Title:
【発明の名称】携帯情報端末の電池残量監視方式
Document Type and Number:
Japanese Patent JP3070833
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To lead a multitask OS(operating system) to a portable information terminal simply without providing a special mode only for a residual battery amount monitoring. SOLUTION: A residual battery amount monitoring task 21 is operated at every specific time, and it issues a voltage measuring request 17, while a bus hold control circuit 4 issues a bus hold request to a CPU 2 depending on the voltage measuring request 17, and it receives a bus hold request understanding. A voltage measuring start timer 5 outputs a voltage measuring trigger after a specific time, more than the time from receiving the bus hold request understanding to the time the consuming power of the CPU 2 is made to a prescribed value, has passed, so as to report the measuring finish. An A/D converter 6 measures the voltage of a lithium ion battery 1 by receiving the voltage measuring trigger, and outputs the result. The bus hold control circuit 4 makes a bus 10 release the hole by receiving the report of the measuring finish. The residual battery amount monitoring task 21 inputs the measured result and estimates the residual battery amount.
Inventors:
Yoshikazu Ikegami
Application Number:
JP30566796A
Publication Date:
July 31, 2000
Filing Date:
October 31, 1996
Export Citation:
Assignee:
NEC
International Classes:
G01R31/36; G06F1/28; G06F15/02; H01M10/42; (IPC1-7): G06F1/28; G01R31/36; G06F15/02; H01M10/42
Domestic Patent References:
| JP683495A | ||||
| JP7143674A | ||||
| JP8126216A | ||||
| JP8154345A |
Attorney, Agent or Firm:
Junichi Kawahara