Miscellaneous active electrical nonlinear devices – circuits – and – Specific identifiable device – circuit – or system – With specific source of supply or bias voltage
Reexamination Certificate
1999-10-22
2002-04-09
Le, Dinh T. (Department: 2816)
Miscellaneous active electrical nonlinear devices, circuits, and
Specific identifiable device, circuit, or system
With specific source of supply or bias voltage
C363S095000, C327S143000
Reexamination Certificate
active
06369643
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus and method for controlling a power saving mode of a power supply.
2. Description of the Conventional Art
A conventional apparatus for controlling a power saving mode of a power supply is automatically switched to a power saving mode to minimize the power consumption of a power supply when a power saving mode key input signal is externally applied or a predetermined time has elapsed since alternating current(AC) power was supplied but the loads do not consume the AC power. Also, when the power supply is in the power saving mode, a backup capacitor of a backup unit provides power to a key input signal input unit and a microcomputer of the power saving mode controlling apparatus to detect the power supply operation key input signal.
FIG. 1
is a schematic block diagram illustrating a conventional switching mode power supply (SMPS) developed by the inventors of the subject application and disclosed in application Ser. No. 09/373,075, filed Aug. 11, 1999; and hereby incorporated by reference in its entirety. As shown, the SMPS includes a power supply circuit unit
124
and a controlling unit
122
.
As shown therein, the power supply circuit unit
124
includes an input filter unit
101
receiving AC power from an AC power source and reducing noise included in the AC power; a rectifying and smoothing unit
102
rectifying and smoothing the noise free AC power; a switching device Q
1
receiving a predetermined control signal from first and second signal feedback units
107
and
108
and switching on/off a transformer
104
, which is to be later described; a snubber
103
eliminating switching noises which are generated in accordance with the switching on/off operation of the switching device Q
1
; a transformer
104
receiving DC (direct current) power outputted from the rectifying and smoothing unit
102
and transforming energy from a primary terminal to secondary terminals of the transformer
104
in accordance with an on/off operation of the switching device Q
1
, for thereby inducing a plurality of AC voltages; a first rectifying and smoothing unit
105
inputting the AC voltages which are induced at the secondary terminals of the transformer
104
, rectifying and smoothing the AC voltages and outputting a plurality of DC voltages; a switching unit
109
receiving the DC voltages and outputting DC voltages Vo
1
, Vo
2
, . . . , VoN to loads (not shown) in accordance with the control of a microcomputer
110
; a second rectifying and smoothing unit
105
-
1
inputting AC power, which was generated from an auxiliary terminal of the transformer
104
, and outputting a DC voltage; and a driving control unit
106
receiving the DC voltage outputted from the second rectifying and smoothing unit
105
-
1
and control signals outputted from a control unit, which will be later described, and controlling the switching on/off operation of the switching device Q
1
.
Further, the control unit
122
of the conventional SMPS includes a microcomputer
110
controlling the system based in part on receiving key input signals such as from a power supply button
120
; a timer
111
generating and outputting a timing signal to the microcomputer
110
; a multiplexer
114
supplying either a high or low frequency signal from respective high and low frequency oscillators
116
and
118
to the microcomputer
110
and the timer
111
; a backup unit
112
charged by receiving one of the DC voltages outputted from the rectifying and smoothing unit
105
and supplying power to the microcomputer
110
in the power saving mode; the first signal feedback unit
107
providing DC power to the driving control unit
106
; and the second signal feedback unit
108
controlling an operation of the driving control unit
106
in accordance with a control signal outputted from the microcomputer
110
in the power saving mode. Wherein the first and second signal feedback units
107
and
108
, respectively, are constituted of a photocoupler PC
1
, a switching device Q
2
(e.g., a transistor), and resistors R
3
, R
4
.
The operation of the conventional SMPS will be described in detail with the accompanying drawings.
When it is in a normal mode, where the loads consume power and AC power is inputted to the input filter unit
101
from AC source power, the input filter unit
101
eliminates the noises included in the AC power and outputs the noise free AC power to the rectifying and smoothing unit
102
. Then, the rectifying and smoothing unit
102
rectifies and smoothes the noise free AC power supply and outputs a DC voltage having a predetermined level to a primary terminal of the transformer
104
and the driving control unit
106
.
Here, as the driving control unit
106
switches the switching device Q
1
on and off, a plurality of AC voltages are induced to the secondary terminals of the transformer
104
. Then the rectifying and smoothing unit
105
receives, rectifies and smoothes the induced AC voltages; thereby outputting DC voltages to the switching unit
109
, which outputs the DC voltages Vo
1
, Vo
2
, . . . , VoN to the loads (not shown).
In the above-described normal mode, the microcomputer
110
, which receives one of the DC voltages outputted from the rectifying and smoothing unit
105
, controls the switching unit
109
so that it provides matching power to the loads. During the normal mode, the microcomputer
110
instructs the multiplexer
114
to output the high frequency signal so that the microcomputer
110
operates at the high frequency clock from the timer
111
. Also, the backup unit
112
receives the DC power and charges a backup capacitor C
3
, for providing the charged power to the microcomputer
110
in the power saving mode.
When the power supply is in the normal mode, in which the loads consume the power, and a user inputs a power saving mode key input signal or a predetermined period of no power consumption has elapsed, the microcomputer
110
outputs a control signal having a predetermined duty to a photodiode PD of the photocoupler PC
1
in the second signal feedback unit
108
through a resistor R
2
. When the photodiode PD and a phototransistor PT in the photocoupler PC
1
are operated, the switching device Q
2
outputs a control signal to the driving control unit
106
, and, accordingly, the driving control unit
106
is controlled. Here, when the second signal feedback unit
108
is switched on, the driving control unit
106
receives a ground level signal, thereby stopping the switching operation of the switching device Q
1
and stopping the operation of the transformer
104
. Accordingly, the SMPS enters into a power saving mode.
When the transformer
104
is stopped and no voltages are induced in the secondary terminals of the transformer
104
, that is when the SMPS is in the power saving mode, the backup unit
112
supplies a backup power to the microcomputer
110
. Also, the microcomputer
110
causes the multiplexer
114
to output the low frequency signal so that the microcomputer
110
operates at a low frequency clock signal such as 32 kHz during the time when the transformer
104
does not operate.
When the power supply is in the power saving mode under the above-mentioned conditions, if a power supply operation key input signal is inputted to the power supply via the power supply button
120
, the power supply immediately supplies the power to the loads.
FIG. 2A
illustrates a remote controller (R/C) key input signal supplied to the conventional SMPS. The R/C key input signal includes a full code and a continuous code. The full code consists of a header and data, and the consecutive code indicates that a remote controller key is continuously pressed.
FIG. 2B
illustrates the full code of
FIG. 2A
in detail, wherein a header or enable part is a low frequency signal having a high level D
1
and a low level D
2
for a duration of 9.5 ms and 4.5 ms respectively, and a data or SMPS on part is a high frequency signal having a high level D
3
and a low level D
4
for a duratio
Lee Dong Ju
Pyeon Dae Beum
Birch & Stewart Kolasch & Birch, LLP
Le Dinh T.
LG Electronics Inc.
LandOfFree
Apparatus and method for controlling power saving mode in a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for controlling power saving mode in a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for controlling power saving mode in a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2867142