An intelligent power supply system for a portable computer

Claim 2

A power supply system for a portable computer, the computing having a central processing unit (CPU) (11), and being operable in response to power supplied from at least two rechargeable batteries (341, 342) or an alternating current (AC) adapter, characterised by further comprising: a power control microprocessor (306) for controlling power supply independent of the CPU (11), the microprocessor (306) having means for generating a control signal based on battery select information for controlling the power supply; and battery control circuit means (311), connected to the AC adapter and the batteries (341, 342) for supplying power from the AC adapter or one of the batteries (341, 342) based on the control signal from the power control microprocessor (306).

Claim 3

A power supply system according to claim 1 in which the said batteries are detachable.

Claim 4

A power supply system according to claim 1 or claim 2 characterised in that the portable computer comprises an internal bus (307) for connecting the CPU (11) to the power control microprocessor (306) to transfer the battery select information, and an I/O register (310) provided between the power control microprocessor (306) and the battery control circuit means (311) and used for data transfer therebetween.

Claim 5

A power supply system according to any preceding claim characterised in that the power control microprocessor (306) has means for receiving the battery select information from the CPU (11) via the internal bus (307) and supplying the control signal to the battery control circuit means (311) via the I/O register (310).

Claim 6

A power supply system for a portable computer, the computer having a central processing unit (CPU) (11), and being operable in response to power supplied from at least two rechargeable batteries (341, 342) or an alternating current (AC) adapter, characterised by further comprising: means connected to the CPU (11), for determining whether the AC adapter or one of the batteries (341, 342) is being used as the power-supply; means connected to the AC adapter and the batteries (341, 342), for controlling the battery which is in use as a power supplying batter, based on said determination; means for detecting the charge levels of the batteries (341, 342); and means for selecting that battery which is judged as sufficiently charged, as the power supplying battery.

Claim 7

A power supply system for a portable computer, the computer having a central processing unit (CPU) (11), and being operable in response to power supplied from at least two rechargeable batteries (341, 342) or an alternating current (AC) adapter, characterised by further comprising: means connected to the CPU (11), for determining whether the AC adapter or one of the batteries (341, 342) is being used as the power-supply; means connected to the AC adapter and the batteries (341, 342), for controlling the battery which is in use as a power supplying batter, based on said determination; means for detecting the charge levels of the batteries (341, 342); and means for selecting that battery which is judged as sufficiently charged, as the power supplying battery.

Claim 8

A power supply system according to claim 5, characterised in that the select means comprises: first means for directly selecting a first battery if it is not found to be in a low charge condition by the detecting means; and second means for alternatively selecting the second battery which is not found to be in a low charge condition by the detecting means when the detecting means determines that the first battery (341, 342) is in a low charge condition.

Claim 9

A power supply system according to claim 5 or claim 6 characterised in that the detecting means includes: at least one current detector (312, 314) for measuring values of currents from the batteries (341, 342); and A/C converter means (316) for performing analog-­to-digital conversion of a current value detected by the current detector (312, 314) and supplying a digital output value to the judging means.

Claim 10

A power supply system according to any of claims 5 to 7, characterised in that the portable computer further comprises means for charging the batteries while the computer is operated on power from the AC adapter when the AC adapter is selected as the power supply.

Claim 11

A power supply system according to any of claims 5 to 8 characterised in that the portable computer has means for charging the battery which is sufficiently charged while the other battery serves as a power supply.

Claim 12

A power supply system according to any of claims 5 to 9 characterised in that the portable computer has an additional built in spare battery. In addition to the batteries (341, 342), for supplying driving power to the computer for a specific period of time even when the batteries (341, 342) are detached from the computer.

Claim 13

A power supply system for a portable computer, the computer having a central processing unit (CPU) (11), and being operable in response to power supplied from at least two rechargeable batteries (341, 342) or an alternating current (AC) adapter, characterised by further comprising: a power control microprocessor (306) for supplying a control signal for controlling power supply independent of the CPU (11), the microprocessor (306) having means for determining the status of connection of the AC adapter and charge conditions of the batteries (341, 342); means for selecting the AC adapter or one of the batteries (341, 342) based on the control signal from the power control microprocessor (306) and supplying selected power to the computer; and means for generating an alarm in response to the control signal output from the power control microprocessor (306).

Claim 14

A power supply system for a portable computer, the computer having a central processing unit (CPU) (11), and being operable in response to power supplied from at least two rechargeable batteries (341, 342) or an alternating current (AC) adapter, characterised by further comprising: a power control microprocessor (306) for supplying a control signal for controlling power supply independent of the CPU (11), the microprocessor (306) having means for determining the status of connection of the AC adapter and charge conditions of the batteries (341, 342); means for selecting the AC adapter or one of the batteries (341, 342) based on the control signal from the power control microprocessor (306) and supplying selected power to the computer; and means for generating an alarm in response to the control signal output from the power control microprocessor (306).

Claim 15

A power supply system according to claim 11, characterised in that the determining means includes first means for detecting whether the AC adapter is connected, second means for determining the charge condition of one of the batteries (341, 342), and third means for determining the charge condition of the other battery.

Claim 18

A method according to claim 12, characterised in that the second step includes: a sixth step of selecting the first battery based on battery select information from the CPU (11); a seventh step of judging whether or not the first battery is connected to the computer; and an eighth step of generating an alarm when it is judged in the seventh step that the first battery is not connected to the computer.

Claim 19

A method according to claim 12, characterised in that the third and fifth steps include: a ninth step of determining whether or not the battery is in a low battery status; and a tenth step of generating an alarm when it is determined in the ninth step that the battery is in a low battery status.

Claim 20

A method according to claim 12, characterised by further comprising: an eleventh step of charging the battery which is insufficiently charged when it is judged in the first step that power is supplied from the AC adapter; and a twelfth step of determining whether or not the battery is charged up to a predetermined voltage.