Hack-proof security keyboard

• US 10,853,525 B2
• Filed: 04/16/2018
• Issued: 12/01/2020
• Est. Priority Date: 04/16/2018
• Status: Active Grant

• Current Assignee: Dell Products LP (Dell Technologies Inc.)
• Original Assignee: Dell Products LP (Dell Technologies Inc.)
• Inventors: Lin, Yong-Teng, Tan, Geroncio Ong, Shaw, Timothy C., Chuang, No-Hua, Chang, Erh-Chieh, Chen, Chih-Hao, Huang, Wen-Pin
• Primary Examiner(s): Mehedi, Morshed
• Application Number:
  US15/953,718
• Publication Number:
  US 20190318134A1
• Time in Patent Office: 960 Days
• CPC Class Codes: G06F 21/71 to assure secure computing or processing of information
• CPC Class Codes: G06F 21/83 input devices, e.g. keyboards, mice or controllers thereof
• CPC Class Codes: G06F 3/0202 Constructional details or processes of manufacture of the input device
• CPC Class Codes: G06F 3/0227 Cooperation and interconnection of the input arrangement with other functional units of a computer G06F3/023 - G06F3/037 take precedence
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 13/703 characterised by spacers between contact carrying layers
• CPC Class Codes: H01H 13/785 characterised by the material of the contacts, e.g. conductive polymers
• CPC Class Codes: H01H 13/807 characterised by the spatial arrangement of the contact sites, e.g. superimposed sites
• CPC Class Codes: H01H 2201/024 precious
• CPC Class Codes: H01H 2201/026 non precious
• CPC Class Codes: H01H 2215/004 Collapsible dome or bubble
• CPC Class Codes: H01H 2225/002 superimposed
• CPC Class Codes: H01H 2225/004 in different planes to increase density
• CPC Class Codes: H01H 2225/008 Two different sites for one circuit, e.g. for safety
• CPC Class Codes: H01H 2227/022 Collapsable dome
• CPC Class Codes: H01H 2300/052 Controlling, signalling or testing correct functioning of a switch see also H01H2300/056 - H01H2300/066 and H01H11/0062

Abstract

Systems and methods for a hack-proof security keyboard are described. In some embodiments, a keyboard module may include a first circuit configured to detect activation of a plurality of keys and a second circuit configured to detect activation of a subset of the plurality of keys, where the second circuit overlies the first circuit. In other embodiments, a method may include detecting an electrical signal received from a secondary membrane of a keyboard, where the keyboard includes a primary membrane configured to detect individual activation of any of a plurality of keys, and where the secondary membrane is configured to output the electrical signal in response to concurrent activation of a subset of the plurality of keys. The method may also include performing a selected action in response to the detection.

Claims

1. A keyboard module, comprising:

a first circuit configured to detect activation of a plurality of keys; and

a second circuit configured to detect activation of a subset of the plurality of keys to the exclusion of at least one key of the plurality of keys, wherein the second circuit overlies the first circuit.

2. The keyboard module of claim 1, wherein the first circuit comprises a row trace layer, a column trace layer, and a spacing layer between the row trace layer and the column trace layer.

3. The keyboard module of claim 2, wherein the first circuit is coupled to a metal plate via a first insulating layer, and wherein the second circuit is coupled to the first circuit via a second insulating layer.

4. The keyboard module of claim 3, wherein the second circuit comprises an input trace layer, an output trace layer, and another spacing layer between the input trace layer and the output trace layer.

5. The keyboard module of claim 3, wherein the second circuit comprises a single conductive trace layer.

6. The keyboard module of claim 5, wherein the single conductive trace layer further comprises a silver trace portion and a carbon trace portion overlying the silver trace portion.

7. The keyboard module of claim 6, wherein the single conductive trace layer forms a gap under each key of the subset of keys, and wherein each of the subset of keys comprises a conductive dome configured to close a corresponding gap.

8. The keyboard module of claim 7, wherein the conductive dome is a carbon dome.

9. The keyboard module of claim 1, wherein the second circuit couples each of a plurality of electrical switches in series, wherein each one of the plurality of switches corresponds to one key of the subset keys, and wherein concurrent activation of the subset of keys causes the second circuit to output a selected electrical signal.

10. The keyboard module of claim 9, wherein the selected electrical signal is configured to cause a reset or recovery operation of an Information Handling System (IHS) independently of any keystroke detection by the first circuit.

11. The keyboard module of claim 9, further comprising a third circuit configured to detect activation of another subset of the plurality of keys, wherein the third circuit overlies the first or second matrices, wherein the third circuit couples each of another plurality of electrical switches in series with respect to each other, and wherein concurrent activation of the other subset of keys causes the third circuit to output another electrical signal independently of any keystroke detection by any of the first or second matrices.

12. An Information Handling System (IHS), comprising:

a processor;

an embedded controller coupled to the processor; and

a keyboard coupled to the embedded controller, the keyboard comprising;

a plurality of keys;

a primary membrane configured to detect activation of any of the plurality of keys; and

a secondary membrane configured to detect concurrent activation of a subset of the plurality of keys to the exclusion of at least one key of the plurality of keys.

13. The IHS of claim 12, wherein the primary membrane comprises a row trace layer, a column trace layer, and a spacing layer between the row trace layer and the column trace layer.

14. The IHS of claim 13, wherein the secondary membrane comprises a conductive trace layer having a respective gap under each key of the subset of keys, and wherein each of the subset of keys comprises a conductive dome.

15. The IHS of claim 14, wherein the conductive trace layer comprises a silver trace portion and a carbon trace portion overlying the silver trace portion, and wherein the conductive dome is a carbon dome.

16. The IHS of claim 12, wherein the secondary membrane couples each of a plurality of electrical switches in series, wherein each one of the plurality of switches corresponds to one key of the subset keys, and wherein concurrent activation of the subset of keys causes the secondary membrane to output an electrical signal.

17. The IHS of claim 16, wherein the electrical signal triggers a predefined operation.

18. A method, comprising:

detecting an electrical signal received from a secondary membrane of a keyboard, wherein the keyboard comprises a primary membrane configured to detect individual activation of any of a plurality of keys, and wherein the secondary membrane is configured to output the electrical signal in response to concurrent activation of a subset of the plurality of keys to the exclusion of at least one key of the plurality of keys; and

performing a selected action in response to the detection.

19. The method of claim 18, wherein the selected action comprises a hardware reset operation.

20. The method of claim 18, wherein the selected action comprises a software recovery operation.