Apparatus for preventing a malfunction

• US 20070052393A1
• Filed: 12/29/2005
• Published: 03/08/2007
• Est. Priority Date: 09/08/2005
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Okayama, Shigeyuki
• Application Number:
  US11/319,728
• Publication Number:
  US 20070052393A1
• Time in Patent Office: Days
• US Class Current: 320/132
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence

Abstract

A apparatus for preventing a malfunction prevents a malfunction during recovery from critical suspend. The apparatus includes: a voltage detection unit 2 detecting a voltage value from a secondary battery 1; a charging time monitor unit 4 outputting a system activation enable signal when a charging time of the secondary battery 1 by a AC adapter 3 is monitored and a predetermined time passes; and a power supply control unit 5 controlling a system power supply according to a voltage value detected by the voltage detection unit 2 and a system activation enable signal generated by the charging time monitor unit 4.

Claims

1. An apparatus for preventing a malfunction, comprising:

a charging time monitor unit measuring a charging time of a battery in an operation stop status of an electronic equipment due to a low voltage detection on the battery; and

a power supply control unit supplying power to a system in the case where a remaining amount of battery of the battery is equal to or more than a predetermined remaining amount of battery, and in the case where a charge measuring time exceeds a predetermined time.

2. The apparatus according to claim 1, wherein the charging time monitor unit outputs a system activation enable signal in the case where the charge measuring time of the battery exceeds a predetermined time, and the power supply control unit supplies power to a system in the case where a remaining amount of battery of the battery is equal to or more than a predetermined remaining amount of battery and in the case where the system activation enable signal is detected.

3. The apparatus according to claim 1, further comprising:

a voltage detection unit detecting a voltage value of the battery; and

a characteristic table indicating a relationship between a voltage value of the battery and a remaining amount of battery, wherein the power supply control unit refers to the characteristic table, and acquires a remaining amount of battery at a voltage detected by the voltage detection unit.

4. The apparatus according to claim 1, wherein

the charging time monitor unit comprises:

a detection unit continuing outputting a detection signal until the electronic equipment is recovered after the operation stop status is detected from a voltage value of the battery;

a charge detection unit outputting a charge detection signal in the case of detecting charge of a battery by an AC adapter; and

an AC adapter charging time monitor unit outputting a system activation enable signal if the operation stop status is detected in the case where counting is performed up to a predetermined time while the charge detection signal is input.

5. The apparatus according to claim 4, further comprising:

a stable voltage detection unit receiving a voltage of the battery and a predetermined reference voltage, and generating a voltage stable signal in the case where the voltage of the battery is equal to or higher than the predetermined reference voltage; and

a notification unit notifying that a system can be activated in the case of simultaneously detecting a voltage stable signal generated by the stable voltage detection unit and a system activation enable signal generated by the AC adapter charging time monitor unit, and notifying that the system cannot be activated in the case where at least one of the signals is not detected.

6. The apparatus according to claim 4, wherein

the AC adapter charging time monitor unit is a counter circuit starting counting in the case where the charge detection signal is input, and comprises:

a counter circuit generating a count completion notification signal in the case where a predetermined time passes; and

a gate circuit executing a logical sum between a count completion notification signal from the counter circuit and the detection signal and generating the system activation enable signal.

7. The apparatus according to claim 6, wherein

the detection unit is a comparator receiving a voltage of the battery and a predetermined reference voltage, and comprises a comparator generating a detection signal in the case where a voltage of the battery is equal to or lower than a reference voltage.

8. The apparatus according to claim 7, wherein

the AC adapter charging time monitor unit operates by power supply from the AC adapter.

9. The apparatus according to claim 5, wherein

the notification unit comprises:

a gate circuit performing a logical sum between a voltage stable signal generated by the stable voltage detection unit and a system activation enable signal generated by the AC adapter charging time monitor unit; and

an indicator connected to an output terminal of the gate circuit and lighted, and turned off in the case where the voltage stable signal and the system activation enable signal are input to the gate circuit and a high level signal is output.

15. The apparatus according to claim 5, wherein the AC adapter charging time monitor unit is a counter circuit starting counting in the case where the charge detection signal is input, and comprises:

a counter circuit generating a count completion notification signal in the case where a predetermined time passes; and

a gate circuit executing a logical sum between a count completion notification signal from the counter circuit and the detection signal and generating the system activation enable signal.

10. A apparatus for preventing a malfunction, comprising:

a stable voltage detection unit receiving a voltage of the battery and a predetermined reference voltage, and generating a voltage stable signal in the case where the voltage of the battery is equal to or higher than the predetermined reference voltage;

a detection unit outputting a detection signal in the case of a operation stop status of electronic equipment due to low voltage detection of a battery from a voltage value of the battery;

a charge detection unit outputting a charge detection signal in the case where charge of a battery by an AC adapter is detected;

an AC adapter charging time monitor unit counting up to a predetermined time while the charge detection signal is input, and outputting a system activation enable signal in the case where the detection signal is detected;

a notification unit notifying that a system can be activated in the case of simultaneously detecting a voltage stable signal generated by the stable voltage detection unit and a system activation enable signal generated by the AC adapter charging time monitor unit, and notifying that the system cannot be activated in the case where at least one of the signals is not detected.

11. The apparatus according to claim 10, wherein

the AC adapter charging time monitor unit is a counter circuit starting counting in the case where the charge detection signal is input, and comprises:

a counter circuit generating a count completion notification signal in the case where a predetermined time passes; and

a gate circuit executing a logical sum between a count completion notification signal from the counter circuit and the detection signal and generating the system activation enable signal.

12. The apparatus according to claim 11, wherein the detection unit is a comparator receiving a voltage of the battery and a predetermined reference voltage, and comprises a comparator generating a detection signal in the case where a voltage of the battery is equal to or lower than a reference voltage.

13. The apparatus according to claim 12, wherein the notification unit comprises:

a gate circuit performing a logical sum between a voltage stable signal generated by the stable voltage detection unit and a system activation enable signal generated by the AC adapter charging time monitor unit; and

an indicator connected to an output terminal of the gate circuit and lighted, and turned off in the case where the voltage stable signal and the system activation enable signal are input to the gate circuit and a high level signal is output.

14. A method for preventing a malfunction for electronic equipment for use with a power supply control device, comprising:

measuring a charging time of a battery in an operation stop status of electronic equipment due to a low voltage detection on the battery; and

supplying power to a system in the case where a remaining amount of battery of the battery is equal to or more than a predetermined remaining amount of battery, and in the case where a charge measuring time exceeds a predetermined time.