KR930000009B1 - Power supply control apparatus of lap-top computer and control method therefor - Google Patents

Abstract

The circuit checks the power charging/discharging states of the battery as reguired and distributes the power effectively to each circuit requiring the necessary power. The circuit comprises a host circuit (1) having a CPU, memory, nd peripheral circuit, an output circuit with LCD, a rechargable battery, a PMSC (4) controlling the rechargable battery to minimize the self power consumption, and a photoresistor (5) connected between the PMSC and the host circuit. The PMSC comprising a peripheral circuit controller (5) and a one chip microprocessor (6) controls the peripheral circuits of the laptop computer with the controller (5).

Description

Power supply controller of laptop computer and its control method

1 is a block diagram showing a device configuration of the present invention.

FIG. 2 is a circuit diagram showing in detail the battery charging and discharging and a circuit related thereto in FIG.

FIG. 3 is a circuit diagram of FIG. 1 embodied for power supply control supplied to an output device.

4 is a circuit diagram of a micro switch of a laptop computer.

FIG. 5 is a flowchart showing a battery charging / discharging and a control method related thereto according to FIG.

FIG. 6 is a flowchart illustrating a power supply control method supplied to an output device in FIG.

* Explanation of symbols for main parts of the drawings

1: Host 2: Power Supply

3: output device 4: PMSC

5: peripheral device control circuit 6: processor unit

7: battery fast charging circuit 8: adapter voltage sensing unit

9: Battery voltage search circuit 10: Low battery voltage display circuit

11: LCD power supply control circuit 12: LCD VLCD voltage control circuit

13 LCD backlight control circuit 14 micro switch control circuit.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laptop computer, and more particularly, to a power supply control apparatus for a laptop computer and a control method thereof for efficiently using a battery power to minimize power consumption of a laptop computer using a battery.

Compared to the desktop type computer, the laptop type computer is small, portable and can be moved from time to time, and can be easily used by a user at any place. The schematic structure of the computer is a memory device, a CPU and related peripheral circuits. It is a well-known fact that the power supply required for using a laptop computer must be efficiently used, as it is composed of a system main body and an output device implemented as an input device, a keyboard and an LCD, and a battery as a power supply device.

In order to make full use of the power by the battery, not only charging and discharging batteries are used, but also the voltage supply of the charged battery requires time constraints, so the power consumption used throughout the system should be minimized as much as possible.

In response to such inevitable demands, the present invention frequently checks and operates the state of charge and discharge of batteries so as to efficiently use the power of the battery for charging and discharging, and controls the power supply for each device of the computer that requires power. It is an object of the present invention to provide a power control device for a laptop computer.

It is another object of the present invention to provide a method for more effectively operating a device implemented according to the above object.

The apparatus of the present invention comprises a host unit 1 constituting the main body of a laptop computer, a power supply unit 2 of a battery and an output unit 3 of an LCD, as shown in the block diagram shown in FIG. The unit 1 is connected to the power supply device and the output device by a PMSC 4 and a port register PR connected between the PMSC and the host.

For example, a port register can consist of a buffer and a D flip-flop, which is configured for data input / output between PMSC and host.

Although not shown, the host unit, the power supply, and the output device are organically connected to each other.

The PMSC 4 is composed of a peripheral device control circuit 5 and a so-called one-chip microprocessor 6 (hereinafter, referred to as a processor). The one-chip microprocessor internal configuration is an A-converting analog signal to a digital signal without shown. / D converter and vice versa D / A converter, CPU, memory device, etc. are provided, and the peripheral device control circuit (5) retrieves the status of each peripheral device of the laptop computer and communicates with the host unit (1). It is configured to control via the peripheral device control circuit 5 while taking.

Hereinafter, the configuration and operation effects will be described in detail with reference to FIGS. 2 to 4 as detailed embodiments of the peripheral device control circuit, and FIGS. 5 and 6 which are flowcharts describing an operating method according to the apparatus.

Since the battery uses a battery that can be charged and discharged as a power supply for a laptop computer, a battery charging adapter (not shown) that converts AC power into DC is used for charging. The output voltage is retrieved by the processor unit 6 of the PMSC via the adapter voltage sensing circuit 8 shown in FIG. In the drawings, the same reference numerals are the same as each other.

In addition, the output terminals PB0-PB7 of the processor unit describe only terminals necessary for technology.

The adapter output voltage, for example, the voltage level of 13 V is divided by the resistors R1 and R2 and input to the processor unit of the PMSC through the PD2 terminal. This analog voltage level is converted into digital and converted into a ROM in the processor unit. The size is recognized based on the software of the present invention as shown in (not shown).

On the other hand, in the embodiment of the present invention for the fast charging of the battery circuit shown in the reference numeral '7' of FIG. 2 is configured between the adapter and the battery and the signal controlling the operation of the circuit through the 'PB4' terminal of the processor unit Connected to the output. That is, when the adapter is connected, the battery is rapidly charged. At this time, it is necessary to determine whether or not the adapter is installed. Therefore, the adapter voltage sensing unit 8 detects whether the adapter is installed and the magnitude of the voltage (when the voltage is less than the predetermined voltage, it does not operate. Therefore, the high signal is applied to the transistor Q21 of the battery quick charge circuit 7 by turning on the transistor Q21 and the transistor Q20 is turned on in conjunction with the 'PB4' terminal of the processor unit. In addition to being rapidly charged, the LED emits light as an indicator, and the user can know from the outside that it is being charged.

The reference symbol 'Ts' is a temperature sensor connected between the LED and the ground to control charging. To explain this, it is known that the battery temperature of the battery during charging affects the frequency of battery charging and discharging, so that charging is stopped at the proper temperature and charging is started again when the temperature drops to the desired value. That is, since the temperature sensor leading to ground does not open when the temperature rises and forms a closed loop, the transistor Q21 and the LED 1 are turned off so that rapid charging does not occur.

After the rapid charging to the battery as described above, the charge should be cut off when the voltage is completely reduced. Of course, at this time, the indicator LED1 flashes to indicate that charging is completed. This is done through the battery voltage search circuit 9 which checks the battery voltage of FIG. Of course, this circuit is not limited to this function, and as will be described later, it also functions to always search for the voltage of the battery used for a long time.

This circuit is composed of voltage divider resistors R5 and R6 and OP amplifier OP1 as a buffer as shown in the figure. The input battery voltage is converted into an analog voltage value of a predetermined level through this circuit, converted into a digital value by an A / D converter in the processor unit, and the built-in software determines the completion of rapid charging. Since the voltage level decreases when the current continues to flow after the battery is fully charged, the voltage decrease is detected after the battery is fully charged. In the PB4 of the processor, the output is turned low to stop the charging.

At this time, since the battery charge is controlled by the PMSC as a feature of the present invention, it is possible to control the battery charge without driving the host unit.

As already pointed out, in the battery voltage search circuit of FIG. 2, when the supply voltage level drops below a predetermined value according to the use of the battery, the embodiment outputs a 'warning message' through an output device and at the same time 'alarm sound'. Outputs

Also, as shown in FIG. 2, when the inverter IN1, the resistor, the transistor Q23, and the LED2 are connected and the battery voltage drops below a predetermined level, as shown in the configuration of the low battery voltage display circuit ID shown in FIG. It outputs high signal through PB2 'terminal and turns on LED2 so that the status can be seen from outside.

In addition, when a command to report the current state of the battery from the host to send a corresponding message according to the state of charge and discharge. This is, of course, possible with some software and the battery voltage detection circuit of FIG.

Next, an output device of a laptop computer composed of an LCD will be described.

In order to provide various data or results to the user, a computer needs an output device, and a laptop uses an output device composed of LCDs in view of small light weight and low power consumption. In order to drive this, the LCD's power supply voltage, backlight voltage, and VLCD voltage are used. This is desirable.

This voltage, which is always needed to drive the outputs, is supplied by the battery and needs to be operated efficiently.

First, the power supply voltage VDD of the LCD will be described. As shown in FIG. 3, the VDD control circuit is composed of resistors R13-R15, transistors Q31, and Q32. The basic idea that the power supply voltage control circuit 11 of the LCD is configured is to control VDD, which is one of the LCD driving voltages, to match the LCD on / off sequence to minimize power consumption.

In order to control the VDD supply, a control signal is output from the 'PB7' terminal of the processor unit. According to this circuit, it is possible to control the minimum voltage when VDD is on and VDD is off.

That is, since the transistor Q31 is turned on and the transistor Q23 is sequentially turned on, when the VDD voltage is supplied to the LCD, the base of the transistor Q31 depends on the collector current of the transistor Q31 required to turn on the transistor Q31. The current can be minimized such that the output of the 'PB7' terminal of the processor unit is approximately 1.18V. This value may vary depending on the integer value of the resistor, but in this embodiment, the integer values of R13-R15 are calculated as 10K, 1K, and 10K, respectively.

In addition, when the VDD is off, the voltage level output from the processor unit 'PB7' is 1 V or less as described above, so that the transistor is turned off, so the VDD supply is cut off.

Next, the VLCD voltage control circuit 11 of the LCD will be described.

This circuit controls the VLCD which is one of the LCD driving voltages in order to match the on / off sequence of the LCD similarly to the VDD voltage control circuit. As shown by reference numeral 12 in FIG. The output terminal is connected to the base of transistor Q34 via inverter IN2 and resistor R16, and the VLCD input voltage (voltage level is + 21V, for example) is connected to the collector of transistor Q34. ) To VLCD output.

When the VLCD is turned on, according to the processor unit 'PB1', when the output of about 2.0 V or more is output as the minimum voltage for turning on the transistor Q34, the transistor is turned on. Thus, the transistor Q35 is turned on and the VLCD is applied to the LCD. .

In addition, when the VLCD is turned off, the transistor Q34 is turned off by setting the output of the PB1 to 0.8 V or less so that the transistor Q35 to which the VLCD voltage is applied is turned off.

The LCD on / off sequence control described above is designed to drive the LCD driving voltage, that is, the voltages of VDD and VLCD in the order of video signal → VDD → VLCD according to the video signal to be displayed on the LCD in order to eliminate the abnormal phenomenon occurring in the LCD when the power is turned on. As such, this control is feasible as a circuit considering the low power consumption described above.

In addition, the driving voltage described above as well as the voltage for the LCD backlight must be supplied to the LCD.

At this time, the LCD backlight on / off control is controlled as the high and low signals of the processor unit 'PB6' in this embodiment.

The circuit configuration implementing this is the same as the circuit shown by 13 in the reference section of FIG.

This circuit is realized by using a voltage regulator VR whose input voltage + 12V varies in output voltage in accordance with the ratio of the resistors Ra and Rb. The control terminal for variable output voltage of the voltage regulator VR which is commercially available is an 'Adj' terminal, and a switching transistor Q33 is connected thereto, and a voltage regulating resistor Ra and Rb is connected to the collector of the transistor. have.

In this circuit, the output voltage is given as C (1 + Rb / Ra) (where C is a constant value given as a circuit constant) so that the output voltage is adjusted by adjusting the variable resistor 'Rb'. Since the variable voltage needs only a voltage corresponding to the LCD backlight on / off, when the variable resistor Rb becomes 0Ω, the backlight is turned off because the C value is given as 1.25 according to the present embodiment. Since the transistor Q33 is turned on, the voltage regulator adjust terminal clearly corresponds to an Rb value of 0?, So that the transistor Q33 can be turned on by outputting a high signal at the PB6 terminal of the processor unit.

In other words, the LCD backlight can be turned on / off when high and low signals are output from the 'PB6' terminal of the processor unit.

In terms of utilizing these functions, the PB6 terminal of the processor unit may output a high signal to turn off the backlight of the LCD in order to reduce power consumption when there is no input from the keyboard as an input device for a predetermined time.

Therefore, when the backlight is kept off until the next key input, if any key input is detected according to a predetermined program, the 'PB6' terminal of the processor unit outputs a low signal to turn on the LCD backlight.

In addition, as a matter of LCD backlight on / off, a laptop computer can use a monitor as needed even if it uses LCD as an output device. Therefore, when the monitor is used as an output device, a low signal outputs a voltage of 0.8 V or less through the 'PB6' and PB1 terminals of the processor unit according to predetermined software so as to automatically turn off the LCD backlight and the above-described VLCD.

When the user switches the micro-switch on while the system is supplying power to the laptop computer, ie closes the panel while the power is on, the + 5D voltage is supplied to the PD7 terminal of the processor as shown in FIG. The micro switch control circuit 14 is configured to interrupt the supply. In the figure, the resistor R40 and the capacitor C40 are configured for debounce related to the switch μ-S.

Software as a method of operating the apparatus in accordance with the above description will be described in detail below with reference to the flowcharts of FIGS.

The battery charge is charged by the adapter as already described, which is in accordance with the circuit operation of FIG.

Before determining whether the adapter is connected or not, the software of the present invention is searched for the magnitude of the battery voltage as shown in steps 5-1 to 5-4 of FIG. A non-maskable interrupt (NMI) connected to the system interrupts the host's CPU, which then emits a warning message and outputs a 'beep' or PMSC flashes a red LED for visual effect. (See Figure 2)

In this state, the PMSC repeatedly searches whether the adapter is connected. This search is performed through the adapter voltage sensing unit 8 of FIG.

When the adapter is mounted, as described above, charging is started by outputting a high signal from the processor unit 'PB4' terminal in the PMSC (step 5-5). Then, the battery voltage is detected, and the charging is completed (step 5-6). )

In the above charging process, in particular, the steps 1 and 3 will be described in more detail. Since the battery voltage is frequently searched for, the predetermined voltage value is detected by setting a specific register in the processor unit of the PMSC as a counter in the vicinity thereof to detect the predetermined voltage value. When the number of times is met (e.g., 3 times), PMSC sends NMI signal to the CPU of the host unit to interrupt the CPU as shown in Step 5-2 of FIG. 5, and the interrupted CPU is shown in the block diagram of FIG. The user can search for the status of the connected port registers, send a 'warning message' to the LCD display device as shown in Step 5-3 of FIG. 5, and recognize that the power is off. Stored on an FDD or IC card, which is a storage device (detecting the 'near voltage' for the power required to store it) and then the battery Allow to recharge.

The following describes the operation of LCD output device. A flowchart of this is shown in FIG.

As mentioned above, high signal is output from the 'PB1' terminal of the processor unit to turn off the backlight of the LCD in order to reduce power consumption when there is no input from the keyboard which is an input device for a predetermined time. First, the PMSC detects whether a key is pressed or not for a predetermined time, i.e., every 5 minutes (step 6-2).

If there is no key input during this time, a high signal is output from the PB1 terminal of the processor section in the PMSC to turn off the backlight of the LCD (step 6-3).

Even in this state, the PMSC detects whether a key is pressed, and turns on the backlight (step 6-4) if there is a key input within 2 minutes according to the present embodiment after the backlight is turned off, or otherwise turns off the VDD supplied to the LCD. (See Figure 2.)

However, the computer is still in operation, and only the output device is turned off, so it continuously searches for the key input state and, if there is a key input, supplies the LCD with power for VDD and backlight, and continuously searches for key input. (Step 6-6 to Step 6-9).

Thus, as the device and the control method of the present invention provide, the battery charging and discharging can be efficiently controlled and the battery power state can be visually searched at all times, and the battery charging time is notified. Can be used safely In addition, the power supply is efficiently operated to the output device LCD during use, so it is excellent in power use.

Claims (15)

A laptop computer comprising a host unit 1 having a CPU, a memory device, and an accessory circuit, an LCD output device, a rechargeable battery power supply device, and a key input device, the power consumption of the battery being: In order to control the output device and the charge / discharge battery, the PMSC 4 comprising peripheral device control circuits and a process unit between the host unit 1 and the power supply and the output device, and a port register connected between the PMSC and the host unit, Power supply control device for a laptop computer, characterized in that configured to include (5). The peripheral device control circuit of claim 1, wherein the peripheral control circuit of the PMSC includes an adapter sensing circuit, a battery voltage search circuit, a battery fast charging circuit, a low battery voltage display circuit in relation to a power supply, and an LCD in relation to an output device. A power supply control device for a laptop computer, comprising a power supply voltage control circuit, a VLCD voltage control circuit of an LCD, an LCD backlight control circuit, and a micro switch control circuit. 3. The power supply control device of a laptop computer according to claim 2, wherein the adapter voltage sensing circuit is connected to supply the voltage divider resistors R1 and R2 in series to supply to the input terminal PD1 of the processor unit. 3. The power supply control device for a laptop computer according to claim 2, wherein the battery voltage search circuit is composed of a voltage divider (R5, R6) and an OP amplifier (OP1) as a buffer. The battery fast charging circuit of claim 2, wherein the battery fast charging circuit is connected to the transistor Q21 through resistors R9 and R10 at the output terminal of the processor unit, and an adapter voltage is connected to the collector of the transistor Q21. A power supply control device for a laptop computer, characterized in that the battery is supplied to the battery through a Q20 and an emitter of the transistor Q21 is connected to an LED indicating charging and a temperature sensor TS sensing a temperature of the battery. The laptop battery according to claim 2, wherein the low battery voltage display circuit is configured such that a 'PB2' output terminal of the processor unit is connected to the inverter IN1, and its output is connected to blink an LED connected to one side of the transistor Q23. Power supply control of the computer. 3. The LCD of claim 2, wherein the power supply voltage control circuit of the LCD includes resistors R13-R15 and switching transistors Q31 and Q32. The LCD power supply voltage control turns on the transistor based on the PB7 output voltage level of the processor unit at 1.18. A laptop computer power supply control device, characterized in that the connection is configured to be controlled off. The VLCD power supply control circuit of claim 2, wherein an inverter (IN2), a resistor (R16), transistors (Q34), and (Q34) are connected to the PB1 output terminal of the processor unit, and the VLCD input is inputted by the high / low of the PB1. The power supply control device of a laptop computer, characterized in that the connection is configured to be supplied / blocked via the transistor (Q35). The power supply control device of a laptop computer according to claim 8, wherein each of the high / low levels of the PB1 is 2V or more / 0.8V or less. The backlight control circuit of claim 2, wherein the backlight control circuit of the LCD includes a switching transistor Q33 connected to the voltage regulator and the adjustment terminal Adj of the regulator and receiving the PB6 signal of the processor unit, and an output voltage adjusting resistor connected to the collector of the transistor. Ra, Rb) power supply control device for a laptop computer, characterized in that consisting of. 3. The micro-switch control circuit according to claim 2, wherein the micro switch control circuit has a debounce resistor (R40) and a capacitor (C40) on one side of a switch (μ-S) connected to the power supply to turn off the power when the panel of the laptop computer is closed during power-on. Power supply control device for a laptop computer, characterized in that connected to the PD7 input terminal of the processor. In the control method of the laptop computer power supply control device, the processor unit compares the voltage detected from the battery voltage search circuit and the internal reference voltage set to determine the normal operation or charging, and during charging, the CPU of the host is a warning message The PMSC determines whether the adapter is installed through the alarm sound, the LED blinking, and the adapter voltage sensing circuit, and rapidly charges the battery through the battery quick charging circuit when the adapter is installed and retrieves the charged voltage value. Power supply control method for a laptop computer, characterized in that consisting of. The method of claim 12, wherein the battery voltage is searched at least three times to determine a charging time near a reference voltage value. A method of controlling the power supply of an LCD output device, comprising: turning off the backlight of the LCD when there is no input from the input device for a predetermined time, and then interrupting the VDD supply of the LCD when there is no key input within the predetermined time And supplying an LCD driving voltage in sequence when there is a key input or a key input during the step. 15. The method of claim 14, wherein the predetermined time period is 5 minutes and 2 minutes, respectively.

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