Dynamic memory management

Abstract

In a method, system and apparatus for management of dynamic memory in battery-powered devices, information is stored in dynamic memory, such as SDRAM chips. Chip partitioning minimizes the number of chips requiring power, minimum refresh rates reduce the power needed to maintain information, and a threshold for determining when to power down a battery powered device are used to maximize battery life.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to the field of dynamic memory management. In particular, the present invention relates to hardware and software methods to manage the use of dynamic memory in devices requiring low power consumption, such as battery-powered devices.[0003]2. Description of Related Art[0004]Battery-powered electronic devices such as digital music players and digital cameras typically require significant information storage capacity, and must maintain information during periods of time when the device is in a powered down state. Current battery-powered electronic devices address these needs with various forms of non-volatile memory, such as solid-state flash memory, hard drives, floppy disks, etc. These memory systems however, typically are either very expensive or require too much power to make them viable for inexpensive battery-powered devices. For example, hard drives and floppy disks are inexpensive on a...

AI Technical Summary

Benefits of technology

"The present invention provides hardware and software solutions to enable battery-powered devices to use non-volatile memory instead of battery-powered memory. This is achieved by reducing the supply voltage and frequency of accesses to the non-volatile memory, and by partitioning the dynamic memory to reduce the number of chips needed. The invention also includes a method for determining the minimum refresh rate to reliably maintain information stored in the non-volatile memory. The invention further provides a device comprising a dynamic memory and a clock signal, where the clock signal is only supplied when needed for a read, write, or refresh cycle. The invention also includes a program to determine the minimum refresh rate for each dynamic memory. The invention further includes a battery that can be recharged and a charge threshold to ensure the battery is always ready for use. Overall, the invention enables battery-powered devices to use non-volatile memory more efficiently and reliably."

Problems solved by technology

Battery-powered electronic devices such as digital music players and digital cameras typically require significant information storage capacity, and must maintain information during periods of time when the device is in a powered down state.

These memory systems however, typically are either very expensive or require too much power to make them viable for inexpensive battery-powered devices.

For example, hard drives and floppy disks are inexpensive on a cost per megabyte basis, but are both bulky and require large amounts of power.

Flash memory is expensive, but is compact and reliable.

Volatile memory has not been considered a viable solution because of the high power consumption rate typically associated with the need for constant power to maintain information reliably.

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