Integrated circuit wake-up control system

Patent metadata

Field	Value
Publication number	US-9252774-B2
Application number	US-201313902872-A
Country	US
Kind code	B2
Filing date	May 27, 2013
Priority date	May 27, 2013
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

An integrated circuit (IC) that operates in high and low power modes includes high and low power regulators, first and second sets of circuits, a switch connecting the high power regulator and the second set of circuits, and a wake-up control system. The wake-up control system includes a state machine that enables the high power regulator when the IC is in the high power mode, and enables the low power regulator when the IC is in the low power mode. The switch is closed when the high power regulator reaches a first threshold voltage. The state machine operates on a low frequency clock signal when the IC is in the low power mode and during wake-up, and on a high frequency clock signal in the high power mode after the switch is closed.

First claim

The invention claimed is:

1. An integrated circuit, comprising:
first and second sets of electronic circuits;
a high power regulator that provides a first regulated supply voltage to the first and second sets of electronic circuits when the integrated circuit is in a high power mode and is switched off when the integrated circuit is in a low power mode;
a low power regulator that provides a second regulated supply voltage to the second set of electronic circuits when the integrated circuit is in the low power mode and is switched off when the integrated circuit is in the high power mode; and
a switch, connected between a first shared point of the high power regulator and the first set of electronic circuits, and a second shared point of the low power regulator and the second set of electronic circuits, for connecting the high power regulator to the second set of electronic circuits when the integrated circuit is in the high power mode, and disconnecting the high power regulator from the second set of electronic circuits, and the low power regulator from the first set of electronic circuits when the integrated circuit is in the low power mode, and when the integrated circuit transitions from the low power mode to the high power mode,
wherein the second set of electronic circuits includes,
a wake-up control system, connected to the high and low power regulators and the switch, and the wake-up control system includes,
a wake-up state machine that enables the high power regulator when the integrated circuit transitions from the low power mode to the high power mode and closes the switch to connect the high power regulator to the second set of electronic circuits when the high power regulator reaches a first threshold voltage, and
wherein the wake-up state machine operates on a low frequency clock signal when the integrated circuit transitions from the low power mode to the high power mode and the switch is open, and operates on a high frequency clock signal having a frequency that is higher than the frequency of the low frequency clock signal when the switch is closed.

2. The integrated circuit of claim 1 , wherein the wake-up control system further comprises a high frequency clock source for generating the high frequency clock signal and a low frequency clock source for generating the low frequency clock signal.

3. The integrated circuit of claim 2 , wherein the wake-up control system further comprises a switch state indicator connected to the switch for indicating whether the switch is open or closed, and connected to the high frequency clock source for enabling the high frequency clock source when the switch is closed.

4. The integrated circuit of claim 3 , wherein the wake-up control system further comprises a clock multiplexer having a first input terminal connected to the low frequency clock source for receiving the low frequency clock signal, a second input terminal connected to the high frequency clock source for receiving the high frequency clock signal, a select terminal connected to the switch state indicator for receiving a current state of the switch, and an output terminal connected to the wake-up state machine, wherein the clock multiplexer provides the low frequency clock signal to the wake-up state machine when the switch is open and provides the high frequency clock signal to the wake-up state machine when the switch is closed.

5. The integrated circuit of claim 4 , wherein the wake-up control system further comprises a wake-up signal generator, connected to the low frequency clock source, for generating a wake-up signal to enable the low frequency clock source when the integrated circuit transitions from the low power mode to the high power mode.

6. The integrated circuit of claim 1 , wherein the wake-up state machine disables the low power regulator when the switch is closed.

7. An integrated circuit (IC), comprising:
first and second sets of circuits;
a high power regulator that provides a first regulated supply voltage to the first and second sets of circuits when the IC is in a high power mode and is switched off when the IC is in a low power mode;
a low power regulator that provides a second regulated supply voltage to the second set of circuits when the IC is in the low power mode and is switched off when the IC is in the high power mode; and
a switch, connected between a first shared point of the high power regulator and the first set of electronic circuits, and a second shared point of the low power regulator and the second set of circuits, for connecting the high power regulator to the second set of circuits when the IC is in the high power mode, and disconnecting the high power regulator from the second set of circuits, and the low power regulator from the first set of electronic circuits when the IC is in the low power mode, and when the integrated circuit transitions from the low power mode to the high power mode,
wherein the second set of circuits includes a wake-up control system connected to the high and low power regulators and the switch, and wherein the wake-up control system includes:
a high frequency clock source for generating a high frequency clock signal and a low frequency clock source for generating a low frequency clock signal having a frequency that is lower than the frequency of the high frequency clock signal;
a switch state indicator, connected to the switch, for indicating whether the switch is open or closed;
a wake-up state machine, that enables the high power regulator when the IC transitions from the low power mode to the high power mode and closes the switch to connect the high power regulator to the second set of circuits when the high power regulator reaches a first threshold voltage, and wherein the wake-up state machine operates on the low frequency clock signal when the IC transitions from the low power mode to the high power mode and the switch is open, and operates on the high frequency clock signal when the switch is closed;
a clock multiplexer having a first input terminal connected to the low frequency clock source for receiving the low frequency clock signal, a second input terminal connected to the high frequency clock source for receiving the high frequency clock signal, a select terminal connected to the switch state indicator for receiving a current state of the switch, and an output terminal connected to the wake-up state machine, wherein the clock multiplexer provides the low frequency clock signal to the wake-up state machine when the switch is open and provides the high frequency clock signal to the wake-up state machine when the switch is closed; and
a wake-up signal generator, connected to the low frequency clock source, for generating a wake-up signal to enable the low frequency clock source when the IC transitions from the low power mode to the high power mode.

8. The IC of claim 7 , wherein the switch state indicator is connected to the high frequency clock source for enabling the high frequency clock source when the switch is closed.

9. The IC of claim 7 , wherein the wake-up state machine disables the low power regulator when the switch is closed.

10. A wake-up control system of an integrated circuit (IC), wherein the IC includes first and second sets of circuits, high and low power regulators, and a switch connected between a first shared point of the high power regulator and the first set of circuits, and a second shared point of the low power regulator and the second set of circuits, and wherein the wake-up control system is connected to the high power regulator, the low power regulator and the switch, the wake-up control system comprising:
a wake-up state machine that opens the switch to disconnect the first set of circuits from t

Assignees

• Gupta Sunny
• Abhishek Kumar
• Pant Nitin
• Sharda Garima
• Freescale Semiconductor Inc

Inventors

• Gupta Sunny
• Abhishek Kumar
• Pant Nitin
• Sharda Garima

Classifications

• G06F1/3287

  by switching off individual functional units in the computer system · CPC title

• G06F1/26

  Power supply means, e.g. regulation thereof (for memories G11C) · CPC title

• G06F1/32

  Means for saving power · CPC title

• H03K19/0016 Primary

  by using a control or a clock signal, e.g. in order to apply power supply · CPC title