JPS62167484A - Apparatus for detecting and displaying voltage change - Google Patents

Abstract

PURPOSE:To make it possible to respectively and separately display detected voltages at the times of the rising in voltage and voltage drop by reduced power consumption, by using ECP (electrochromic display) as a display body. CONSTITUTION:ECD is constituted of a display electrode substrate 1 comprising a transparent plate, a membrane metal display electrode 2 comprising tin oxide having a necessary character pattern formed to one surface thereof, an opposed electrode substrate 3 having an opposed electrode formed to one surface thereof, a separator 5, an electrolyte 6, a spacer 7, an expoxy resin 8, a terminal 9 for a display electrode and the terminal 10 for the opposed electrode. This ECD can change drive voltage according to the kind of a display substance and that of an opposed electrode material. As a DC voltage power source 11, for example, a battery of 1.5V is used and, when the voltage of the battery reaches 1.2V or less, a transistor 16 is brought to a continuity state and ECD18 performs display. When the voltage of the battery reaches 1.46V or more, said voltage is divided by resistors 22, 23 and, when the divided voltage is applied to the base electrode of a transistor 25 through a resistor 24, the transistor 25 comes to a continuity state and ECD 26 performs display.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a voltage change detection display device using a display body exhibiting an electrochemical display phenomenon (electrochromic display, hereinafter abbreviated as ECD), and in particular to a voltage change detection display device having the following features. The purpose is to provide a device.

In other words, ■ the voltage to be detected, for example, when the voltage of the power supply falls below the desired detection voltage, the display is performed by the voltage to be detected, ■ the power consumption is low, and ■ the display is clear even in bright places. The object of the present invention is to provide a voltage change detection and display device having the following features: (1) being constructed with a simple drive circuit;

Conventionally, small voltmeters, light emitting diodes, and the like have been widely used as power supply voltage detection devices for portable devices. Since these require a relatively large current for voltage detection and display, they can only be applied to portable devices with a large power supply capacity, such as pagers, small radios, electric razors, small tape recorders, electronic clocks, cameras, etc. Such a voltage change detection and display device cannot be applied to equipment with a small power supply capacity, and even if such a device is applied, it must be operated only when detecting and displaying the power supply voltage, which is inconvenient. Furthermore, in the case of voltage change detection display devices using light emitting diodes, it is difficult to see the display in bright places, and a booster circuit is required for clearer display or when the power supply voltage is low, making it expensive. It has drawbacks such as being expensive.

The present invention provides an extremely excellent device that overcomes the above-mentioned conventional drawbacks by using ECD in a voltage change detection display device.

First, ECD will be explained with reference to FIG.

In FIG. 1 A, 2, 1 is a display electrode substrate made of a transparent plate, on one surface of which a thin film metal display electrode 2 made of tin oxide, indium oxide, etc. is formed in the required character pattern, and this thin film metal Portions other than the display electrode 2 are insulated with glass, 3102, or the like. 3 is a counter electrode substrate, and a counter electrode is formed on one surface thereof. 6 is a separator, 6 is an electrolytic solution, 7 is a spacer, 8 is an Epoquine resin, 9 is a display electrode terminal, and 1Q is a counter electrode terminal.

Other ECD configurations include one in which a display electrode 2 and a counter electrode 3 are provided on a counter electrode substrate 3 as shown in Figure 2, and one in which two 0ECDs are combined as shown in Figure 3. .

ECDs that utilize these electrochemical display phenomena include: ■ those that utilize electrochemical reversible precipitation reactions of metals or iodine compounds, and ■ those that utilize electrochemical reversible P on metal surfaces.
There are many types such as those that utilize H change reaction, ■ those that utilize electrochemical reversible coloring reaction of organic substances, and ■ those that utilize electrochemical reversible color change of metal oxides such as tungsten oxide and molybdenum oxide. There is. The driving voltage of these 0ECDs can be changed depending on the type of display material and counter electrode material, and the driving voltage can also be changed depending on whether the electrolyte used is a solid electrolyte, an organic electrolyte, or an aqueous electrolyte.

In particular, when an aqueous electrolyte is used, the ECD can be operated with an ECD of 1.5 or less. Furthermore, since these ECDs are non-luminous, their display is extremely clear even in bright places. Furthermore, the power consumption of these ECDs is proportional to the amount of electricity used for displaying and erasing, and is determined by the area of the display body. Since the substance has memory properties, power consumption can be further reduced.

It is generally known to take advantage of these advantages of ECD and use it for digital displays such as electronic clock displays, calculator displays, and automobile meter panels.

The present invention focuses on the fact that the ECD can be driven once at a particularly low voltage, for example, 1.15 V or less, and achieves the intended purpose by using the ECD in a voltage change detection display device.

Since the collector-emitter of the transistor 16 becomes conductive, no current flows through the ECI:zs and the ECD 18 does not display any information. Thereafter, the voltage of the DC power supply voltage 11 is set to the desired detection voltage, for example 1. When Ov is reached, the transistor 16 is cut off, so current flows to the ECD18 and the ECDla
performs display.

The specific configuration of the above embodiment is such that, for example, a 1.6-inch battery is used as the DC power supply voltage 11, and a resistance of 13° and 14.1° is used.
6, 17. Each value of 19 is 160Ω.

150 is Ω, 0.1 sKΩ, 26 is Ω, QΩ, C539 is used as the transistor 16, ECD 18 is n-dioctyl-4-4'-dipyridine! Umdichloride 10.3M potassium chloride was used, and silver was used as a counter electrode.

Note that the cell display area of ECDl 8 was 0.04 cA, and the minimum drive voltage was approximately 500 mV.

As a result, when the battery voltage decreased from 1.5 to 1.0, the transistor 16 was cut off and the ECD 18 displayed a voltage drop in purple. At this time, the current flowing through the ECD 18 was about 30 μA.

Next, an embodiment of the present invention will be described with reference to FIG.

FIG. 4 is an electrical circuit diagram of a voltage change detection and display device that detects and displays the end of charging and discharging of a secondary battery.

When the battery voltage was 0.6V, the current flowing through the ECD 18 was about 1oμA. Then, when the switch 12 was opened, the display of ECDl 8 disappeared.

On the other hand, a voltmeter, L
Similar experiments were conducted using ED miniature light bulbs, but none of them were able to display at such low voltage and current.

In addition, when diP-cyanophenyl, 4,4'-dipyridinium dichloride, which is one of the diviridinium compound dielectrics, was used as the display substance of ECDls in the above example, a green display was obtained.

Note that when the transistor 16 is cut off, the ECD
In order to increase the current flowing through l8, transistor 1
6 may be connected in Darlington and amplified.

In FIG. 4, reference numeral 21 denotes an lfh concubine 4 charging and discharging device that charges and discharges the DC voltage power supply 11.

For example, a 1.6V battery is used as the DC voltage power source 11, and when the battery voltage becomes, for example, 1.2V or less, the transistor 16 becomes conductive, and current flows to the ECD 18, and the ECD1B performs display.

Conversely, if the battery voltage is, for example, 1.46V or higher,
When this battery voltage is divided by resistors 22 and 23 and applied to the base electrode of transistor 26 via resistor 24, transistor 26 becomes conductive. At this time, ECD26
A current flows through the ECD 26, and the ECD 26 performs display. Note that resistors 27 and 28 are protective resistors for E CD 26.

In this embodiment, by displaying the ECDls and ECD26 with different letters such as E, F, etc., or in different colors, the charge/discharge state of the battery can be identified very easily.

The ECD used in the present invention will be explained in more detail below.

A SiO thin film is used as the electrolyte, the display electrode is formed by depositing a tungsten oxide thin film on a tin oxide thin film, and the counter electrode is a tungsten oxide ECD made of gold.When the cell display area is 0.04 ci, driving The minimum voltage will be approximately 4■.

Therefore, the power supply voltage needs to be at least 4.0μ or more.

Now, when the power supply voltage is set to aoV and the desired detection voltage is set to 5.0■, when the power supply voltage becomes 6.0V or less, a current of about 1 mA flows through the ECD, and the ECD displays a blue color. Note that in order to immediately erase the ECD display, it was necessary to apply a reverse voltage of -2V.

Further, when a porous lead electrode was used as a counter electrode in a tungsten oxide 0 ECD and 8M H2BO3 was used as an electrolyte, the driving voltage of this ECD was 0.7V. This E
Applying CD to the electric circuit shown in Fig. 4, resistors 13 and 14
, 15, 17.19 to 0.7 KΩ, 1.5 to Ω
, 0.16, Q, 0.12 KO, Ofl, when the power supply voltage becomes 1 V or less, a current of about 1 mA flows through the ECD, and the ECD displays a blue color.

Note that in order to immediately erase the ECD display, it was necessary to reverse the polarity of the applied voltage.

In addition, as an ECD that utilizes an electrochemical chemical precipitation reaction of metals, iodine compounds, etc., the display electrode and counter electrode are made of a metal that is inert to the electrochemical display reaction, such as PT, and a fourth A grade pyridinium iodide/KI solution was used. When this ECD is applied to the electric circuit shown in FIG. 4, a current of about 1 mA flows during the voltage drop detection display, and it is necessary to reverse the current.

As is clear from the above explanation, the use of ECD as a display body of a voltage change detection display device has two advantages: (1) the power consumption is extremely low during ECD cell operation and non-operation; (2) the detected voltage power source is e.g. Even if it becomes less than 1v,
It is possible to display voltage drop detection on the detected voltage power supply, and by using an ECD that displays 02 or more colors, it is possible to display the detected voltage separately with low power consumption when the voltage rises and falls. ■These ECD cells have an extremely simple structure and can be mass-produced, so they can be provided at a much lower cost than LEDs, voltmeters, etc.; ■They are simple and easy to use. It has the advantage that it can easily be used as a voltage change comparison display device using a known drive circuit. As an ECD for a voltage change detection display device, in particular, a display that utilizes the electrochemical reversible coloring reaction of an organic material does not require reversing the polarity of the voltage applied to the ECD cell in order to erase the display state. In addition, by utilizing the characteristics such as particularly excellent color display and image memory properties, it becomes an excellent voltage change detection display device. By applying these voltage change detection and display devices to portable electronic devices that use batteries as a power source, they can help extend the battery life when using secondary batteries, and the same applies when using secondary batteries. Being able to know in advance when the battery is nearing its end of discharge has the effect of greatly increasing the commercial value of the portable device.

[Brief explanation of drawings]

Figure 1A is a side sectional view of the first ECDO used in the present invention, Figure 1 is a front view of the same ECD, Figure 2A is a side sectional view of the second ECDO used in the present invention, Figure 2 Mouth is 4ECD
3A is a front view of the third ECD used in the present invention.
3 is a front view of the same ECD, and FIG. 4 is an electric circuit diagram of a voltage change detection and display device showing an embodiment of the present invention. 11...DC voltage power supply, 16.25...
・Transistor, 18.26... Name of ECD0 agent Patent attorney Toshio Nakao and one other person Figure 1 (a) (b) Figure 2 b) ('O) Figure 3 (a) (b) Figure 4

Claims (2)

[Claims] (1) A DC power source and a first power source connected in parallel to the DC power source.
, a second voltage dividing circuit, first and second active elements connected to the voltage dividing points of the first and second voltage dividing circuits, respectively, and on/off operations of the first and second active elements. comprises first and second ECD elements that generate color in accordance with the voltage, and when the power source is at a predetermined voltage, the first active element is in an off state, the first ECD element is in a coloring state, and the second active element is in an off state. in a state in which the second ECD element does not produce color; when the power source is below a predetermined voltage, the first active element is in an on state and the first display element does not produce color;
A voltage change detection display device characterized in that when the second active element is in an on state, the second display element is in a coloring state. (2) The voltage change detection and display device according to claim 1, characterized in that a charging/discharging circuit is connected in parallel to a DC power source.