Memory card and data processing system

• US 20050041509A1
• Filed: 07/15/2004
• Published: 02/24/2005
• Est. Priority Date: 08/07/2003
• Status: Active Grant

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Renesas Technology Corporation (Renesas Electronics Corporation)
• Inventors: Hakamura, Yasuhiro, Shikata, Atsushi, Kasai, Hideo, Kumahara, Chiaki, Odate, Hidefumi
• Granted Patent: US 6,982,919 B2
• Time in Patent Office: Days
• US Class Current: 365/226
• CPC Class Codes: G11C 16/30 Power supply circuits

Abstract

A memory card and a microcomputer with nonvolatile memory wherein operation under two different types of power supply specifications is achieved are provided. A MultiMediaCard comprises a flash memory and a controller which controls the operation associated with the flash memory. When the controller judges the level of supply voltage supplied from host equipment, it operates as follows: the controller judges whether detecting point corresponding to the voltage level of 1.8V system has been exceeded. After the judgment of excess, the controller judges whether detecting point corresponding to the voltage level of 3.3V system has been exceeded. When the supply voltage is at the voltage level of 1.8V system, the controller causes the flash memory to operate in the 1.8V-system operation mode without driving regulators or level shifters. When the supply voltage is at the voltage level of 3.3V system, the controller drives the regulators and the level shifters to convert the voltage level and causes the flash memory to operate in the 3.3V-system operation mode.

Claims

1. A memory card comprising:

a nonvolatile memory;

a controller which controls the operation associated with said nonvolatile memory; and

a converter which converts the voltage level in correspondence with the operation of said nonvolatile memory,

wherein first operation mode in which said nonvolatile memory is operated at a first voltage level and second operation mode in which said nonvolatile memory is operated at a second voltage level higher than said first voltage level are provided, and

wherein when said controller judges the level of supply voltage, said controller operates as follows;

said controller judges whether a first detecting point corresponding to said first voltage level has been exceeded;

after the judgment of excess, said controller judges whether a second detecting point corresponding to said second voltage level has been exceeded;

when the supply voltage is at said first voltage level, said controller causes said nonvolatile memory to operate in said first operation mode without driving said converter; and

when the supply voltage is at said second voltage level, said controller drives said converter to convert the voltage level and causes said nonvolatile memory to operate in said second operation mode.

2. The memory card according to claim 1,

wherein said controller has information indicating that the memory card is operable at either or both of said first voltage level and said second voltage level.

3. The memory card according to claim 1,

wherein said controller automatically carries out transition from said first operation mode to said second operation mode and disables transition from said second operation mode to said first operation mode.

4. The memory card according to claim 1,

wherein said controller automatically carries out transition from said first operation mode to said second operation mode and enables transition from said second operation mode to said first operation mode when said controller receives a transition instruction from host equipment.

5. The memory card according to claim 1,

wherein 1.8V system is taken for said first voltage level, and 3.3V system is taken for said second voltage level.

6. A microcomputer with nonvolatile memory comprising:

a nonvolatile memory;

a microcomputer which controls the operation associated with said nonvolatile memory; and

a converter which convert the voltage level in correspondence with the operation of said nonvolatile memory,

wherein first operation mode in which said nonvolatile memory is operated at a first voltage level and second operation mode in which said nonvolatile memory is operated at a second voltage level higher than said first voltage level are provided, and

wherein when said microcomputer judges the level of supply voltage, said microcomputer operates as follows;

said microcomputer judges whether a first detecting point corresponding to said first voltage level has been exceeded;

after the judgment of excess, said microcomputer judges whether a second detecting point corresponding to said second voltage level has been exceeded;

when the supply voltage is at said first voltage level, said microcomputer causes said nonvolatile memory to operate in said first operation mode without driving said converter; and

when the supply voltage is at said second voltage level, said microcomputer drives said converter to convert the voltage level and causes said nonvolatile memory to operate in said second operation mode.

7. The microcomputer with nonvolatile memory according to claim 6,

wherein said microcomputer has information indicating the microcomputer with nonvolatile memory is operable at either or both of said first voltage level and said second voltage level.

8. The microcomputer with nonvolatile memory according to claim 6,

wherein said microcomputer automatically carries out transition from said first operation mode to said second operation mode and transition from said second operation mode to said first operation mode.

9. The microcomputer with nonvolatile memory according to claim 6,

wherein 1.8V system is taken for said first voltage level, and 3.3V system is taken for said second voltage level.