JPH04150731A - Power supply - Google Patents

Abstract

PURPOSE:To feed a power supply voltage stably even in case of intermittent use of battery by providing a second switching section wherein a control section at a first load section controls power supply from first and second battery sections to a micro current load section. CONSTITUTION:During low current operation with a voltage lower than a first predetermined voltage, i.e., 3V, only a first load section 8 operates to feed power only from a first battery section 3. When a first switching section 7 is controlled through the first load section 8, first and second battery sections 3, 4 connected in series through a second voltage control section 6 feed power to a second load section 2 operating with a second predetermined voltage of about 5V which is higher than the first predetermined voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to the configuration of a power supply device using a battery. In particular, it relates to a power supply device using a lithium battery to guarantee operation over a long period of several years.

Conventional technology In recent years, the number of devices that use batteries as their main power source has increased, and -
For devices that use rechargeable batteries, in order to guarantee long-term operation, device control must also be set in a low current operation mode (for example, the microcomputer is placed on standby until a predetermined input signal is generated) in addition to the normal operation mode. mode and stop mode). Furthermore, there is a configuration in which an operating voltage is supplied that is lower than a normal voltage in the small current operation mode. A conventional power supply device is shown in FIG.

1 is a first load section that operates at a first predetermined voltage; 2 is a second load section that operates at a second predetermined voltage higher than the first predetermined voltage; and 3 is a first load section that operates at a second predetermined voltage higher than the first predetermined voltage. a first battery section that supplies power, and a second battery section 4 that has a smaller capacity than the first battery section and is connected in series with the first battery section and supplies power to at least the second load section; , 5 is a first voltage control section that produces the first predetermined voltage, 6 is a second voltage control section that produces the second predetermined voltage, and 7 is the first and second battery section connected in series. This is an opening/closing section in which the first load section controls the power supply from the first load section.

The first predetermined voltage is a low voltage, and the first voltage control unit 5 sets a voltage of 3 volts or less to support the small current operation mode.
Further, the second voltage control section 6 generates a normal IC operating voltage of about 5 volts. Here, many configurations use series regulators to suppress switching noise generation, but in this case, the series-connected battery sections 3.4 must secure a voltage higher than 5 volts by a predetermined voltage. . That is, if the battery part 3 and the battery part 4 have the same voltage, it is sufficient to ensure 3 volts or more for each.

With this configuration, if the average current consumption in the normal operation mode that operates intermittently is sufficiently smaller than the average current consumption in the standby mode, the capacity of each battery is determined by the average current consumption determined by both the small current operation mode and the normal operation mode. power is supplied from the first battery section to the first load section, the opening/closing section is controlled by the first load section, and the first and second batteries connected in series Since power is supplied from the first load section to at least the second load section, it is sufficient for each battery to ensure the average current consumption of the load section to which power is to be supplied. That is, the second battery section consumes no current in the mode in which the opening/closing section is controlled and power supply is not performed.

Problems to be Solved by the Invention However, in the above-described configuration, except for the normal operation mode in which the second battery section supplies power, power is not supplied at all by the control of the opening/closing section, and no current is consumed. Therefore, when using a lithium battery with extremely low self-discharge to guarantee long-term operation, a protective film forms on the surface of the lithium negative electrode, which increases internal resistance and causes current to drop in normal operation mode. There was a problem in that when the supply voltage was applied, the balance with the load resistance caused a large drop in the supply voltage.

The present invention solves the above problems, and in addition to having an economical configuration that ensures average current consumption adapted to each operating mode, the present invention provides a power supply device that supplies a stable power supply voltage even when using intermittent batteries. is intended to provide.

Means for Solving the Problems In order to achieve the above object, the power supply device of the present invention includes: a first timer for measuring a first predetermined period; a second timer for measuring a second predetermined period; a first load section that operates at a first predetermined voltage and a control section that outputs a regulation signal in response to signals from the first and second timers; and a second load section that is higher than the first predetermined voltage. the second operating at a predetermined voltage of
a load section, a microcurrent load section that also operates at a second predetermined voltage, a first battery section that supplies power to the first load section, and a capacity smaller than that of the first battery section. a second battery unit that is connected in series with the first battery unit and supplies power to at least the second load unit and the minute current load unit; and the first and second battery units that are connected in series. The first opening/closing section controls the power supply to the second load section by the first load section, and the first switch controls the power supply from the first and second battery sections to the minute current load section. and a second opening/closing section operated by a control section in the load section.

Effect of the present invention With the above-described configuration, power is supplied from the first battery section to the first load section, the opening/closing section is controlled by the first load section, and the first and second connected in series are connected. Since power is supplied from the battery section to at least the second load section, each battery section only needs to ensure the average current consumption of the load section to which power is to be supplied. Furthermore, the minute current load can be connected to the load of the second battery section at a predetermined timing (the second opening/closing section is controlled, so the increase in internal resistance in the second battery section is controlled, and the power supply is stabilized). It will be implemented as follows.

EXAMPLE An example of the present invention will be described below. Components with the same numbers in FIG. 1 as in FIG. 3 have the same functions. 8 is a first load section that operates at a first predetermined voltage; 9 is a minute current load section that operates at a second predetermined voltage;
Reference numeral 10 denotes a second opening/closing section in which a control section in the first load section controls power supply from the first and second battery sections to the minute current load section.

FIG. 2 shows the components of the first load section 8,
11 is a first timer that measures a first predetermined period; 12
1 is a second timer that measures a second predetermined period, and 13 is a control unit that outputs a adjustment signal in response to signals from the first and second timers.

14 is a functional section that controls the first opening/closing section.

That is, during small current operation at a low voltage of 3 volts or less, which is the first predetermined voltage, only the first load section 8 operates, so power is supplied only from the first battery section 3.

Further, when the first opening/closing section 7 is controlled by the first load section 8, the second load section 2 which operates at a second predetermined voltage of about 5 volts higher than the first predetermined voltage The first battery section 3 and the second battery section are connected in series via the second voltage control section 6.
Power is supplied from the battery section 4 of. Therefore, the capacity of the first battery section 3 needs to be equal to the total of the average current consumption in the first load section 8 and the average current consumption in the second load section 2. The capacity of the section 4 only needs to ensure the average current consumption in the second load section 2. In particular, in the case of intermittent operation in which the period in the low current operation mode in which only the first load section 8 operates is long and the ratio in the normal mode in which the second load section 2 also operates is small, the second battery section 4 The capacity of the first battery section 3 can be selected to be considerably smaller than the capacity of the first battery section 3.

Further, by connecting the minute current load 9 to the second battery unit 4 for every first predetermined period measured by the first timer 11 and only for a second predetermined period measured by the second timer 12. In the original normal operation mode, a small current also flows through the second battery section which operates intermittently at intervals shorter than the intermittent period. In other words, the growth of the stable protective film on the negative electrode lithium surface can be kept at a predetermined value, and the increase in internal resistance can be controlled.

For example, in a line terminal network control device that automatically reads gas meters and water meters via telephone lines, the normal operation mode described above is when meter reading is performed once every month or every two months. A milliampere current flows for several tens of seconds. The rest of the period is in a low current operation mode, such as updating the calendar for terminal calls and waiting for external interrupts, so on average only about a few tens of microamperes flows. Therefore, by setting the first predetermined period to several hours and the second predetermined period from several seconds to several tens of seconds, by flowing a minute current of several microamperes,
Internal resistance can be suppressed from several tens of ohms to about 100 ohms. If this minute current load is not connected, the internal resistance of the second battery section may reach several hundred ohms to several kiloohms, and if you try to supply voltage in normal operation mode, it will cause an extreme voltage drop. Become.

Here, the current supplied by the minute current load is extremely short in operating period compared to the interval of non-operating period, so the average current does not matter much in terms of the capacity of the battery section.

The first and second battery sections of the present invention may each be composed of one battery, and in order to obtain the predetermined voltage of 3 volts or 5 volts as in the above-mentioned example, It is effective to use a lithium battery with an output voltage. As described above, the present invention is a device that guarantees long-term operation, and is an effective invention especially when using a primary battery.

Effects of the Invention As is clear from the above explanation, the present invention has the following advantages:
It is necessary to secure the total of the average current consumption in the first load section and the average current consumption in the second load section, but the capacity of the second battery section is the same as the average current consumption in the second load section. Since only the average current consumption needs to be ensured, an appropriate battery capacity can be selected from the average current consumption. That is, the capacity of the second battery part can be reduced compared to the capacity of the first battery part, and the capacity can be small, which is economical in configuring the power source. In addition, since the second opening/closing section is controlled so that a minute current that can be ignored as an average current flows through the second battery section at a predetermined timing, the increase in internal resistance in the second battery section is controlled and the stability is maintained. This has the effect that it is possible to supply a high power supply.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a power supply device according to an embodiment of the present invention, FIG. 2 is a block diagram of a first load section of the same device, and FIG. 3 is a block diagram of a conventional power supply device. 2...Second load section, 3...First battery section, 4...Second battery section, 7...First opening/closing part, 8...first load part, 9...
...Minor current load section, 10...Second opening/closing section, 11...First timer, 12...
Second timer, 13...control unit. Name of agent: Patent attorney Akira Okaji et al. Figure 28

Claims (1)

[Claims] A first timer that measures a first predetermined period, a second timer that measures a second predetermined period, and control that outputs a adjustment signal in response to signals from the first timer and the second timer. a first load section that operates at a first predetermined voltage, and a second load section that operates at a second predetermined voltage higher than the first predetermined voltage; a first battery section that supplies power to the first load section; a first battery section that has a smaller capacity than the first battery section and is connected in series with the first battery section; a second battery section that supplies power to the second load section and the minute current load section; and a second battery section that supplies power to the second load section from the first battery section and second battery section connected in series. a first opening/closing section in which power supply control is performed by the first load section;
A power supply device comprising a battery section and a second opening/closing section in which a control section in the first load section controls power supply from the second battery section to the minute current load section.