Decentralized power management system for integrated circuit using local power management units that generate control signals based on common data

• US 6,968,467 B2
• Filed: 10/23/2001
• Issued: 11/22/2005
• Est. Priority Date: 10/26/2000
• Status: Expired due to Term

• Current Assignee: Socionext Inc.
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Inoue, Akihiko, Kai, Koji, Hamada, Masao
• Primary Examiner(s): Cao, Chun
• Assistant Examiner(s): WANG, ALBERT C
• Application Number:
  US09/983,296
• Publication Number:
  US 20020053039A1
• Time in Patent Office: 1,491 Days
• Field of Search: 326/80, 365/226, 713/320
• US Class Current: 713/320
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode

Abstract

A power management system for an integrated circuit has a signal line, a management data generating unit connected to the signal line, and a plurality of management data using units each connected to the signal line. The management data generating unit outputs, to the signal line, power management data for managing power consumption in each of the management data using units, the power management data corresponding to the state of the management data generating unit. Each of the management data using units reads the power management data for common use from the signal line and controls power consumed by the management data using unit based on the power management data.

Claims

1. A power management system for an integrated circuit, the system comprising:

a signal line;

a management data generating unit connected to the signal line; and

a plurality of management data using units each connected to the signal line,

wherein the management data generating unit outputs, to the signal line, power management data indicative of a state of at least a part of the power management system,

wherein each of the management data using units reads the power management data for common use from the signal line and controls power consumed by the management data using unit itself utilizing the power management data,

wherein each of the management data using units includes;

a slave block operating as a slave; and

a power management unit corresponding to the slave block, the power management unit reading the power management data from the signal line, generating a control signal for performing power control over the corresponding slave block based on the power management data, and outputting the control signal,

wherein the slave block controls power consumed by the slave block in accordance with the control signal outputted from the corresponding power management unit,

wherein each of the power management units generates the control signal based on the power management data for common use.

2. The power management system of claim 1, wherein the management data generating unit is a master block operating as a master, the master block including:

a data processing circuit for performing data processing; and

a data output unit for outputting the power management data to the signal fine based on a state of the data processing circuit.

3. The power management system of claim 2, wherein the data processing circuit includes:

a boundary scan register for storing data inputted to and outputted from the data processing circuit and outputting the data to the data output unit; and

a register control unit for controlling an operation of the boundary scan register,

wherein the data output unit effects specified control over the register control unit to direct the boundary scan register to store and output the data and determines the state of the data processing circuit based on the data outputted from the boundary scan register.

4. The power management system of claim 1, wherein the management data generating unit includes:

a master block operating as a master; and

a data output unit corresponding to the master block, the data output unit outputting the power management data to the signal line based on a state of the corresponding master block.

5. The power management system of claim 4, wherein the management data generating unit includes a plurality of master blocks, at least two of the plurality of master blocks corresponding in common to one of the data output units.

6. The power management system of claim 1, wherein at least two of the slave blocks correspond in common to one of the power management units.

7. The power management system of claim 1, wherein the power management unit comprises a buffer, the buffer regenerating a signal representing the power management data and outputting the regenerated signal.

8. The power management system of claim 1, wherein the power management unit comprises a flip-flop, the flip-flop latching the power management data and outputting the latched power management data.

9. The power management system of claim 1, wherein the power management unit comprises a data conversion unit for converting the power management data to the control signal.

10. The power management system of claim 9, wherein the data conversion unit is a memory.

11. The power management system of claim 9, wherein the data conversion unit is composed of a logic circuit.

12. The power management system of claim 11, wherein the logic circuit is a programmable device.

13. The power management system of claim 1, further comprising:

a data transmission unit between the signal line and the management data using unit, the data transmission unit reading the power management data from the signal line, selecting data to be transmitted to the management data using unit, and outputting the selected data.

14. The power management system of claim 1, wherein the management data using units are grouped,

the management data generating unit outputs group specifying data in conjunction with the power management data to the signal line, and

each of the management data using units belonging to a group specified by the group specifying data controls power consumed by the management data using unit.

15. The power management system of claim 1 further comprising, in addition to the management data generating unit, at least one management data generating unit, one of the management data generating units outputting, to the signal line, the power management data corresponding to a state of the management data generating unit.