# US 2021/0278892 A1 · Electronic device and associated control method for reducing power consumption > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0278892 A1 - Document ID: US20210278892A1 - Status: Published application - Kind: A1 - Application number: 16/884,055 - Filed: 2020-05-27 - Published: 2021-09-09 - Earliest claimed: 2020-03-09 - Assignees: Silicon Motion, Inc. - Applicants: Silicon Motion, Inc. - Inventors: Kuo-Cyuan Kuo; Chih-Chiang Chen; I-Ta Chen - Web page: https://patentgrep.com/patent/US20210278892A1 ## CPC - G06F 1/3296: by lowering the supply or operating voltage - G06F 1/04: Generating or distributing clock signals or signals derived directly therefrom - G06F 1/325: {Power saving in peripheral device} - G06F 1/3253: {Power saving in bus} - G06F 13/4221: {being an input/output bus, e.g. ISA bus, EISA bus, PCI bus, SCSI bus} - G06F 2213/0026: PCI express - Y02D 10/00: Energy efficient computing, e.g. low power processors, power management or thermal management - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract An electronic device comprises a clock request pad, a multiplexer and a control circuit. The clock request pad is arranged to refer to a first control signal to operate under a low voltage level or a high voltage level, to indicate whether the electronic device needs a clock signal generated from a clock generation circuit external to the electronic device. Said multiplexer is arranged to refer to a second control signal to output one of a voltage level of the clock request pad and a predetermined voltage level to function as a multiplexer output signal. The control circuit is coupled to said multiplexer, and refers to said multiplexer output signal to determine whether to control the electronic device to operate in a power-saving mode. ## Claims ### Claim 1 An electronic device, comprising: a clock request pad, wherein the clock request pad is controlled by a first control signal to have a low voltage level or a high voltage level, to indicate whether the electronic device needs a clock signal generated from a clock generation circuit external to the electronic device or not; a multiplexer, wherein the multiplexer is controlled by a second control signal to output one of a voltage level of the clock request pad and a predetermined voltage level to function as a multiplexer output signal; and a control circuit, coupled to said multiplexer, the control circuit refers to said multiplexer output signal to determine whether to control the electronic device to operate in a power-saving mode. ### Claim 2 (depends on 1) The electronic device of claim 1, wherein the electronic device is an electronic device having a Peripheral Component Interconnect Express (PCIe) interface. ### Claim 3 (depends on 1) The electronic device of claim 1, wherein when the electronic device needs the clock signal generated from the clock generation circuit to perform operations, the control circuit generates the first control signal to make the clock request pad have the low voltage level, and the control circuit generates the second control signal to make said multiplexer output the voltage level of the clock request pad as said multiplexer output signal; and when the electronic device needs to enter the power-saving mode, the control circuit generates the first control signal in an attempt to control the clock request pad to have the high voltage level. ### Claim 4 (depends on 3) The electronic device of claim 3, wherein when the control circuit generates the first control signal in an attempt to make the clock request pad to have the high voltage level, and if the clock request pad remains in the low voltage level, the control circuit generates the second control signal to output the predetermined voltage level to function as said multiplexer output signal. ### Claim 5 (depends on 4) The electronic device of claim 4, wherein the predetermined voltage level has a high voltage level. ### Claim 6 (canceled) ### Claim 7 (depends on 3) The electronic device of claim 3, wherein when the electronic device needs to enter the power-saving mode, the control circuit further generates the second control signal to output the predetermined voltage level to function as said multiplexer output signal. ### Claim 8 (depends on 7) The electronic device of claim 7, wherein the predetermined voltage level has a high voltage level. ### Claim 9 A control method of an electronic device, comprising: generating a first control signal to a clock request pad to make the clock request pad have a low voltage level; receiving a clock signal generated from a clock generation circuit external to the electronic device to perform operations; generating a second control signal to output one of a voltage level of the clock request pad and a predetermined voltage level to function as a multiplexer output signal; and referring to said multiplexer output signal to determine whether to control the electronic device to operate in a power-saving mode. ### Claim 10 (depends on 9) The control method of claim 9, wherein the electronic device is an electronic device that has a Peripheral Component Interconnect Express (PCIe) interface. ### Claim 11 (depends on 9) The control method of claim 9, wherein the step of generating the second control signal to output one of the voltage level of the clock request pad and the predetermined voltage level to function as said multiplexer output signal comprises: when the electronic device needs the clock signal generated from the clock generation circuit to perform operations, generating the second control signal to make said multiplexer output the voltage level of the clock request pad to function as said multiplexer output signal. ### Claim 12 (depends on 11) The control method of claim 11, further comprising: when the electronic device needs to enter the power-saving mode, generating the first control signal in an attempt to make the clock request pad have high voltage level; and upon generating the first control signal in an attempt to make the clock request pad have the high voltage level, if the clock request pad remains in the low voltage level, generating the second control signal to output the predetermined voltage level to function as said multiplexer output signal. ### Claim 13 (depends on 11) The control method of claim 11, wherein the predetermined voltage level has a high voltage level. ### Claim 14 (canceled) ### Claim 15 (depends on 11) The control method of claim 11, further comprising: when the electronic device needs to enter the power-saving mode, generating the second control signal to output the predetermined voltage level to function as said multiplexer output signal. ### Claim 16 (depends on 15) The control method of claim 15, wherein the predetermined voltage level has a high voltage level.