Back to results
US 8,044,815 B2Granted
Systems and methods for battery status indication
AssigneeO2Micro, Inc.
InventorsSterling Du, Liusheng Liu, Oleksandr Kokorin
Life of this patent
Estimating the term…
Abstract
A method and apparatus are provided to indicate battery capacity status. Different blinking frequencies of an LED correspond to different battery states of charge. Furthermore, the present invention provides a smooth visual brightness change of the LED by providing the appropriate LED current according to human eye characteristics.
Claims19
A method for charge storage component status indication, comprising:
- determining the state of charge of said charge storing component;
- generating a pulse width modulated signal based on said state of charge, said pulse width modulated signal having pulses that have widths modulated to cause periodic exponential increases and decreases in an average current flowing in at least one LED, wherein said pulses comprise a first plurality of consecutive pulses having durations that increase over time and a second plurality of consecutive pulses having durations that decrease over time, wherein said average current is exponentially increased in response to said first plurality of consecutive pulses and is exponentially decreased in response to said second plurality of consecutive pulses;
- and
- providing said pulse width modulated signal to said at least one LED, wherein said average current has a frequency that causes a brightness of said LED to increase and decrease such that said LED blinks at a predetermined blinking frequency.
1 more element
An indicator controller for indicating a status of a charge storage component, comprising:
- a pulse width modulator for generating a pulse width modulated (PWM) signal based on a feedback signal that is representative of a status of said charge storage component, said pulse width modulated signal having pulses that have widths modulated to cause periodic exponential increases and decreases in an average current flowing in at least one LED, wherein said pulses comprise a first plurality of consecutive pulses having durations that increase over time and a second plurality of consecutive pulses having durations that decrease over time, wherein said average current is exponentially increased in response to said first plurality of consecutive pulses and is exponentially decreased in response to said second plurality of consecutive pulses, wherein said average current has a frequency that causes a brightness of said LED to increase and decrease such that said LED blinks at a predetermined blinking frequency, and wherein said pulse width modulator is capable of using different blinking frequencies to indicate different statuses of said charge storage component by adjusting said blinking frequency according to the feedback signal.
A battery status indicator system, comprising:
- a battery monitor coupled to a battery for determining battery status and providing a feedback signal representative of said battery status;
- at least one LED receiving an average current;
- and
- an indicator controller coupled to said battery monitor for providing a pulse width modulated (PWM) signal representative of said average current flowing through said at least one LED, and adjusting the pulse width of said PWM signal to produce said average current in a periodic exponential form, wherein said PWM signal comprises a first plurality of consecutive pulses having durations that increase over time and a second plurality of consecutive pulses having durations that decrease over time, said average current is exponentially increased in response to said first plurality of consecutive pulses and is exponentially decreased in response to said second plurality of consecutive pulses, said average current having a frequency representative of a blinking frequency of said at least one LED, said controller further capable of using different blinking frequencies to indicate different battery statuses by adjusting said blinking frequency according to said feedback signal.
1 more element
Dependencies are inferred from the claim text.