U.S. patent application number 09/736193 was filed with the patent office on 2001-06-21 for battery gauging device during battery charging.
This patent application is currently assigned to LG Electronics, Inc.. Invention is credited to Park, Woo Seog.
Application Number | 20010004202 09/736193 |
Document ID | / |
Family ID | 19627037 |
Filed Date | 2001-06-21 |
United States Patent
Application |
20010004202 |
Kind Code |
A1 |
Park, Woo Seog |
June 21, 2001 |
Battery gauging device during battery charging
Abstract
Disclosed is a battery gauging device during a battery charging,
which is capable of gauging the charged capacity during a battery
charging in a terminal. The device according to the invention
comprises a charger for converting an AC voltage to a DC voltage,
and outputting the converted voltage, a battery pack including a
battery for charging an electric charge, first switching means for
switching on/off the DC voltage, and second switching means
switched on/off in accordance with a battery charge enable (BCE)
signal so as to temporarily discharge the charged capacity during
the battery charging, and a terminal including a battery gauging
section for gauging a charged capacity inputted from the battery
pack and a microprocessor for outputting the BCE signal to the
switching means, and displaying the gauged value on a display
section. According to the invention, the DC voltage inputted from
the charger to the battery pack is charged in the battery, but is
regularly interrupted in the course of the battery charging so as
to temporarily discharge the charged capacity, thereby realizing an
exact display of the charged capacity on the terminal even during
the battery charging.
Inventors: |
Park, Woo Seog;
(Kyounggi-do, KR) |
Correspondence
Address: |
FLESHNER & KIM, LLP
P.O. Box 221200
Chantilly
VA
20153-1200
US
|
Assignee: |
LG Electronics, Inc.
|
Family ID: |
19627037 |
Appl. No.: |
09/736193 |
Filed: |
December 15, 2000 |
Current U.S.
Class: |
320/132 |
Current CPC
Class: |
H02J 7/0048 20200101;
H02J 7/0047 20130101 |
Class at
Publication: |
320/132 |
International
Class: |
H02J 007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 18, 1999 |
KR |
59084/1999 |
Claims
What is claimed is:
1. A battery gauging device during a battery charging, comprising:
a charger for converting an AC voltage to a DC voltage, and
outputting the converted voltage; a battery pack including a
battery for charging an electric charge, first switching means for
switching on/off the DC voltage, and second switching means
switched on/off in accordance with a battery charge enable (BCE)
signal so as to temporarily discharge the charged capacity during
the battery charging; and a terminal including a battery gauging
section for gauging a charged capacity inputted from the battery
pack and a microprocessor for outputting the BCE signal to the
switching means, and displaying the gauged value on a display
section.
2. The battery gauging device of claim 1, wherein the battery pack
further includes: a charging/discharging controller for controlling
charging and discharging of the battery and protecting a circuit
inside thereof by controlling the switching on/off of the first
switching means so as to control supply of the DC voltage inputted
from the charger to the battery; and temperature detection means
connected to a ground terminal of the battery for detecting
temperature of the battery, converting the detected temperature
value to an electric signal, and outputting the converted electric
signal.
3. The battery gauging device of claim 1, wherein the terminal
further includes a system electric power section for supplying an
electric power to constitutional elements inside thereof by
receiving an output voltage of the battery pack, and outputting a
voltage for battery gauging to the battery gauging section.
4. The battery gauging device of claim 1, wherein the first and the
second switching means are field effect transistors.
5. The battery gauging device of claim 1, wherein the second
switching means is positioned between the first switching means and
a positive terminal of the battery.
6. The battery gauging device of claim 1, wherein the
microprocessor controls the second switching means by regularly
outputting the BCE signal to the second switching means while a
predetermined voltage is charged in the battery by means of the
charger.
7. The battery gauging device of claim 6, wherein the BCE signal
regularly outputted from the microprocessor has a cycle, in which a
switching-on time is longer than a switching-off time of the second
switching means.
8. The battery gauging device of claim 1, wherein the output
voltage of the battery pack inputted to the terminal is selected
from either the DC voltage inputted from the charger to the battery
pack when the first and the second switching means are switched on
or the discharged capacity of the battery when the second switching
means is switched off.
9. The battery gauging device of claim 1, wherein the battery
gauging section converts the charged capacity of the battery
inputted from the battery pack to a digital signal, and outputs the
converted digital signal to the microprocessor.
10. The battery gauging device of claim 1, wherein the terminal
receives the charged capacity of the battery, and detects the
charged capacity.
11. The battery gauging device of claim 1, wherein the terminal is
a portable terminal using chargable batteries.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a battery gauging device,
and in particular, to a battery gauging device, which can exactly
display on a terminal the charged capacity of a chargable battery
in the course of charging.
[0003] 2. Description of the Prior Art
[0004] FIG. 1 is a block diagram illustrating the conventional
battery gauging device in a mobile telecommunication terminal
during a battery charging.
[0005] Referring to FIG. 1, the conventional battery gauging device
in a mobile telecommunication terminal during a battery charging
comprises: a charger 101 for converting a received alternate
current (AC) to a direct current (DC), and controlling the charging
and discharging of a battery 102a; a battery pack 102 for receiving
the DC, and charging an electric charge into the battery 102a; and
a mobile telecommunication terminal 103 for receiving an output
voltage BAT+ of the battery pack 102, and displaying the charged
capacity of the battery 102a by measuring the voltage BAT+ of the
battery 102a.
[0006] Here, the battery pack 102 comprises: the battery 102a for
charging the electric charge; a charging/discharging controller
102b for controlling charging and discharging of the battery 102a,
and protecting a circuit; and a switch 102c for switching on or off
the DC inputted to the battery 102a under a control by the
charging/discharging controller 102b.
[0007] The mobile telecommunication terminal 103 comprises: a
system electric power section 103a for receiving the DC voltage
BAT+ outputted from the battery pack 102, and supplying the power
of the system; a battery gauging section 103b for converting a
level of the DC voltage BAT+ to a digital signal; and a mobile
station modem 103c as a microprocessor for receiving the digital
signal from the battery gauging section 103b, and displaying the
capacity of the battery 102a on the display section 103c.
[0008] A thermistor 102d is connected to a ground terminal of the
battery 102a, which converts the temperature of the battery 102a to
an electric signal, to control charging and discharging of the
battery 102a in accordance with the temperature. The charger 101
detects a voltage TH of the thermistor 102d, and checks the
temperature of the battery 102a to control the charging and
discharging of the battery 102 in accordance with the
temperature.
[0009] The following is a brief explanation of an operation of the
battery gauging device during a battery charging of a mobile
telecommunication terminal having the above construction.
[0010] Once inputted to the charger 101, the AC is converted to the
DC of a proper level required to charge the battery pack 102, and
outputted. The DC is applied to the battery 102 through the switch
102c so as to charge the battery 102a.
[0011] The charging/discharging controller 102b are connected to
the positive terminal + and a negative terminal to detect the
voltage of the battery 102a, and interrupts charging by switching
off the switch 102c when the voltage of the battery 102a reaches a
predetermined value.
[0012] The charging/discharging controller 102b plays a role of
preventing an excessive charge of the battery 102a above a
predetermined voltage as well as of preventing an excessive
discharge below a predetermined voltage. The charging/discharging
controller 102 also plays a role of preventing an excessive current
due to a short as well as protecting a circuit by preventing
charging under the temperature higher than a predetermined one.
[0013] The DC inputted from the charger 101 to the battery pack 102
charges the battery 102a, and supplies an electric power to the
terminal 103 while the charged voltage becomes an output voltage
BAT+ of the battery pack 102 and is inputted to the terminal 103
for charging.
[0014] To be specific, the voltage of the battery 102a is not
inputted to the terminal 103 during the charging. Instead, the DC
voltage inputted from the charger 101 to the battery pack 102 is
inputted to the terminal 103.
[0015] If the output voltage BAT+ of the battery pack 102 is
inputted to the terminal 103, it is detected by the MSM 103c, which
subsequently transmits a "switch-on" signal to the electric power
section 103a of the system so as to receive the output voltage BAT+
of the battery pack 102 and supply a power to the terminal 103.
[0016] At this stage, the battery gauging section 103b receives the
voltage BAT+ inputted from the terminal 103 from the system
electric power section 103a, and converts the voltage level to a
digital signal for transmission to the MSM 103c. Then, the MSM 103c
displays a capacity of the battery 102a through the display section
103d in accordance with the transmitted digital signal.
[0017] As described above, however, the DC inputted to the battery
pack 102 from the charger 101 charges the battery 102a, and at the
same time, the output voltage BAT+ is inputted to the terminal 103
so that the voltage of the battery 102a may not be inputted to the
terminal 103 during the charging but that the DC voltage inputted
from the charger 101 to the battery pack 102 can be inputted to the
terminal.
[0018] Thus, the output voltage BAT+ of the battery pack 102, which
has been received from the system electric power section 103a by
the battery gauging section 103b of the terminal 103 is not a
voltage from the battery 102a but the voltage from the charger 101.
Therefore, the charged capacity of the battery 102 displayed on the
display section 103d is always indicated to be full.
[0019] As described above, the conventional battery gauging device
during a battery charging has a drawback of failing to display a
capacity of the battery because of inability to measure voltage of
the battery 102a since the DC voltage inputted from the charger 101
is inputted directly to the power supply of the terminal 103 during
the battery charging.
SUMMARY OF THE INVENTION
[0020] It is, therefore, an object of the present invention to
provide a battery gauging device during a battery charging, which
can exactly display the charged capacity of a battery even in the
course of a battery charging by regularly interrupting the voltage
inputted to the battery and measuring the voltage of the battery at
that time during the charging.
[0021] To achieve the above object, there is provided a battery
gauging device during a battery charging according to the present
invention, comprising: a charger for converting an AC voltage to a
DC voltage, and outputting the converted voltage; a battery pack
including a battery for charging an electric charge, first
switching means for switching on/off the DC voltage, and second
switching means being switched on/off by a battery charge enable
(BCE) signal so as to temporarily discharging the charged capacity
during the battery charging; and a terminal including a battery
gauging section for gauging charged capacity inputted from the
battery pack, and a microprocessor for outputting the BCE signal to
the switching means, and displaying the gauged value to the display
section.
[0022] Preferably, the battery pack includes a charging/discharging
controller for controlling charging and discharging of the battery
and protecting an internal circuit by controlling switch on/off of
the first switching means so as to control supply of the DC voltage
inputted from the charger to the battery; and temperature detection
means connected to a ground terminal of the battery for detecting
temperature of the battery, and converting the temperature value to
an electric signal for output of the same.
[0023] Preferably, the terminal includes a system electric power
section for receiving an output voltage of the battery pack from
the terminal, and supplying a power to constitutional elements
inside thereof, and outputting a voltage for battery gauging to the
battery gauging section.
[0024] Preferably, the first and the second switching means are
field effect transistors (FET).
[0025] More preferably, the second switching means is positioned
between the first switching means and positive terminal of the
battery.
[0026] According to the present invention constructed above, the
charged capacity of a battery can be exactly read and displayed on
the terminal even during the battery charging.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The above and other objects, features and advantages of the
present invention will become more apparent from the following
detailed description when taken in conjunction with the
accompanying drawings, in which:
[0028] FIG. 1 is a block diagram illustrating the conventional
battery gauging device in a mobile telecommunication terminal
during a battery charging;
[0029] FIG. 2 is a block diagram illustrating a battery gauging
device in a mobile telecommunication terminal during a battery
charging according to the present invention; and
[0030] FIG. 3 is a timing chart illustrating a timing of a BCE
signal for controlling the second transistor of the battery gauging
device in a mobile telecommunication terminal according to the
present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] A preferred embodiment of the present invention will be
described herein below with reference to the accompanying drawings.
In the following description, well-known functions or constructions
are not described in detail since they would obscure the invention
in unnecessary detail.
[0032] FIG. 2 is a block diagram illustrating a battery gauging
device in a mobile telecommunication terminal during a battery
charging according to the present invention. Referring to FIG. 2,
the battery gauging device during a battery charging according to
the present invention comprises: a charger 201 for converting an AC
voltage to a DC voltage for output of the converted voltage; a
battery 202a for charging an electric charge; a
charging/discharging controller 202b for controlling charging and
discharging of the battery 202a, and protecting a circuit; a
battery pack 202 including a first transistor 201 for switching
on/off the DC voltage inputted from the charger 201 to the battery
202a under a control by the charging/discharging controller 202b,
and a second transistor 202e for temporarily interrupting the DC
voltage inputted to the battery 202a so as to measure voltage of
the battery 202a by means of a BCE signal; and a terminal 203 for
generating the BCE signal for controlling the second transistor
202e, and displaying the charged capacity of the battery by
measuring an output voltage BAT+ of the battery pack 202.
[0033] Preferably, the terminal 203 includes a system electric
power section 203a for supplying a power to the system by receiving
the output voltage BAT+ of the battery pack 202, a battery gauging
section 203b for converting the output voltage BAT+ of the battery
pack 202 to a digital signal, and an MSM 203c as a microprocessor
for displaying the charged capacity of the battery on the display
section 203d by receiving the digital signal from the battery
gauging section 203b.
[0034] A thermistor 202d is connected to a ground terminal GND of
the battery 202a, which converts the temperature of the battery
202a to an electric signal, to control charging and discharging of
the battery 202a in accordance with the temperature. The charger
201 detects a voltage TH of the thermistor 202d, and checks the
temperature of the battery 202a to control the charging and
discharging of the battery 202 in accordance with the
temperature.
[0035] Preferably, the embodiment of the present invention uses an
FET as switching means, which has a fast switching velocity and a
superior resistance to noise.
[0036] The following is a detailed description of an operation of
the battery gauging device during a battery charging in a mobile
telecommunication terminal according to the present invention.
[0037] The charger 201 converts an inputted AC voltage to a DC
voltage of a level required for charging, and outputs the converted
voltage to the battery pack 202. The battery pack 202 receives the
DC voltage so as to be charged in the battery 202 provided inside
thereof.
[0038] The charging process is as follows. The DC voltage inputted
to the battery pack 202 is charged to the battery 202a through the
first transistor 202c and the second transistor 202e connected
thereto, and through a loop provided for the battery 202a.
[0039] At this stage, the charging/discharging controller 202b
detects the charged voltage of the battery 202a by being connected
to the positive terminal + and the negative terminal -, and
switches off the first transistor 202c if the charged voltage
reaches a certain value. When the first transistor 202c is switched
off, the DC voltage is not supplied to the battery 202a, thereby
impeding the charging operation.
[0040] Here, the charging/discharging controller 202b plays a role
of protecting the circuit such as preventing an excessive charging
of the battery 202a above a certain voltage level and an excessive
discharging of the battery 202a below a certain voltage as well as
an excessive current caused by a short and a charging above a
certain temperature.
[0041] Meanwhile, the DC voltage inputted from the charger 201 to
the battery pack 202 is charged to the battery 202a, and becomes an
output voltage BAT+ of the battery pack 202 so as to be inputted to
the terminal 203.
[0042] The terminal 203 is supplied an electric power at the output
voltage BAT+ of the battery pack 202 during the charging. The MSM
203c inside of the terminal 203 detects the electric power supply,
and transmits a switch-on signal to the system electric power
section 203a.
[0043] The system electric power section 203a then receives the
inputted output voltage BAT+ of the battery pack 202, and supplies
a necessary electric power to the terminal 203.
[0044] At this stage, the terminal 203 can measure the battery
voltage by measuring the output voltage BAT+ of the battery pack
203. Here, the measured voltage is not the charged voltage of the
battery 202a but the DC voltage inputted to the battery pack
202.
[0045] To be specific, the charged voltage of the battery 202a
during the charging is not inputted to the terminal 203. Instead,
the DC voltage inputted to the battery pack 202 is inputted to the
terminal 203. Therefore, the actually charged voltage of the
battery 202a cannot be measured by measuring the output voltage
BAT+ of the battery pack 202.
[0046] Therefore, the charged voltage of the battery 202a is
inputted to the terminal 203 as the output voltage BAT+ of the
battery pack 202 by interrupting the DC voltage charging the
battery 202a, and discharging the charged voltage of the battery
202a.
[0047] For that purpose, the MSM 203c regularly outputs the BCE
signal to the battery pack 202 so as to control the output voltage
BAT+ of the battery pack 202.
[0048] The BCE signal inputted to the battery pack 202 is inputted
to a gate terminal of the second transistor 202e to control switch
on/off of the second transistor 202e, thereby regularly
interrupting the DC voltage inputted to the battery 202a from the
charger 201.
[0049] To be specific, when the BCE signal inputted to the battery
pack 202 is in a Low state, the second transistor 202e is switched
on. As a consequence, the DC voltage inputted from the charger 202
is supplied to the battery 202a to charge the battery 202a, and
outputted as the output voltage BAT+ of the battery pack 202.
[0050] When the BCE signal is in a High state, the second
transistor 202e is switched off. As a consequence, the DC voltage
is temporarily interrupted, and the output voltage BAT+ of the
battery pack 202 becomes a charged capacity of the battery 202a
caused by a discharge of the battery 202a.
[0051] Preferably, the BCE signal is a signal having a cycle, in
which the time for discharging and gauging the battery 202a is
shorter than the time for charging the battery 202a for an
effective charge of the battery 202a, as shown in FIG. 3.
[0052] As described above, the DC voltage inputted from the charger
201 becomes the output voltage BAT+ of the battery pack 202 if the
MSM 203c outputs the BCE in a Low state. By contrast, if the MSM
203c outputs the BCE in a High state, the DC voltage is interrupted
by the second transistor 202e, and the discharged voltage of the
battery 202a becomes the output voltage BAT+.
[0053] The battery gauging section 203b receives the voltage BAT+
inputted to the terminal 203 when the BCE signal is in a High state
under a control by the MSM 203c, and converts the corresponding
voltage level to a digital signal for output to the MSM 203c.
[0054] Then, the MSM 203c exactly displays the currently charged
capacity of the battery 202a on the display section 203d in
accordance with the digital signal inputted from the battery
gauging section 203b.
[0055] Thus, the charged capacity of a battery can be exactly
displayed even in the course of the battery charging by temporarily
interrupting the voltage applied to the battery 202a from the
charger 201 and discharging the battery 202a as well as by
measuring the current voltage of the battery 202a.
[0056] The following is a detailed description of a gauging
operation of a mobile telecommunication terminal according to an
embodiment of the present invention.
[0057] The gauging operation of the battery 202a, which is
performed under the power-on state of the terminal 203, can be
classified into two: the gauging operation during the battery
charging under connection of the battery 202a to the charger 201;
and the gauging operation during an operation of the terminal 203
performed by the battery pack 202 under disconnection of the
battery 202a from the charger 201.
[0058] The gauging operation during the battery charging under
connection of the battery 202a to the charger 201 will be explained
first. The charged capacity of the battery 202a is discharged due
to non-appliance of the charged voltage from the
charging/discharging controller 202b to the battery pack 202
despite the connection of the battery pack 202 to the charger 201.
Thus, the discharged capacity of the battery 202a is inputted to
the terminal 203 as the output voltage BAT+.
[0059] In this process, the battery gauging section 203b gauges the
battery voltage, and transfers the gauged level to the MSM 203c in
a digital signal. The MSM 203c then displays the charged state of
the battery 202a on the display section 203d.
[0060] The gauging operation during the battery charging under
disconnection of the battery 202a from the charger 201 will now be
explained.
[0061] The MSM 203c switches off the second transistor 202e with
the BCE signal in a High state for the period of time required for
gauging the battery 202a. As a consequence, the charged voltage of
the battery 202a is discharged, and the discharged voltage is
detected by the system electric power section 202a of the terminal
203 connected to the positive terminal + of the battery 202a. The
battery gauging section 202b then gauges the detected voltage.
[0062] At this stage, the battery gauging section 203b converts the
gauged voltage of the battery to a digital signal, and outputs the
converted digital signal to the MSM 203c. The MSM 203c then
displays a level value corresponding to the digital signal on the
display section 203c.
[0063] Although the embodiment of the present invention exemplified
a mobile telecommunication terminal, the present invention is also
applicable to diverse kinds of portable terminals using chargable
batteries.
[0064] As described above, the battery gauging device according to
the present invention is capable of exactly displaying the charged
capacity of a battery even during the battery charging by
temporarily interrupting the voltage applied to a battery pack from
the charger for charging, discharging the battery, and by measuring
the output voltage of the battery pack during the discharging.
[0065] While the invention has been shown and described with
reference to a certain preferred embodiment thereof, it will be
understood by those skilled in the art that various changes in form
and details may be made therein without departing from the spirit
and scope of the invention as defined by the appended claims.
* * * * *