Wireless optical pointing apparatus using battery and method of detecting time for change/recharge of battery thereof

• US 7,884,575 B2
• Filed: 05/30/2007
• Issued: 02/08/2011
• Est. Priority Date: 07/24/2006
• Status: Expired due to Fees

• Current Assignee: ATLab, Inc.
• Original Assignee: ATLab, Inc.
• Inventors: Shin, Young-Ho, Lee, Bang-Won
• Primary Examiner(s): Tso; Edward
• Assistant Examiner(s): WILLIAMS, ARUN C
• Application Number:
  US11/755,525
• Publication Number:
  US 20080018306A1
• Time in Patent Office: 1,350 Days
• Field of Search: 320/132
• US Class Current: 320/132
• CPC Class Codes: G01R 15/04 Voltage dividers
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36

Abstract

Provided are an apparatus using a battery and a method of detecting a time to change/recharge the battery in the apparatus. The apparatus includes: a battery for applying a battery voltage; a function unit for receiving the battery voltage to perform an intrinsic operation and cutting off the battery voltage; a voltage divider for dividing the battery voltage to generate a divided voltage; an analog-to-digital converter (ADC) for receiving the battery voltage to convert the divided voltage into a digital voltage signal in response to a measurement control signal before and after a low-power mode is finished; and a controller for receiving the battery voltage to generate a low-power signal for entering the low-power mode, enabling the measurement control signal in response to the low-power signal before and after the low-power mode is finished, and informing a user of a time to change/recharge the battery by detecting the remaining power of the battery using the digital voltage signals generated before and after the low-power mode is finished.

Claims

1. A wireless optical pointing apparatus comprising:

a battery for applying a battery voltage;

a light source for receiving the battery voltage to generate light;

a battery voltage detector for receiving the battery voltage, detecting the battery voltage in response to a low-power signal which indicates a first power mode in which the light source is turned on to generate a first signal, and detecting the battery voltage in response to the low-power signal which indicates a second power mode in which the light source is turned off to generate a second signal; and

a controller for generating the low-power signal for distinguishing the first power mode from the second power mode, and generating a detection signal for indicating a time to change/recharge the battery by comparing a value obtained using a difference between the first and second signals with a set value,

wherein

the set value is a digital voltage signal corresponding to a difference between a first reference battery voltage and a second reference battery voltage,

the first reference battery voltage is obtained by subtracting a product of an internal resistance of the battery and a current consumed in the optical pointing apparatus during the first power mode from EMF of the battery, and

the second reference battery voltage is obtained by subtracting a product of the internal resistance of the battery and a current consumed in the optical pointing apparatus during the second power mode from the EMF of the battery.

2. The apparatus according to claim 1, wherein the controller generates the low-power signal depending on whether the light source operates or not.

3. The apparatus according to claim 1, wherein the battery voltage detector comprises:

a voltage divider for dividing the battery voltage to generate a divided voltage in each of the first and second power modes; and

an analog-to-digital converter (ADC) for converting the divided voltage into a digital signal to generate each of the first and second signals.

4. The apparatus according to claim 1, further comprising a wireless transceiver for transceiving data wirelessly,

wherein the detection signal is externally transmitted through the wireless transceiver.

5. The apparatus according to claim 1, further comprising a display unit,

wherein information corresponding to the detection signal is displayed on the display unit.

6. A method of detecting a time to change/recharge a battery of a wireless optical pointing apparatus comprising the battery for applying a battery voltage and a light source for receiving the battery voltage to generate light, the method comprising:

detecting the battery voltage to generate a first signal in a first power mode in which the light source is turned on;

detecting the battery voltage to generate a second signal in a second power mode in which the light source is turned off; and

detecting a time to change/recharge the battery by comparing a value obtained using a difference between the first and second signals with a set value,

wherein

the set value is a digital voltage signal corresponding to a difference between a first reference battery voltage and a second reference battery voltage,

the first reference voltage is obtained by subtracting a product of an internal resistance of the battery and a current consumed in the optical pointing device during the first power mode from EMF of the battery, and

the second reference voltage is obtained by subtracting a product of the internal resistance of the battery and a current consumed in the optical pointing apparatus during the second power mode from the EMF of the battery.

7. The method according to claim 6, wherein the first signal is generated by dividing the battery voltage to generate a divided voltage, and converting the divided voltage into a digital signal.

8. The method according to claim 6, wherein the second signal is generated by dividing the battery voltage to generate a divided voltage, and converting the divided voltage into a digital signal.