JPH0439718A - Memory card power source energizing device - Google Patents

Abstract

PURPOSE:To prevent the data from breakdown in a volatile memory IC by supplying the power from a built-in auxiliary power source even if an external power source of a memory card power source energizing device is disconnected instantaneously. CONSTITUTION:This device is provided with a means 2 for backing up plural pieces of volatile memories ICs 101 - 10n, and supplying a power source from the outside of a memory card in order to prevent the consumption of a built-in battery 9, and a control means 23 for preventing the breakdown of holding data caused by stepdown of an internal voltage of the memory card due to the slow fluctuation of an external input voltage. Also, this device is provided with a means for supplying the power source to the memory card by an auxiliary power source 22 incorporated in a main body even if an energizing device is disconnected instantaneously, a battery voltage detecting means 26 for informing a replacement time of the internal battery 9, and a means 23 for preventing erroneous write in the case of inserting and drawing out the memory card. In such a manner, the breakdown of holding data of the volatile memory IC caused by consumption at the time of backup of a memory and inserting and drawing out a hot-line, etc., can be prevented.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a Z memory card with a built-in volatile memory card, and in particular, to reduce battery consumption and live wires during memory backup using the internal primary battery of the memory card. This provides a structure to prevent destruction of retained data due to insertion/removal, etc.

[Conventional technology]

FIG. 2 is a block diagram of a conventional memory card incorporating a plurality of volatile memory ICs.

In the figure, reference numeral 3 denotes a power supply voltage detection device 0 that monitors the 5V power supply voltage for the memory card supplied from an external output power source (not shown) through the memory card external power supply terminal 14, and this power supply voltage detection device 03 is the first one. 1 output terminal 5 is PNP
) is connected to the base of the transistor number, and its output controls the on/off of the transistor 4 to switch between an external power source, such as a FiBWt source, and an internal power source 6.

In addition, the memory card input terminals 15-151 are connected to the input buffer x012 side, and the input terminals 7a 012 are supplied to several volatile memories 0101 to 10n constituting the memory card body. These volatile memory devices 0101 to 1021 are commonly connected to the power line on the left side of the transistor 4 that switches between the external 5-power source and the internal power source 6, and the power source line is connected to a diode for backflow prevention and a current-limiting resistor. Over time, a primary battery 9 is connected as an internal power source 6, and this primary battery 9 backs up the data held in each volatile memory 0101 to 10n. 11 is a resistor for determining the input level, and 17 is an OV power supply input terminal.The 0th order operation will be explained. During memory backup, that is, when the external 5V power supply voltage is 4.25V or less, the power supply voltage detection I03 detects it and turns off the output of the first output terminal 5, that is, the sink current, and the P
NP) The transistor 4 turns off and switches to the internal power supply 6. The input terminals 151 to 15n are input level determining resistors 1, ! SI) Becomes rLJ through the countermeasure resistor 1. At this time, when the voltage applied to the input terminals 151 to 15!1 changes slowly, the input buffer l012 becomes 0V.
In the case of the OS type, when the input voltage becomes around 1/2V of the power supply voltage, a current flows, causing the internal voltage 6 to drop and potentially destroying the data in the memory card. Memorie C101~1
When retaining the data in the memory, the power supply voltage is often supplied from the primary battery 9.

Next, if a power outage occurs while the power supply voltage is being supplied from the external power input terminal 14, the data is retained by the power supply voltage supplied by the primary battery 9 in the memory card.

Next, if the data in the volatile memory cells 0101 to 1 within the memory card is held by the primary battery 9 in the memory card, the lifespan of the primary battery 9, that is, when to replace it is unknown. When hot insertion/removal is performed, there is a possibility that the data in the internal volatile memory areas 0101 to 1011 will be destroyed.

[Problem to be solved by the invention]

Conventional memory cards are configured as described above, so when using a memory card back amplifier, the input level of the input terminal must be fixed to "H" or rLJ.
In addition to supplying only the primary battery inside the memory card, it is necessary to have a means to retain the data in the memory card and to notify when it is time to replace the primary battery. Sometimes the data in memory 0 is destroyed (
There were problems such as incorrect writing.

The present invention was made to solve the above-mentioned problems, and can prevent the primary battery in the memory card from being consumed.
Furthermore, it prevents the internal voltage of the memory card from dropping due to fluctuations in the external power supply voltage, and even if the external power supply is momentarily interrupted, the power supply voltage can be supplied to the memory card, and even when the memory card is powered on, the internal primary The purpose is to be able to detect when it is time to replace the battery and also to be able to hot insert and remove a memory card.

[Means to solve the problem]

The memory card power source energizing device according to the present invention supplies a 5vt source voltage from the external source input terminal to the outside in order to prevent the primary battery in the memory card from being exhausted, and the power source voltage from the external power input terminal is gradually applied. A voltage monitoring circuit is installed to prevent the internal voltage of the memory card from dropping due to gradual voltage fluctuations on the input line. Switches to the secondary battery of K[#,! to supply power voltage to the memory card. It is equipped with a battery voltage detection circuit to store the memory card with electricity and to notify when it is time to replace the internal primary battery, and also sets all input power lines to the rHJ level when inserting or removing the memory card hot. , a means is provided to prevent the data on the memory card from being destroyed (erroneously written).

[Effect]

The memory card power supply energizing device of the present invention can extend the life of the internal primary battery by supplying an external power supply voltage to the memory card, and furthermore, can extend the life of the internal primary battery by supplying an external power supply voltage to the memory card. It is possible to prevent the internal voltage from dropping by performing signal control, and the external power supply and internal secondary battery switching circuit can supply power voltage to the memory card even in a power outage.Furthermore, the battery voltage can be detected even when the memory card is energized. Depending on the circuit, internal 1
It is possible to notify when it is time to replace the next battery, and further, by setting all input lines of the memory card to the "H" level, it is possible to prevent data destruction (erroneous writing) in the memory IC during hot insertion/removal.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a memory card external electrical device and a memory card according to an embodiment of the present invention. In the figure, 18 is an external power supply input terminal, 19 is an external power supply, and 20 is a power supply voltage monitoring circuit that performs switching control between the external power supply 19 and the secondary battery 22.
When the power supply voltage of 9 becomes 6V or less, the secondary battery 22
The power supply is switched to the memory card external power terminal 14.
energized through the first output terminal 5 of the battery voltage output 03
PNP which sucks in electricity and switches between the memory card external power supply 2 and the memory card internal power supply 6) turns on the transistor number, turns off the supply from the internal primary battery 9, and writes multiple volatile memos! The card internal circuit consisting of J I 0101 to 10n shall be operated.0 As a result,
The battery life of the internal primary battery 9 can be extended.

Next, the input line signal control circuit 23 is connected to the memory card input terminals 151 to 15n, and when the power supply voltage of the external power supply 19 becomes 4V or less, the input line signal control circuit output terminals 241 to 24m are connected to the memory card input terminals 151 to 15n. 1
Generate rLJ level output through 5n, set all input voltages μ of input cover 7Ae 012 to “L” level,
It is possible to prevent a through current phenomenon due to gradual fluctuations in the input signal, and to prevent voltage drop of the memory card internal power supply supplied by the internal primary battery 9.

Next, the battery voltage output A is connected to the battery voltage output terminal 16 from between the ten pole side of the internal primary battery 9 and the current limiting resistor 8, and the battery voltage is supplied to the battery voltage detection circuit 26, and the battery voltage becomes 2.5v or less, the battery voltage detection circuit 26
A signal is output from the display output terminal 28 to the display section 25,
Is displayed.

Next, even if the memory card is inserted or removed while the power is being supplied, the output level from the input line signal control circuit output terminals 241 to 24 of the input line signal control circuit 23 is 47 or higher if the power supply voltage of the external power supply 9 is 47 or higher. is rHJ, each load signal of the memory card becomes rHJ level, and data destruction (erroneous writing) in the internal volatile memory units 01 to 10n can be prevented.

〔Effect of the invention〕

As described above, according to the present invention, by energizing the memory card, consumption of the primary battery inside the card is prevented, and even if the external power supply is momentarily interrupted, the memory is supplied by the built-in secondary battery. This prevents the memory card's internal power supply voltage from dropping due to the through current phenomenon that occurs when the external power supply gradually drops or fluctuates when the card is powered on, and replaces the internal primary voltage even when the memory card is powered on. Not only can the timing be known, but when a memory card is hot inserted or removed, the input signal is set to the "■" level, which has the effect of preventing data destruction (erroneous writing) in the memory IC.

[Brief explanation of drawings]

Figure 1 shows part 5 of the present invention! FIG. 2 is a block diagram of a memory card power supply device and a memory card as an example. FIG. 2 is a block diagram of a conventional memory card. In the figure, 1...Resistor for ICgD countermeasure, 2...Memory card external power supply, 3...Battery voltage output 0.4...
・PNP) transistor, 5... 1st output terminal, 6...
...Internal power supply, 7...Reverse current prevention diode, 8...
・Current limiting resistance, 9...Primary battery, 101-10.・
・・Volatile memory 0.1U・・Resistor for determining input voltage μ, 12・・Input buffer 77IO, 13・・Input signal line, 14・・Memory card external power supply terminal, 151~1
5! l...Memory card input terminal, l6...Battery voltage terminal, 17...Ov power supply terminal, 18...External power supply hexagonal terminal, 19...External power supply, 20...Power supply voltage monitoring circuit, 21-... External output power supply, 22... Secondary battery, 23... Input line signal control circuit, 241 to 24n
...Input line signal control output terminal, 26...Display unit, 26...Battery voltage detection circuit, 8F...Battery voltage detection input terminal, 2nd...Display output terminal 0 Note that in the figure , the same code indicates the same or equivalent part 0

Claims (1)

[Claims] In a memory card that includes a plurality of volatile memory ICs and is capable of backing up the data held in the volatile memory ICs with an internal battery, an external A means for supplying power, and a means for providing a control circuit to prevent destruction of retained data due to a drop in the internal voltage of the memory card due to gradual fluctuations in input voltage when the power supply stops momentarily; A means for providing a voltage control circuit so that power can be supplied to the memory card using a secondary battery built into the main body, and a memory card capable of backing up data held in the volatile memory IC using an internal battery, is stored in a power supply device. Even in the case where the memory card is installed, there is a means for providing a battery voltage detection circuit to notify the replacement time of the internal primary battery of the memory card, and when the memory card is inserted and removed using a power supply device,
A memory card power supply device characterized by being equipped with a circuit that prevents erroneous writing.