KR100326245B1 - Apparatus for conversion to standby mode in a specified temperature - Google Patents

Abstract

PURPOSE: A device for switching into standby mode at specific temperature is provided to prevent stored data and an abnormal operation of a chip, by detecting whether a chip operates over an operating temperature and switching the chip into a standby mode. CONSTITUTION: A sense part(10) receives a burn-in signal(BURN_in) for a burn-in test operation and senses variation of a threshold voltage to a temperature. A control part(12) responds to a sense signal from the sense part(10) and the burn-in signal and generates a standby signal for switching a chip into a standby mode. A chip mode switching part(14) switches a memory chip into the standby mode in response to a standby signal from the control part and a chip select signal(/CS) or a snooze signal(ZZ).

Description

Apparatus for conversion to standby mode in a specified temperature}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device operating in response to temperature, and more particularly, to a device for sensing a high temperature above an operating temperature and switching a chip or device to a standby mode.

In general, when a chip operates out of an appropriate environment (especially a temperature) that guarantees normal operation specified in the specification of a memory chip, the chip life time is usually caused by a malfunction of the chip or an excessive operation of the chip. Problem occurs that decreases. In addition, when a chip malfunctions, data stored in the chip is erased by a malfunction, thereby preventing data from being maintained in normal operation.

Therefore, there is a need for a device that detects a chip operating at a high temperature outside of an appropriate environment and prevents chip malfunction and unreasonable operation.

The present invention has been proposed in accordance with the above requirements, and detects when the chip is operating at a high temperature exceeding the operating temperature to automatically switch the chip to the standby mode to protect the stored data, and prevent the chip malfunction The object is to provide a standby mode switching device at a specific temperature.

1 conceptually illustrates an apparatus for switching to a standby mode for a particular temperature of the present invention.

2 is an internal structure diagram of a sensing unit.

3 is an internal structural diagram of a control unit;

4 and 5 are simulation diagrams of the present invention.

* Explanation of symbols for the main parts of the drawings

10 detection unit 12 control unit

14 chip mode switching unit 20 voltage divider

22: Option part 24: Switching part

According to an aspect of the present invention for achieving the above object, the sensing means for generating a detection signal by detecting a change in the threshold voltage under a specific high temperature above the operating temperature of the chip operating; Control means for generating a standby signal for switching to a standby mode in response to the sensing signal and the burn-in signal output from the sensing means; And mode switching means for switching the chip to the standby mode by blocking a chip control signal for controlling the operation of the chip under the specific high temperature in response to the standby signal output from the control means. The sensing means includes a plurality of MOS Field Oxide Transistors, and senses that the absolute value of the threshold voltage of the transistor decreases as temperature increases, thereby detecting the sensing signal. It is characterized by generating.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The present invention is based on the fact that the threshold voltage (hereinafter referred to as Vth) of a MOS Field Oxide Transistor acts as a variable with temperature. In other words, the Vth of the MOS transistor uses the point that the absolute value decreases as the temperature increases.

FIG. 1 conceptually illustrates an apparatus for converting to a standby mode for a specific temperature in a memory chip according to an embodiment of the present invention, and receives a burn-in signal BURN_in # for a burn-in test, wherein the temperature A controller for sensing and switching a change in Vth with respect to the controller; and a controller configured to generate a standby signal for converting the chip into a standby mode in response to a sense signal and a burn-in signal BURN_in # output from the detector 10 ( 12) and a chip mode switching unit 14 for switching the memory chip to the standby mode in response to the standby signal and the chip select signal / CS or the snooze signal ZZ output from the controller 12.

2 is an internal structure of the sensing unit 10, in which 20 is a voltage divider, 22 is an option unit, and 24 is a switching unit, respectively.

In operation of the sensing unit 10 of the present invention, first, the PMO transistors connected in series to receive different control signals d, c, b and a from the option unit 22 to the gate for application under various power supply voltage environments. One of (P1, P2, P3, P4) is turned on to be connected to the voltage divider 20. The number of transistors for performing the voltage dividing operation of the voltage divider 20 is determined from the PMOS transistor turned on in the option unit 22.

The PMOS transistor of the voltage divider 20 has a difference of ΔVth between Vth at 0 ° C and Vth at 90 ° C, and the MOS transistor connected in series generates a difference (N × ΔVth) by a continuous sum of ΔVth. do. In the range of 0 ° C to 90 ° C, the ΔVth per MOS transistor is about 0.25V, and when connected in series with four stages, the difference is about 1V. That is, the output voltage A of the voltage divider 20 changes to 5ΔVth at ground as the temperature changes to a high temperature, and the inverter I1 of the switching unit 24 is switched by 5ΔVth. .

The switching unit 24 is designed to be switched by a difference between the ground power supply and the output voltage of the voltage divider 20, and outputs a detection signal PTS. The switching unit 24 is composed of inverters I1 and I2 connected in series.

For example, when the PMOS transistor P1 is selected and connected to the voltage divider 20 through the option unit 22 at a 5V power supply voltage and a temperature within a normal operation range, the connected PMO transistors P5, Due to the voltage drop of P6, P7, P8 and P9, the output voltage (node A) of the voltage divider 20 becomes the ground power supply level. Accordingly, the switching operation of the switching unit 24 does not occur, and the sensing signal PTS maintains the ground power level.

When the temperature gradually rises to 90 ° out of the normal operation range, a voltage drop is made through the PMOS transistors P5, P6, P7, P8, and P9 of the voltage divider 20. When the difference ΔVth is 0.25V, 1.25V causes a switching operation in the switching unit 24, and the sensing signal PTS is output at the power supply voltage level.

The NMOS transistor N1 of FIG. 2 is added to prevent a case in which the standby mode switching device of the present invention does not perform a burn-in test for a high temperature deliberately applied during the burn-in test, and the burn-in signal BURN_in # is When applied, the standby mode switching device of the present invention is disabled to enable burn-in test.

3 is an internal structure of the control unit 12 and generates a standby signal standby for converting the chip into the standby mode in response to the detection signal PTS and the burn-in signal BURN_in #, but inverted the detection signal PTS. And an inverter I3 which receives the burn-in signal BURN_in # as an input and inverts the output from the negative logic gate ND1 and the negative logic gate ND1. In response to the detection signal PTS of the power supply voltage level output from the sensing unit 10, a standby signal standby of the ground power supply level is output. Here, the input burn-in signal BURN_in # is also added to disable the standby mode switching device during the burn-in test to perform the burn-in test.

The standby signal of the grounding level is input to the chip mode switching unit 14 to block the chip select signal / CS and the snooze signal ZZ from being entered into the chip. To be switched to. Therefore, the previously stored data is kept as it is, it is possible to prevent malfunction and excessive operation of the chip.

On the other hand, the chip mode switching unit 14 will be described in more detail as follows.

The chip mode switching unit 14 receives a standby signal of ground level applied through the sensing unit 10 and the control unit 12 when the chip is at a high temperature outside the normal operating range, and receives the chip selection signal ( / CS) and the snooze signal ZZ as a means of blocking the input into the chip, the internal configuration can be simply implemented by logic gates by those skilled in the semiconductor chip design. For example, when the standby signal is a ground power level (low signal) by receiving the chip selection signal / CS and the standby signal, which are the low active signals, the high level regardless of the signal level of the chip selection signal / CS. A low level irrespective of the signal level of the snooze signal ZZ when the standby signal is a ground power supply level (low signal) by receiving a negative logic gate that outputs a signal, a snooze signal ZZ which is a high active signal, and a standby signal. It is configured to include an AND gate to output a signal, and the chip is automatically switched to the standby mode by disabling the chip select signal (/ CS) and the snooze signal (ZZ) applied to the chip by the standby signal of the ground power level. It can be done.

4 and 5 are simulation diagrams of the present invention, and FIG. 4 shows a ΔVth characteristic, and FIG. 5 shows a graph of a sensing signal PTS and a standby signal according to temperature change.

When the standard operating temperature is 0 ℃ ~ 70 ℃, the simulation is aimed at 90 ℃ based on 4.5V supply voltage. FIG. 4 shows the detection signal when the sum of ΔVth due to the change of Vth becomes 4.5V. It can be seen that PTS) is switched. FIG. 5 shows that the standby signal is toggled around 90 ° C. when the temperature is swept.

The standby mode switching device for the specific temperature of the present invention can be applied not only to memory chips but also to electric devices that can generate instantaneous high heat, fan controllers of automobiles, and the like.

The present invention as described above, by generating a standby signal by detecting a high temperature above the operating temperature to enable the switch to the standby mode of the chip, to protect the data stored in advance at high temperature, failure generation and life due to malfunction It is effective in preventing time reduction.

Claims (8)

Sensing means for detecting a change in a threshold voltage under a specific high temperature above an operating temperature at which the chip operates normally and generating a sensing signal; Control means for generating a standby signal for switching to a standby mode in response to the sensing signal and the burn-in signal output from the sensing means; And Mode switching means for switching the chip to the standby mode by blocking a chip control signal for controlling the operation of the chip under the specific high temperature in response to the standby signal output from the control means; By the way, The sensing means, A plurality of MOS Field Oxide Transistors (MOS Field Oxide Transistors) are provided, and the sensing signal is generated by detecting that the absolute value of the threshold voltage of the transistor decreases as the temperature rises. Standby mode switch. The method of claim 1, wherein the sensing means, Optional means including a plurality of first PMOS transistors, each of which receives a plurality of different control signals applied in response to the power supply voltages so as to operate in various power supply voltage environments, respectively; Voltage dividing means having a plurality of second PMOS transistors connected to said option means, and outputting an output voltage having a voltage difference of an arbitrary magnitude by threshold voltages of said plurality of second PMOS transistors in response to said high temperature ; And Switching means for driving in response to an output voltage output from said voltage dividing means and outputting said sensing signal in a switching operation; Standby mode switching device at a specific temperature comprising a. The method of claim 2, An enMOS transistor connected between a power supply voltage and the option means for disabling the standby mode switching device in a burn-in test, and receiving the burn-in signal as a gate. Standby mode switching device at a specific temperature, characterized in that further comprises. The method of claim 2, wherein the switching means, Standby mode switching device at a specific temperature, characterized in that the switching to the difference between the ground voltage and the output voltage output from the voltage dividing means. The method of claim 6, wherein the switching means, And an inverter connected in series to receive an output voltage output from the voltage dividing means. The method of claim 1, wherein the control means, Logic means for receiving the sense signal and the burn-in signal and performing a negative logic to output the standby signal Standby mode switching device at a specific temperature, characterized in that comprises a. The method of claim 8, wherein the control means, And standby mode switching device is disabled in a burn-in test in response to the burn-in signal. The method of claim 1, wherein the mode switching means, And switching the chip to a standby mode by cutting off the chip control signal in response to the standby signal.