block signal shapers

sl VI

ABOUT)

unlocking, a switch, a drive on K-MOS structures, a main and backup power sources, a switch and a non-linear element whose input is connected to the output of the backup power source. The outputs of the main power supply and the blocking signal generator are connected to the corresponding inputs of the switch, the output of which is connected to the device power bus. The informational inputs / outputs of the accumulator are the informational inputs / outputs of the device, the address inputs, the chip select input and the record of the accumulator connected to the switch outputs respectively. The switch input is connected to the output of the unlock signal generator, the input of which is connected to the output of the blocking signal generator. The voltage outputs of the accumulator, the unlocking signal generator and the output of the nonlinear element are connected to the device power bus.

A disadvantage of this device is the possibility of a thyristor effect in the drive on the K-MOS structures, as a result of which the whole device fails, i.e. reliability is reduced.

The purpose of the invention is to increase the reliability of the device.

The goal is achieved by the fact that a latch current limiter, a second blocking signal generator and an And element, the first and second inputs of which are connected to the outputs of the first and second blocking signals, and the output to the first input of the blocking device are stored in the memory with information preservation. an unlock signal, the second input of which is the input of the device, and the output is combined with the input of the switch and with the first input of the switch, the second input of which is connected to the input of the second the driver of the blocking signal and with the output of the latch current limiter, the input of which is connected to the output of the main power source and the input of the first driver of the blocking signal.

It is known that the occurrence of the thyristor effect in the drive on K-MOS structures leads to thermal destruction of the LSI memory device, and can also lead to failure of the device elements connected in series with the drive. Therefore, in order to increase the reliability of operation, elements are introduced into the device that eliminate this effect.

FIG. 1 shows a storage device with preservation of information at

power failure; figure 2 - timing charts of the device; FIG. 3 shows an example of implementation of an unlock signal generator.

The device (Figure 1) contains the main

power supply 1, first 2 and second 3 blocking signal formers, element VI 4, unlocking signal generator 5, drive 6, switch 7, switch 8, latch current limiter 9, which is a series circuit LR, backup source 10 power, non-linear element 11.

Unlock Signal Driver

5 (fig.Z) contains the waiting multivibrator 12, the elements NOT 13 and 14, the trigger 15.

The device works as follows.

When you turn on the main source 1

0 power at the outputs of the first 2 and second 3 blocking signal drivers are set to high level signals (figure 2), which are fed to the inputs of the AND 4 element, from the output of which the high level signal is fed to the input of the unforming signal shaper 5. When accessing the drive 6 at the second input of the imaging unit 5, a low level signal is set, on the front of which

0 A resolution signal is generated for the switch 7 and the switch 8. In this case, the drive 6 is connected to the main power source 1 through a switch 7 circuit - latch 5 current limiter 9 the main power source 1, and the drive control address inputs and control inputs to the corresponding device inputs through the switch 8. At the simultaneous arrival at the input of the unlock driver, signals from the output of the AND 4 element and the request for the storage device, the output signal is generated with a time delay.

With a decrease in voltage in the power supply circuit of the storage device due to the disconnection of the main

5 A low level signal appears at the outputs of the shapers 2 and 3 of the blocking signal in the power supply source or the occurrence of the latch current in the accumulator 6 (see table). The low level signal at the output of the And 4 element causes an instantaneous change at the output of the shaper 5 of the unlock signal (Fig. 2), which removes the enable signal from the inputs of the switch 7 and the switch 8, as a result of which the drive

5 6 switches to the information storage mode with power from the backup power source 10 through the non-linear element 11.

Thus, in the proposed device, the LSI memory storage device for K-MOS structures is guaranteed

from failure due to overheating by a large latch current.

Claims (1)

Claims An information security device in memory blocks during a power failure, comprising a first blocking signal conditioner, an unlocking signal conditioner, a main and backup power sources, a switch, a non-linear element, a switch and a drive, while the output of the main power source is connected to the input the first shaper of the blocking signal, the output of the switch is connected to the output of the nonlinear element, the power inputs of the shaper of the unlock signal and the accumulator, the input of the nonlinear element coagulant connected to output backup power source, address and control inputs of the accumulator are connected to the switch outputs, data inputs of which are addressable and upPrimechanie. B - high signal level, H - low level signal. 2 # x, request memory Address memory housings write / read equaling inputs of the device, which is so that, in order to increase the reliability of the device, a latch current limiter, a second blocking signal generator and an And element are introduced into it, the first and second inputs of which are connected to the outputs respectively, the first and second blockers, the output element And is connected to the first input of the unlocking signal generator, the second input of which is the device request input, the output of the unlocking signal generator is connected to the control input of the switch Pa and with the control input of the switch, the signal input of which is connected to the input of the second blocking signal generator and with the output of the latching current limiter, the input of which is connected to the output of the main power source and the input of the first blocking signal generator. 7 P W eight V “- Shea.1 Voltage of the main source of litany The output of the first former is “blocking” Output of the second shaper ctiz AOwpofat / Circuit Output / V Memory request f t Exit Shaper Unlock tmt / p - Moment Occurrence / latch 8 mako / shtam on KMQL structures 2 i Have t