Power supply control system with power factor improvement circuits and electronic device equipped with this system
In order to provide a power supply control system for driving power supply units efficiently depending on difference between loads, a power supply control system for controlling power supply operation to supply power to an electronic device having a first drive mode and a second drive mode that is driven under a load lower than a load in the first drive mode includes: power supply units each of which includes transformers; and a PFC switching/power supply unit switching section (power supply unit selection section) that, depending on which one of the first and second drive modes the electronic device is in, selects power supply unit(s) to be used from the power supply units, wherein the PFC switching/power supply unit switching section selects the one or a plurality of power supply units to be used from the plurality of power supply units such that each power supply unit to be used to supply power to the electronic device in the second drive mode is one or some of each power supply unit to be used to supply power to the electronic device in the first drive mode.
1. A power control system for controlling power supply operation to supply power to an electronic device including a first drive mode and a second drive mode that is driven under a load relatively lower than a load in the first drive mode, the power control system comprising:
a plurality of power supply units, each including a transformer; and
a power supply unit selection section to, depending on which one of the first and second drive modes the electronic device is in, select one or a plurality of power supply units to be used from the plurality of power supply units, wherein the power supply unit selection section is configured to select the one or a plurality of power supply units to be used from the plurality of power supply units such that each of the power supply units to be used to supply power to the electronic device in the second drive mode is one or some of each of the power supply units to be used to supply power to the electronic device in the first drive mode;
power-factor improvement circuits, each respective one of the power-factor improvement circuits being included in a respective one of the plurality of power supply units which is useable to supply power to the electronic device in the second drive mode; and
a power-factor improvement circuit control section to, depending on which one of the first and second drive modes the electronic device is in, switch whether to actuate or not actuate the power-factor improvement circuit, wherein the power-factor improvement circuit control section is configured to actuate the power-factor improvement circuit in the first drive mode and is configured to not actuate the power-factor improvement circuit in the second drive mode.
2. The power supply control system according to claim 1 , wherein:
the electronic device is a light source device for a liquid crystal display; and
the first drive mode is a drive mode for a moving image display, and the second drive mode is a drive mode for a still image display.
3. The power supply control system according to claim 2 , wherein:
the light source device has a plurality of divided domains;
in the first drive mode, each power supply unit to be used supplies power to one of the plurality of divided domains; and
in the second mode, a plurality of power supply units to be used cooperate to supply power to all the plurality of divided domains or one of the plurality of power supply units is used to supply power to all the plurality of divided domains.
4. An electronic device, comprising:
a power supply control system according to claim 3 ,
the electronic device having the first mode and the second mode.
5. An electronic device, comprising:
a power supply control system according to claim 2 ,
the electronic device having the first mode and the second mode.
6. An electronic device, comprising:
a power supply control system according to claim 1 ,
the electronic device having the first mode and the second mode.