JPH05333973A - Power unit for portable computer - Google Patents

Abstract

PURPOSE:To run the power control section by means of only the power battery without providing an auxiliary power source on the power control section by assuring that the computer is not stopped even when the battery being in use is removed erroneously. CONSTITUTION:The power unit is provided with a power controller 3 controlling the power supply section, discharge switches 2a and 2b one end of which is connected to the power battery and the other end of which is connected to a DC/DC converter 4, and delay section 5 comparing the input voltage of the converter 4 with the reference voltage and outputting the control voltage of the discharge switches 2a and 2b which are turned on until the section 3 completes the operation selecting the normal power batteries 1a and 1b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device for a portable personal computer. A portable personal computer (hereinafter referred to as a computer) can be used with a battery power source in addition to a commercial AC power source. Then, a power supply control unit that sequentially controls turning on / off of power supply to each internal circuit and an attached disk device is provided, and battery remaining amount monitoring, charge / discharge control, disk data protection, and logic circuit Controls such as stable operation and protection against power failure or power failure are performed. And
The control is performed by program control using a microcomputer.

On the other hand, a portable computer is equipped with a plurality of power supply batteries, and usually one of them is selected to drive the computer, and when the supply voltage drops, the power supply control unit selects another power supply battery. I have to.

When a user replaces a battery whose voltage has dropped in the power supply battery having such a structure, the computer may be accidentally driven to remove the discharging battery. In such a case, it is necessary to instantly switch to another power supply battery without stopping the operation of the computer. Further, the power supply control unit has an auxiliary power supply in addition to the power supply battery, and performs the above power supply control by detecting the power-on of the power switch by the user. However, when the voltage of the auxiliary power supply is low, the power supply battery Was unable to start the power supply control unit, and started to use the AC power supply to start the power supply control unit. Therefore, in such a case, the computer could not be used in a place where the AC power supply could not be used.

[0004]

2. Description of the Related Art FIG. 5 shows the configuration of a power supply unit in a conventional portable computer. In FIG. 5, 100 is a portable computer, 101 is a power supply battery, and 102 is DC /
A DC converter 103 is a power supply control unit, which starts the DC / DC converter after the power switch is turned on by the user and controls the charging / discharging of the power supply battery 101. 104 and 105 are contacts A and
The contact B serves to electrically connect the power supply battery 101 to the main body of the computer 100. 106
Is a contact C, which provides the power supply control unit 103 with connection information of the power supply battery that drives the computer 100.

In the figure, when the power supply battery 101 is pulled out, the contact C (106) is first disconnected, and then the contact A (104) and the contact B (105) are disconnected. Has been.

Therefore, when the power supply battery 101 is pulled out,
First, the contact C (106) is removed. At this time, since the power supply battery side of the contact A (104) and the contact B (105) and the computer main body side are electrically connected, the power supply control unit 103 removes the contact C and thus the power supply battery 101 It is detected that the power supply battery has been pulled out, and the connection process between the other power supply battery and the DC / DC converter 102 is performed. Further, by pulling out the power supply battery 101, the contact A (104) and the contact B (105) are removed, and the power supply battery 101 is removed. During that time, the computer 100 is driven by the newly selected power supply battery, so that the operation is not interrupted.

FIG. 6 shows a conventional power supply device. In the figure, 110 is a power supply battery and 111 is an AC / DC converter for converting the AC voltage of a commercial AC power supply into a DC voltage. 112 is a DC / DC converter.
Reference numeral 113 is a discharge switch, and when turned on, the power battery 1
It connects or disconnects 10 and the DC / DC converter 112. 114 is a power switch.
Reference numeral 115 denotes a power supply control unit, which is a discharge switch ON (connects the power supply battery 110 and the DC / DC converter 112) and OFF (power supply battery 110 and the DC / DC converter 1).
12 is disconnected). 11
An auxiliary battery 6 is a battery for starting the power supply control unit 115 and retaining the contents of the memory when the power is off.

In the discharge switch 113, the FET is a field effect transistor, which is turned on or off in response to the operation of the transistor TR which is controlled by the power supply control unit 115 to be turned on or off. TR is a transistor, which is turned on or off under the control of the power supply control unit 115 and controls the FET. R1, R2, R3, R4 are resistors. R5 is a pull-up resistor, and the power switch 11
4 is turned off, the voltage of the terminal B of the power supply control unit 115 is raised to a high level.

The operation of the configuration shown in the figure will be described. [When the voltage of the auxiliary battery is normal] When the power switch 114 is turned on, the power control unit 115 starts operating and outputs a high level signal from the terminal A. As a result, TR
Is turned on, and the power supply battery 110-resistor R1-resistor R2
A current flows in the circuit of -TR-ground electrode, and the FET is turned on due to the voltage difference across the resistor R1. Then, the voltage of the power supply battery 110 is DC / via the FET and the diode D2.
It is applied to the DC converter 112.

The DC / DC converter 112 is the power source battery 1
Power is supplied from 10 to operate, and power is supplied to each unit of the computer and the power supply control unit 115. After that, the power supply control unit 115 operates by being supplied with power from the DC / DC converter 112, keeps the output voltage of the terminal A at a high level, and performs other processing such as charging control of the power supply battery 110.

[When the Voltage of the Auxiliary Battery is Decreasing] Next, the voltage of the auxiliary battery 116 decreases and the power supply control unit 11
The case where 5 does not operate will be described.

The power switch 114 is turned off, the power control unit 115 is reset, the output of the terminal A becomes low level, and the FET is turned off. When the power switch 114 is turned on in this state, the power control unit 115 does not operate because the voltage of the auxiliary battery 116 is low. for that reason,
The output of the terminal A of the power supply control unit 115 remains L and T
R is off. Therefore, the FET is not turned on and DC
The / DC converter 112 does not start operation.

In order to operate the computer in such a case, a commercial AC power source is used, and first, A
The C / DC converter 111 is operated by an AC power source and
The DC / DC converter 112 is operated using the C / DC converter 111 as a power source. Then, the power supply control unit 11
5 operates by the DC / DC converter 112 thus activated.

[0014]

As described above, in the conventional portable computer power supply device, the operation of the computer is interrupted even if the battery in use is accidentally pulled out when the battery that cannot be used is replaced. The guarantee is to ensure that there is an operating sequence due to the mechanical structure of the contact between the battery power supply unit and the computer body, and the power supply control unit switches to another power supply battery when it detects that the battery in use is pulled out. I was doing.

Therefore, the user may not operate normally depending on the speed at which the battery is taken out, and it is difficult to design with high reliability. In addition, the mechanical structure of the power supply unit and the operation sequence of the power supply control unit were complicated.

Further, conventionally, when the voltage of the auxiliary battery of the power supply control unit is lowered, the computer cannot be operated by the power supply battery, and the commercial power supply must be used. Therefore, when the voltage of the auxiliary battery was low, the computer could not be used in a place without commercial power.

The present invention guarantees that the operation of the computer will not stop even if the battery in use is accidentally removed, regardless of the mechanical structure of the power supply unit.
An object of the present invention is to provide a power supply device for a portable computer that can start the operation of a power supply control unit only with a power supply battery without using an auxiliary power supply.

[0018]

According to the present invention, when a power supply battery in use (discharging) is pulled out, a voltage drop due to the pulling out is detected, and a voltage control unit switches to another battery. Until then, the DC / DC converter did not stop operating.

Further, by turning on the power switch, DC / D
Until the C converter operates, the discharge switch is turned on without using the auxiliary battery of the power supply control unit, and the DC / DC converter can be started by the power supply battery.

FIG. 1 shows the basic configuration (1) of the present invention. In the figure, 1a and 1b are power supply batteries, and a power supply control unit 3
One of them is used to discharge. Reference numerals 2a and 2b denote discharge switches, which are controlled to be turned on or off by the output of the power supply control unit 3 or the delay unit 5. Reference numeral 3 is a power supply control unit for controlling on / off of the discharge switches 2a and 2b. 4 is a DC / DC converter.

Reference numeral 5 denotes a delay unit, which is a discharge switch (2
a, 2b), the voltage input to the DC / DC converter 4 is compared with the reference voltage, and when a decrease in the input voltage of the DC / DC converter 4 is detected, at least the power supply controller 3
Until the power battery is switched to the discharge switch 2a,
The control voltage for turning on both 2b is output to each discharge switch. The delay unit 5 is composed of, for example, a time constant circuit. Reference numeral 6 is a comparison unit for comparing the reference voltage with the input voltage of the DC / DC converter 4. Reference numeral 7 is a delay means, which is composed of, for example, a resistor and a capacitor, and outputs a high level voltage for a certain period of time according to its time constant.

The operation of the basic configuration (1) of FIG. 1 will be described later. FIG. 2 shows the basic configuration (2) of the present invention. In the figure, 10 is a power battery, 11 is a power switch, 12 is a discharge switch,
Reference numeral 13 denotes a delay unit (which is the same as the delay unit 5 in FIG. 2. However, in the basic configuration (2), at least a voltage equal to or higher than the lowest voltage at which the DC / DC converter 14 can be operated is set to DC / DC. Output is made until the DC converter 14 starts operation). Reference numeral 13 'is a comparison unit, 13''is a delay means. 14 is a DC / DC converter, and 15 is a power supply control unit.

In the discharge switch 12, FET is a field effect transistor, TR is a transistor, R1, R2,
R3 and R4 are resistors. R5 is a pull-up resistor for pulling up the voltage of the terminal B of the power supply controller 15 to a high level while the power switch 11 is off.

The operation of the configuration of FIG. 2 will be described later.

[0025]

The operation of the basic configuration (1) of the present invention shown in FIG. 1 will be described. It is assumed that the power supply battery 1a is selected, the discharge switch 2a is on, and the discharge switch 2b is off. That is,
It is assumed that the power supply battery 1a is discharged and supplies power to the DC / DC converter 4.

In this state, it is assumed that the power supply battery 1a is pulled out. As a result, the input voltage of the DC / DC converter 4 drops. The comparison unit 6 is the DC / DC converter 4
When it detects that the input voltage of has dropped to the reference voltage,
In the delay unit 7, the power supply control unit 3 connects the power supply battery to the power supply battery 1b.
Until it is switched to, the high-level signal is output by the time constant circuit and both the discharge switches 2a and 2b are turned on. Therefore, the voltage of the power supply battery 1b is applied to the DC / DC converter 4 to maintain the operation. As a result, even if the power battery 1a is pulled out, the DC / DC converter 4 continues to operate and the computer continues to operate.

The operation of the basic configuration (2) of the present invention shown in FIG. 2 will be described. When the power switch is turned off, the power control unit 15 is reset and the FET of the discharge switch 12 is turned off.

When the power switch 11 is turned on, the resistance R
Since one end of 2 becomes the ground potential, the power supply battery 10-resistor R
1-Resistor R2-Current flows in the circuit of the ground electrode, and resistance R2
The FET is turned on by the potential difference between both ends of the. for that reason,
The voltage of the power supply battery 10 is applied to the DC-DC converter 14 to start the operation.

At this time, the comparison unit 13 'of the delay unit 13
Detects that the input voltage of the DC / DC converter 14 is higher than the reference value, the time constant circuit of the delay unit 13 keeps the low level voltage for at least the time until the DC / DC converter 14 starts operating. Output. Therefore, the time for the user to push down the power switch is short, and D
Even if the power switch is turned off before the operation of the C / DC converter 14 is started, the discharge switch 12 continues to be turned on due to the low level voltage output from the delay means 13 ″, and the DC / DC converter 14 Starts to work.

When the DC / DC converter 14 is activated, the power supply control unit 15 starts operating, and the power supply control unit 15 outputs a high level voltage from the terminal A. Therefore, the transistor TR is turned on, current flows through the circuit of the power supply battery 10-resistor R1-resistor R2-TR-ground electrode, and the resistor R1.
The FET is turned on due to the voltage difference. And DC-D
When the power of the power supply 10 is supplied to the C converter 14, DC /
The DC converter 14 continues to operate.

As described above, according to the present invention, the computer can continue to operate normally even if the power supply battery in use is accidentally pulled out. In addition, the computer can be reliably started with only the power battery without using an auxiliary battery for the power controller.

[0032]

Embodiment FIG. 3 shows an embodiment (1) of the present invention. The figure shows a configuration in which a plurality of batteries are mounted and the power supply battery is switched without stopping the operation of the computer when the discharging battery is removed.

In the figure, 30a and 30b are power supply batteries,
31 is a power control unit, 32 is a DC / DC converter, 33
Is a delay unit, and is a time constant circuit (for example, MB3771).
IC). 34 is a comparison unit, 3
Reference numeral 4'denotes a delay circuit which delays the voltage with a resistor and a capacitor and outputs the delayed voltage. 35a,
35b is a discharge switch. 36a and 36b are charge switches, each of which is a DC / DC converter 32.
Are turned on when the power supply batteries 30a and 30b are charged. D1, D1 'are charge current bypass diodes, and D2, D2' are discharge current bypass diodes.

In the discharge switch 35a, FET is a field effect transistor, TR1 is a transistor, R1 and R.
2, R3 and R4 are resistors. Discharge switch circuit 35b
, FET 'is a field effect transistor, TR1'
Is a transistor, and R1 ', R2', R3 ', R4' are resistors.

D3, D3 ', D4 and D5 are diodes. The operation of the configuration shown in the figure will be described. A case where the power supply battery 30a is discharged will be described as an example.

The power supply controller 31 sets the voltage output to the base of the transistor TR1 of the discharge switch 35a to H (high level) to turn on TR1. As a result, a current flows in the circuit of the power supply battery 30a-resistor R1-resistor R2-TR1-ground electrode, and the FET due to the voltage difference across the resistor R1.
Turns on. Therefore, the power supply battery 30a-the FET of the discharge switch 35a-the diode D2-the diode D4-
The DC / DC converter 32 circuit supplies power to the DC / DC converter 32 from the power supply battery 30a.
The converter 32 operates.

On the contrary, when charging the power supply battery 30a from the DC / DC converter 32, the power supply control unit 31 turns on the FET of the charging switch 36a. As a result, DC / D
Current flows from the C converter 32 to the power supply battery 30a through the FET of the charging switch 36a and the diode D1,
The power supply battery 30a is charged (the details of the charging circuit are omitted in the figure).

While the power supply battery 30a is discharging, the power supply battery 30a
The operation when a is extracted will be described. Power battery 30
If a is extracted during discharge, the DC / DC converter 3
The input voltage of 2 drops. The comparison unit 34 is the power supply battery 30a.
DC / D by comparing input voltage from Vref with reference voltage
When it is detected that the input voltage of the C converter 32 has dropped, the delay circuit 34 'outputs a high-level voltage for turning on the transistor 2 for a fixed time (for example, about 1 second).
As a result, during that time (1 second), TR2 is turned on, current flows through the circuit of the power supply battery 30b-R1'-R2'-TR2-ground electrode, and the voltage difference across the resistor R1 'causes
ET 'turns on.

Therefore, even if the power supply battery 30a is removed, the DC / DC converter 32 does not stop operating. During that time, the power supply control unit 31 detects that the power supply battery 30a is removed and turns on the discharge switch 36b. Even if the output of the delay circuit disappears and TR2 is turned off, the FET 'continues to turn on and the DC / DC converter 32
Keeps working.

FIG. 4 shows an embodiment (2) of the present invention. The figure is
This is a configuration for starting the operation of the main power supply DC / DC converter from the battery power supply from a completely uninterrupted state (the power supply control unit DC / DC converter is not operating).

In the figure, reference numerals 40a and 40b denote power supply batteries which are selected by the power supply control unit 45 and which are discharged. 40 'is an AC / DC converter, 4
1 is a power switch, 42a and 42b are discharge switches, 4
2'a is a circuit of a part of the discharge switch 42a. D
Reference numerals 1 and D3 are diodes that bypass the charging current.
43a and 43b are charge switches. D2 and D4 are diodes that bypass the discharge current. Reference numeral 44a is a DC / DC converter for the main power supply, which supplies electric power to the disk device, the printed board unit and the like. 45
Is a power supply control unit, 46 is a delay unit, 47 is a disk device, 4
8 is a Pt plate unit.

The operation of the configuration shown in the figure will be described. Power control unit 4
5 is reset and the discharge switches 42a and 42b are turned off.

When the user turns on the power switch 41,
The discharge switches 42a and 42b are turned on. So D
If the voltage of the power supplies 40a and 40b is applied to the C / DC converter 44b and one of them is perfect, DC / DC
The DC converter 44b starts operating. Then, the power supply control unit 45 operates and the DC / DC converter 44a operates. Then, electric power is supplied to the Pt plate unit 48 and the disk device 47.

At this time, if the power switch is turned off before the operation of the DC / DC converter 44b is started, DC
Since the input voltage of the / DC converter 44b decreases, the delay unit 46 operates and outputs a low level signal for a certain period of time. As a result, the discharge switches 42a and 42b are kept on, and the DC / DC converter 44b is activated during that period. The power supply control unit 45 starts operation.

Then, the power supply control unit 45 selects the power supply battery to be discharged, and the discharge switch (42) for the selected power supply battery is selected.
The output signal of the terminal connected to a, 42b) is turned on. A part of TR1 and TR2 of the discharge switch 42a connected to the output terminal of the high level signal is turned on, and the discharge switch 42a and the discharge switch 42b including the turned-on transistors TR1 and TR2 are turned on. Therefore, from the selected power supply battery (40a, 40b) DC /
Power is continuously supplied to the DC converter 44b, and DC / D
The C converter 44b continues to operate.

[0046]

According to the present invention, when the discharging battery is accidentally removed, the switching of the power supply battery can be performed only by the electric circuit operation, not by the structure of the contact of the power supply unit. Therefore, the structure of the power supply unit can be simplified and the operation sequence of the power supply control unit can be simplified.

Further, the computer can be started by the power supply battery without requiring an auxiliary battery for guaranteeing the operation of the power supply control unit. Therefore, even in a place where commercial power cannot be used, the computer can be reliably started from the completely de-energized state with only the power battery.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration (1) of the present invention.

FIG. 2 is a diagram showing a basic configuration (2) of the present invention.

FIG. 3 is a diagram showing an embodiment (1) of the present invention.

FIG. 4 is a diagram showing an embodiment (2) of the present invention.

FIG. 5 is a diagram showing a configuration of a conventional power supply device.

FIG. 6 is a diagram showing a conventional power supply device.

[Explanation of symbols]

 1a: power supply battery 1b: power supply battery 2a: discharge switch 2b: discharge switch 3: power supply control unit 4: DC / DC converter 5: delay unit 6: comparison unit 7: delay means 10: power supply battery 11: power supply switch 12: discharge Switch 13: Delay unit 13 ': Comparison unit 13 ": Delay unit 14: DC / DC converter FET: Field effect transistor TR: Transistor R1: Resistor R2: Resistor R3: Resistor R4: Resistor R5: Resistor D1: Diode D2: Diode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takashi Shitsuji, Nouki-nu, Heki-gun, Hebei-gun, Ishikawa Prefecture 2 No. 98, No. 2 PIE Co., Ltd. (72) Inventor Toshiaki Toda, Noki, Hebei-gun, Ishikawa Prefecture Noki No. 98 No. 2 Inside PFU Co., Ltd.

Claims (5)

[Claims] 1. A power supply device for a portable computer, comprising: a power supply battery; and a DC / DC converter (4) driven by the power supply battery. A power supply control unit (3) for controlling the power supply device, and a power supply. A discharge switch, which is provided for each battery and has one end connected to the power supply battery and the other end connected to the DC / DC converter (4), compares the input voltage of the DC / DC converter (4) with the reference voltage, When it is detected that the input voltage has dropped, at least until the power supply control unit (3) selects and switches another power supply battery (1a, 1b) different from the discharged power supply battery, each discharge switch (2a, 2b) is provided with a delay unit (5) for outputting a control voltage,
When the input voltage to the C / DC converter (4) drops, each discharge switch is turned on and another power supply battery that is different from the power supply battery that was being discharged automatically without interrupting the operation of the portable computer A power supply device for a portable computer, which has a switching function. 2. A power supply device for a portable computer, comprising a power supply battery (10) and a DC / DC converter (14) driven by the power supply battery, and a power supply control section (15) for controlling the power supply device. , A discharge switch having one end connected to the power battery (10) and the other end connected to a DC / DC converter (14)
(12) When the power switch (11) is turned on, the input voltage of the DC / DC converter (14) is compared with the reference voltage and the discharge is performed at least until the DC / DC converter (14) starts operating. A DC / DC converter (including a delay unit (13) for outputting a control voltage of a discharge switch for turning on the switch (12) is used by the power supply battery (10) even when the drive voltage of the power supply control unit (15) cannot be secured. 14) A power supply device for a portable computer, which is capable of starting up. 3. The power supply device for a portable computer according to claim 1, wherein the delay units (5) and (13) are composed of a time constant circuit. 4. The power supply control unit (3), (15) according to claim 1 or 2, wherein the power supply control unit (3), (15) is not provided with an auxiliary power supply for starting the operation of the power supply control unit (3), (15). Power supply for portable computers. 5. The power supply control unit (3), (15) according to claim 1 or 2, wherein the auxiliary power supply for starting the operation of the power supply control unit (3), (15) is a DC / DC converter. A power supply device for a portable computer, characterized in that