Battery power measuring system and method for a battery-backed SRAM
First Claim
1. A battery power measuring system for a Battery-Backed SRAM (Static Random Access Memory), comprising:
- a nonvolatile memory for storing a system time, an estimated battery maximal endurance, an estimated battery minimal endurance, and a cumulative on-battery run time;
a clock for indicating a current system time;
a CPU (Central Processing Unit) for calculating a new cumulative on-battery run time based on a former system time, the estimated battery maximal endurance and a former cumulative on-battery run time, and for calculating a remaining battery endurance according to the estimate battery maximal endurance and the new cumulative on-battery run time; and
a buzzer for reminding one or more users to replace a battery when the remaining battery endurance is lower than the estimated battery minimal endurance.
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Accused Products
Abstract
A battery power measuring system for a Battery-Backed SRAM includes a nonvolatile memory (11), a clock (12), a CPU (10) and a buzzer (13). The nonvolatile memory is for storing a system time, an estimated battery maximal endurance, an estimated battery minimal endurance, and a cumulative on-battery run time. The clock is for indicating the current system time. The CPU is for calculating a new cumulative on-battery run time and a remaining battery endurance. The buzzer is for reminding users to replace a battery when the remaining battery endurance is lower than the estimated battery minimal endurance. The CPU is connected to the nonvolatile memory, the clock, and the buzzer through a plurality of data buses (14). A related battery power measuring method is also provided.
18 Citations
13 Claims
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1. A battery power measuring system for a Battery-Backed SRAM (Static Random Access Memory), comprising:
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a nonvolatile memory for storing a system time, an estimated battery maximal endurance, an estimated battery minimal endurance, and a cumulative on-battery run time; a clock for indicating a current system time; a CPU (Central Processing Unit) for calculating a new cumulative on-battery run time based on a former system time, the estimated battery maximal endurance and a former cumulative on-battery run time, and for calculating a remaining battery endurance according to the estimate battery maximal endurance and the new cumulative on-battery run time; and a buzzer for reminding one or more users to replace a battery when the remaining battery endurance is lower than the estimated battery minimal endurance. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A battery power measuring method for a Battery-Backed SRAM, comprising the steps of:
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providing a nonvolatile memory for storing a system time, an estimated battery maximal endurance, an estimated battery minimal endurance and a cumulative on-battery run time; providing a clock for indicating a current system time; calculating a new cumulative on-battery run time according to a former system time, a former cumulative on-battery run time, and the current system time; calculating a remaining battery endurance according to the estimated battery maximal endurance and the new cumulative on-battery run time; determining whether the remaining battery endurance is lower than the estimated battery minimal endurance; providing a buzzer and triggering the buzzer to remind one or more users to replace the battery if the remaining battery endurance is lower than the estimated battery minimal endurance; storing the current system time in the nonvolatile memory; determining whether a primary power source is unavailable; and storing the current system time in the nonvolatile memory if the primary power source is available and still powering. - View Dependent Claims (9, 10, 11, 12)
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13. A battery power measuring method for a Battery-Backed SRAM, comprising the steps of:
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providing a nonvolatile memory for storing a system time, an estimated battery maximal endurance, an estimated battery minimal endurance and a cumulative on-battery run time; providing a clock for indicating a current system time; calculating a new cumulative on-battery run time according to a formula;
the new cumulative on-battery run time=a former cumulative on-battery run time+a current system time−
a former system time;calculating a remaining battery endurance according to a formula;
the remaining battery endurance=the estimated battery maximal endurance−
the new cumulative on-battery run time; andsending a warning signal if the remaining battery endurance is lower than the estimated battery minimal endurance;
whereinno testing is required through any hardware.
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Specification