This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present invention that are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Due to increased expenses associated with providing energy and a desire to conserve natural resources, legislation and standards are being put in place to encourage improved energy efficiency. One example is the Energy Star Program, which provides standards for power consumption by electronic devices such as televisions and set top boxes. The Energy Star standard specifies requirements for operating modes called “Standby Power” and “Run Mode.” Energy conservation is achieved by reducing or completely removing power from various device subsystems in Standby Power mode relative to Run Mode. Moreover, device systems that are not needed unless the device is being used by a user (“Run Mode”) may be shut down in Standby Mode to conserve power.
In addition to saving power when devices are in Standby Mode, it is also desirable to reduce device power consumption in when operating in Run Mode. However, a number of obstacles make shutting down the operation of device subsystems during Run Mode undesirable. For example, if a user switches from an NTSC analog channel to an external video input like a DVD player, the TV tuner could potentially be turned off to save power because it is not necessary for the TV tuner video input to be processed and displayed on the screen. The drawback to turning off the tuner is that tuners require a relatively long period of time to become operational or “warm up” when power is reapplied. This means that the previously tuned channel will not be immediately available if the user switches back to the NTSC tuner from the DVD player. During the intervening time, the user is undesirably subjected to viewing a “blanked” display. This problem is particularly pronounced with the viewing of digital channels because the process of acquiring a valid “I Frame” on a digital channel may take several seconds, resulting in a much longer “blanked” time that could be annoying to users. An improved system and method for providing reduced power consumption for an electronic device that is being used for normal operation is desirable.