KR19990055491A - Control method of back light power supply to CDM terminal - Google Patents

Abstract

The present invention relates to a method for controlling the power supply of a backlight in a digital mobile phone which automatically recognizes day and night and cuts off the power supply to the backlight during the day, thereby minimizing the power consumption of the battery. A terminal having a back light display device and a power supply device for supplying power to the display device, the terminal configured to store data stored in a monthly or daily sunrise time and a sunset time, each of which is set from a base station of a corresponding area. Receiving a GPS (Global Position System) time every time or manually setting the current time by the user, and if it is determined that the user is operating the terminal for transmission or reception, the current time is stored using the stored data. Determining whether it is day or night, and wherein the current time is day If it is determined by the steps of: when only a cut off the power from the power supply to be supplied to the display device, the current time is determined as a night set time a step of supplying power to the display device.

Description

Control Method of Power Supply of Backlight in CDMA Terminal

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of controlling power supply of a backlight in a code division multiple access (CDMA) terminal. In particular, during a daytime, a back light that provides background lighting in other words is automatically turned off and attached to a mobile phone. The present invention relates to a method for controlling power supply of a backlight in a CDMA terminal which is suitable for minimizing battery consumption.

As the number of subscribers of digital mobile phones continues to increase due to the rapid development of communication field, the size and lifespan of batteries supplying digital mobile phones is very important. Because the development direction of the mobile phone is proceeding in the light and small size, the appearance of the mobile phone must be increased by that much to increase the capacity of the battery. Therefore, in the industry, the trend is to standardize two types of batteries (medium (900 A) and large (1350 A) for the compatibility of the battery of the cell phone produced by each manufacturer.

Therefore, efforts have been made to increase the capacity of existing batteries and to develop small and powerful batteries using new devices, and efforts have been made to minimize the power consumption of batteries as much as possible.

2 is a control flowchart illustrating a control operation for supplying power to a backlight in a conventional digital cellular phone.

Referring to Figure 2, the control operation for supplying power to the backlight in the conventional digital mobile phone is as follows.

First, when the terminal user selects a power on / off switch provided in the terminal to create a power on state, the CPU provided in the terminal detects this and creates a reception standby state 210. Next, the CPU determines whether keypads such as the numbers “0” to “9”, “SEND”, and “END” of the key panel 122 are selected (220). If no pad is selected, the mobile phone returns to the reception standby state 210 after a set time, and if it is determined that a random keypad is selected, the backlight for the backlight of the liquid crystal display of the mobile phone is always present. It is determined whether it is set to be in an off state (230), and if it is always set to be in an off state, the backlight is continuously turned off (240).

However, if the backlight is not set to be always off in the determining step 230, it is determined whether the backlight is set to be turned on only for a set time (eg, 10 seconds) (250), If it is set to be turned on, the CPU controls to turn off the backlight after the set time (260). However, if it is not set to turn on only for the time set in the determination process 250, the backlight is continuously turned on.

However, in practice, the user of the terminal is set to turn on the backlight for both day and night whenever any keypad is selected due to the ease of use, and the above-described operation is an option for the user who wants to save power. To provide.

Therefore, while providing a great convenience in the use of the terminal at night, it is unnecessary power consumption during the day. Of course, the terminal user can set the backlight unit to be turned on twice a day, that is, during the day and at night, so that the backlight unit is not turned on during the day and the backlight is turned on only at night. There is a possibility that confusion may occur.

For reference, once the backlight is turned on, it consumes about 10mA of current, and this unnecessary power is a big burden for people who travel many places a day and make a lot of calls.

Disclosure of the Invention An object of the present invention is to solve the problems described in the prior art, and automatically recognizes day and night to cut off the power supply to the backlight during the day, thereby minimizing the power consumption of the battery. To provide a power supply control method of the.

In order to achieve the above object, the present invention comprises at least one display device for the back light (light), and a power supply for supplying power to the display device, each month or daily sunrise time and A terminal in which data is stored as a time, the method comprising receiving a GPS (Global Position System) time or setting a current time manually by a base station of a corresponding area, and a user transmitting or receiving the terminal. Determining whether the current time is day or night by using the stored data, and when the current time is determined to be daytime, cutting off the power supplied from the power supply to the display device. And when the current time is determined to be night, the display device only for a set time. It consists of supplying power.

1 is a plan view showing the appearance of a typical digital mobile phone.

Figure 2 is a control flow diagram showing a control operation for supplying power to the backlight in the conventional digital mobile phone.

3 is a control flow diagram illustrating a control operation for supplying power to a backlight in a digital cellular phone according to the present invention.

4 is a circuit diagram for supplying power to a backlight according to the prior art and the present invention.

<Description of the symbols for the main parts of the drawings>

100: terminal body 110: liquid crystal display device

111: LED for backlight 120: Key pad

121: LED backlight for the keypad 130: Antenna

140: receiver 150: transmitter

BCT: Backlight Control Terminal R1: Resistance

L1-L8: LED Q1: Transistor

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The appearance of the digital cellular phone according to the present invention is the same as the conventional cellular phone shown in FIG. That is, a liquid crystal display (LED) 110 in the mobile phone main body 100, a backlight LED 111 of the LCD, a number (0 to 9) included in the key panel 122, Key pad 120 indicating characters (SEND, END, POWER, ON / OFF) and symbols (#, *), LED backlight 121, antenna 130, receiver 140, microphone of keypad It includes a transmitting device 150 such as. In the present embodiment, the number of the backlight LED 111 and the backlight LED 121 of the keypad is set to four and eight, respectively, but the number and location of the backlight LED 111 may vary to some extent during the design of the product. .

3 is a control flowchart illustrating a control operation for supplying power to a backlight in a digital cellular phone according to the present invention.

Referring to Figure 3, the control operation for supplying power to the backlight in the digital mobile phone according to the present invention is as follows. First, when the terminal user selects the power on / off switch provided in the terminal to create a "power on" state 300, the CPU provided inside the terminal senses this and creates a reception standby state 310. Then, the CPU determines whether the GPS (Global Position System) time is received from the base station in the corresponding area (320), and if the GPS time is not received every set period from the base station returns to the reception standby state (310). However, if the CPU receives the GPS time from the base station, it is determined whether the current time is AM (330), and if the current time is AM, it is determined whether the user has manually turned on the backlight (350). In this case, the memory device of the terminal stores the average time from January to December and the time of decay in advance, or the user inputs the current time manually so that the CPU of the terminal can distinguish between day and night. .

If it is determined in step 350 that the backlight is turned on manually, the backlight is turned on manually (360), otherwise the backlight is automatically turned on (370). If the current time is not AM in the determination step 330, it is recognized that the current time is night or a dark place such as a basement, and the CPU determines whether there is an operation of the keypad of the key panel 122 (340). If the pad has not been operated, the process returns to the input terminal of the determination step 330. However, if there was an operation of the keypad, it is determined whether there is a selection of the "SEBD" key among the keypads (380), and if the selection of the "SEND" key has been selected, the CPU assumes that the user has started transmitting and receiving to the cellular phone. (I.e., since the backlight is unnecessary at this time), the backlight is immediately controlled to be large (390). However, if no "SEND" key has been selected, the CPU assumes that the other party's telephone number has not yet been selected or is operating another function and controls the backlight to increase after a set time such as 10 seconds (391). ).

FIG. 4 is a circuit diagram for supplying power to a backlight according to the related art and the present invention, and the backlight control shown in FIG. 4 by a control signal (eg, an electrical high level signal) for the CPU of the terminal to turn on the backlight. When applied to the terminal BCT, this high level signal is supplied to the base terminal of the switching transistor Q1, and eventually the transistor Q1 is conducted. At this time, the power terminal Vcc and the ground terminal G are connected to the resistor R1. By adjusting the voltage difference, the backlight LED of the LCD and the backlight LED of the keypad can be illuminated by the voltage difference.

In FIG. 4, as an example, eight LEDs L1-L8 are illustrated as the backlight LED 121 of the keypad.

Such a power control method according to the present invention can be applied to cellular phones using about 800MHz band or PCS phones using 1.8GHz.

According to the present invention, the terminal receiving the GPS time from the base station or the user can set the current time to determine whether the current day and night, the daytime of the backlight LED to the keypad of the liquid crystal display device provided to the terminal Automatically cut off the power supply of the backlight LED.

Claims (5)

A terminal comprising at least one display device for back light and a power supply device for supplying power to the display device, wherein the terminal stores data for each month or daily sunrise time and sunset time by data. Receiving a GPS (Global Position System) time from the base station in the area or the user manually set the current time, Determining whether the current time is day or night by using the stored data when it is determined that the user is operating the terminal for transmission or reception operation; If the current time is determined to be daytime, cutting off the power supplied to the display device from the power supply device; And supplying power to the display device only for a predetermined time when the current time is determined to be nighttime. The method of claim 1, wherein the display device is at least one light emission diode (LED) for a backlight. The method of claim 1, wherein the power supply device is a battery. The terminal of claim 1, wherein the terminal is one of a code division multiple access (CDMA) terminal, a cellular terminal using a frequency band of about 800 MHz, and a PCS terminal using a frequency band of about 1.8 GHz. The power supply control method of the backlight in the terminal, characterized in that. The power supply of the backlight of the terminal according to claim 1, wherein when the current time is determined to be night and the power is supplied, when the " SEND " key provided in the terminal is selected, the power supply is cut off from the battery. Control method.