Apparatus for controlling LCD backlight in mobile station

• US 7,301,522 B2
• Filed: 02/05/2003
• Issued: 11/27/2007
• Est. Priority Date: 08/28/2002
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Ko, Moon-Jung
• Primary Examiner(s): Hjerpe; Richard
• Assistant Examiner(s): Said; Mansour M.
• Application Number:
  US10/358,876
• Publication Number:
  US 20040041780A1
• Time in Patent Office: 1,756 Days
• Field of Search: 345 82- 84, 345 87- 88, 345 89-102, 345211-212, 345/214, 345/104, 713/300, 713/310, 455/574, 315/169.3
• US Class Current: 345/102
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2330/022 in absence of operation, e.g. no data being entered during a predetermined time
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: H04W 52/027 by controlling a display operation or backlight unit
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

There is provided an apparatus for controlling an LCD backlight in a mobile station to perform the operation of the mobile station in a dimming mode more effectively, and extend the maximum allowable operation time of the mobile station, the apparatus including a backlight LED (light emit diode) for generating a backlight to an LCD, a backlight drive for receiving an input current to supply the input current to the backlight LED to drive, a current control unit for controlling the input current of the backlight drive by a current control signal, and a control unit for supplying the current control signal to the current control unit to control the input current of the backlight drive during operation of the LCD according to a normal mode/dimming mode as predetermined.

Claims

1. An apparatus for controlling a backlight of an LCD in a mobile station comprising:

a backlight LED (Light Emit Diode) for generating a backlight to the LCD;

a backlight drive which receives an input current and supplies an output current to the backlight LED to drive the backlight LED;

a current control unit for controlling the input current of the backlight drive by a current control signal; and

a control unit for supplying the current control signal to the current control unit to control the input current of the backlight drive according to the normal mode or dimming mode, as determined depending on whether there is a user'"'"'s key manipulation, during operation of the LCD,

wherein when in the dimming mode the input current of the backlight drive is less than the input current during the normal mode and greater than 0.

2. The apparatus of claim 1, wherein the current control unit comprises a switch which is switched on or off according to the current control signal, and resistors for forming an input current value of the backlight drive by varying resistance depending on the on and off state of the switch.

3. The apparatus of claim 1, wherein in the normal mode is set during the initial operation of the LCD, the dimming mode is entered into if there is no key input during a predetermined time during the normal mode, and the normal mode is reset if there is a key input during the dimming mode.

4. The apparatus of claim 2, wherein in the normal mode is set during the initial operation of the LCD, the dimming mode is entered into if there is no key input during a predetermined time during the normal mode, and the normal mode is reset if there is a key input during the dimming mode.

5. An apparatus for controlling a backlight in a mobile station including a backlight drive which receives an input current, and supplies an output current to a backlight LED to drive the backlight LED, comprising:

a current control unit including a switch which is switched on and off according to a current control signal, and resistors for forming an input current value of the backlight drive by varying the resistance depending on the on and off state of the switch; and

a control unit for supplying the current control signal to the current control unit to control the input current of the backlight drive during the operation of the LCD according to a normal mode or dimming mode,

wherein when in the dimming mode the input current of the backlight drive is less than the input current during the normal mode and greater than 0.

6. The apparatus of claim 5, wherein the normal mode is set during the initial operation of the LCD, the dimming mode is entered into if there is no key input during a predetermined time during the normal mode, and the normal mode is reset if there is a key input during the dimming mode.