Electronic device for detecting proximity of user and operation method thereof

• US 10,649,599 B2
• Filed: 06/28/2018
• Issued: 05/12/2020
• Est. Priority Date: 06/30/2017
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Seon-Jun, Yang, Dongil, Na, Hyoseok
• Primary Examiner(s): Lee, Laurence J
• Application Number:
  US16/021,237
• Publication Number:
  US 20190004628A1
• Time in Patent Office: 684 Days
• CPC Class Codes: G01V 3/088 operating with electric fields G01V3/082 takes precedence
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H04M 2250/12 including a sensor for measuring a physical value, e.g. temperature or motion

Abstract

Various embodiments of the present disclosure relate to an electronic device for using an amplifier to detect whether a user body is close to the electronic device and an operation method thereof. An electronic device according to an embodiment of the present disclosure may include: an antenna configured to be at least a part of an exterior of the electronic device; a variable element that has a capacitance in a designated range; and an amplifier connected to the variable element and configured to amplify a voltage of the variable element by a designated ratio and output an amplified voltage, wherein the capacitance of the variable element and the designated ratio may be configured so that a difference between a voltage of the antenna and the amplified voltage of the amplifier is smaller than a designated threshold value.

Claims

1. An electronic device for detecting proximity of a user comprising:

an antenna configured to be at least a part of an exterior of the electronic device, wherein a voltage of the antenna is a voltage of a reference capacitor serving as an equivalent circuit for the antenna, the reference capacitor having a capacitance corresponding to at least one capacitor connected to the antenna;

a variable element configured to have a capacitance in a designated range, wherein an upper limit of the designated range is smaller than the capacitance of the reference capacitor; and

an amplifier connected to the variable element and configured to amplify a voltage of the variable element to a voltage of the reference capacitor and output the amplified voltage,

wherein the capacitance of the reference capacitor corresponds to a first change rate of the voltage of the reference capacitor during a designated time interval.

2. The electronic device of claim 1, further comprising a detection circuit including a first input port connected to the antenna and a second input port connected to the amplifier, wherein the detection circuit is configured to:

identify at least two input voltages input to the first input port and the second input port and a difference between the at least two input voltages; and

output an output signal indicating the difference between the at least two input voltages.

3. The electronic device of claim 2, wherein one of the at least two input voltages is the amplified voltage of the amplifier, and

an other one of the at least two input voltages is the voltage of the reference capacitor when the electronic device is not close to a user body or a voltage of an equivalent capacitor of the reference capacitor and a capacitor virtually formed by proximity of the user body, when the electronic device is close to the user body.

4. The electronic device of claim 3, further comprising a processor, wherein the processor is configured to:

obtain the output signal from the detection circuit, and

when the difference between the at least two input voltages included in the output signal satisfies a designated condition, output a signal corresponding to the proximity of the user body to the electronic device.

5. The electronic device of claim 4, wherein the designated condition is a condition wherein the difference between the at least two input voltages is equal to or greater than a pre-configured threshold value.

6. The electronic device of claim 5, wherein the pre-configured threshold value is configured based on the capacitance of the reference capacitor.

7. The electronic device of claim 4, wherein the processor is further configured to, when a second change rate of the amplified voltage of the amplifier during a predetermined time interval is greater than a third change rate of the voltage of the reference capacitor during the predetermined time interval, change a designated ratio so that the amplifier amplifies the voltage of the variable element by the changed designated ratio.

8. The electronic device of claim 7, wherein the amplifier is further configured to, until the second change rate of the amplified voltage of the amplifier during the predetermined time interval is smaller than the third change rate of the voltage of the reference capacitor during the predetermined time interval, repeatedly change the designated ratio.

9. The electronic device of claim 8, wherein the processor is further configured to, when the second change rate of the amplified voltage of the amplifier during the predetermined time interval is smaller than the third change rate of the voltage of the reference capacitor during the predetermined time interval, change the capacitance of the variable element within the designated range so that the difference between the voltage of the reference capacitor and the amplified voltage of the amplifier is smaller than a designated threshold value.

10. The electronic device of claim 7, wherein the changed designated ratio is determined based on at least one of a representative value of the designated range of the variable element and the capacitance of the reference capacitor.

11. An electronic device for detecting proximity of a user comprising:

an antenna, wherein a voltage of the antenna is a voltage of a reference capacitor serving as an equivalent circuit for the antenna, the reference capacitor having a capacitance corresponding to at least one capacitor connected to the antenna;

a variable element configured to have a capacitance in a designated range, wherein an upper limit of the designated range is smaller than the capacitance of the reference capacitor; and

an amplifier connected to the variable element and configured to amplify a voltage of the variable element to a voltage of the reference capacitor and output the amplified voltage,

wherein the capacitance of the reference capacitor corresponds to a first change rate of the voltage of the reference capacitor during a designated time interval.

12. The electronic device of claim 11, further comprising a detection circuit including a first input port connected to the antenna and a second input port connected to the amplifier, wherein the detection circuit is configured to:

identify at least two input voltages input to the first input port and the second input port and a difference between the at least two input voltages; and

output an output signal indicating the difference between the at least two input voltages.

13. The electronic device of claim 12, wherein:

one of the at least two input voltages is the amplified voltage of the amplifier; and

an other one of the at least two input voltages is the voltage of the reference capacitor when the electronic device is not close to a user body or a voltage of an equivalent capacitor of the reference capacitor and a capacitor virtually formed by proximity of the user body, when the electronic device is close to the user body.

14. An operation method of an electronic device configured to detect whether a user is close, the operation method comprising:

identifying a change rate during a predetermined time interval of an output voltage of an amplifier configured to amplify, by a designated ratio, a voltage of a variable element configured to have a capacitance in a designated range;

identifying a change rate during the predetermined time interval of a voltage of a reference capacitor serving as an equivalent circuit for an antenna;

determining whether the identified change rate of the output voltage of the amplifier during the predetermined time interval is greater than the change rate of the voltage of the reference capacitor during the predetermined time interval; and

changing the designated ratio of the amplifier in response to determining that the identified change rate of the output voltage of the amplifier during the predetermined time interval is greater than the change rate of the voltage of the reference capacitor during the predetermined time interval.

15. The operation method of claim 14, wherein the changing of the designated ratio of the amplifier comprises repeatedly changing the designated ratio of the amplifier until the identified change rate of the output voltage of the amplifier during the predetermined time interval is smaller than the change rate of the voltage of the reference capacitor during the predetermined time interval.

16. The operation method of claim 15, further comprising, when the change rate of the output voltage of the amplifier during the predetermined time interval is smaller than the change rate of the voltage of the reference capacitor during the predetermined time interval, changing the capacitance of the variable element within the designated range so that a difference between the voltage of the reference capacitor and the output voltage of the amplifier is smaller than a designated threshold value.

17. The operation method of claim 16, further comprising:

identifying, when the difference between the voltage of the reference capacitor and the output voltage of the amplifier is smaller than the designated threshold value, the output voltage of the amplifier, the voltage of the reference capacitor, and the difference between the voltages; and

outputting, when the identified difference between the voltages satisfies a designated condition, a signal corresponding to proximity of a user body of the user to the electronic device,

wherein, when the electronic device is close to the user body, the voltage of the reference capacitor is a voltage of an equivalent capacitor of the reference capacitor and a capacitor virtually formed by the proximity of the user body.

18. The operation method of claim 14, wherein the designated ratio is changed based on at least one of a representative value of the designated range of the variable element and a capacitance value of the reference capacitor.

19. The operation method of claim 18, wherein the changed designated ratio is a ratio by which the output voltage of the amplifier is synchronized with the voltage of the reference capacitor when the capacitance of the variable element is determined to be the representative value.