# US 11,029,750 B2 · Apparatus for universal serial bus 2.0 (USB2) combined high speed squelch and disconnect detection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,029,750 B2 - Document ID: US11029750B2 - Status: Granted - Kind: B2 - Application number: 15/638,049 - Filed: 2017-06-29 - Published: 2019-01-03 - Granted: 2021-06-08 - Earliest claimed: 2017-06-29 - Assignees: Intel Corporation - Applicants: Intel Corporation - Inventors: Amit Kumar Srivastava; Chenchu Punnarao Bandi - Web page: https://patentgrep.com/patent/US11029750B2 ## CPC - G06F 1/3287: by switching off individual functional units in the computer system - G06F 1/3215: Monitoring of peripheral devices - G06F 1/3253: {Power saving in bus} - G06F 13/4022: {using switching circuits, e.g. switching matrix, connection or expansion network (G06F13/4009 takes precedence)} - G06F 13/4282: {on a serial bus, e.g. I2C bus, SPI bus (on daisy chain buses G06F13/4247)} - G06F 13/40: Bus structure {(for computer networks G06F15/163; for optical bus networks H04B10/25)} - G06F 13/42: Bus transfer protocol, e.g. handshake; Synchronisation - 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 Apparatus for managing high speed Universal Serial Bus 2.0 (USB2) communications is presented. The apparatus may include a combination differential difference detector to receive first and second input signals, the combination differential difference detector to, in a first mode: sense a first voltage difference between the first and second input signals and output a squelch signal when the first voltage difference is less than or equal to a pre-defined value. The combination differential difference detector is to, in a second mode, sense a second voltage difference between the first and second input signals and output a disconnect signal when the second voltage difference is greater than or equal to a pre-defined value. Related methods may also be disclosed. ## Claims ### Claim 1 An apparatus for managing high speed Universal Serial Bus 2.0 (USB2) communications, comprising: a combination differential difference detector to receive first and second input signals detected on a USB2 bus, the combination differential difference detector to, in a receive mode: sense a first voltage difference between the first and second input signals and output a squelch state signal when the first voltage difference is less than or equal to a first pre-defined value, the first voltage difference denoting either a squelch state or an un-squelch state; and to, in a transmit mode: sense a second voltage difference between the first and second input signals and output a disconnect state signal when the second voltage difference is greater than or equal to a second pre-defined value, the second voltage difference denoting either a connect state or a disconnect state, and the first and second pre-defined values being different pre-defined values; wrapper logic coupled to the combination differential difference detector, the wrapper logic to initiate common mode (CM) adjustment training to enable the combination differential difference detector to be used for either the receive mode or the transmit mode, and to enable the combination differential difference detector to operate in either the receive mode or the transmit mode; and a bias voltage and bias current generator, coupled to each of the combination differential difference detector and the wrapper logic, to provide a first reference current and first reference voltages to the combination differential difference detector in the receive mode, and to provide a second reference current and second reference voltages to the combination differential difference detector in the transmit mode, the first and second reference currents being different reference currents, and the first and second reference voltages being different reference voltages. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein, in the receive mode, the squelch state signal is outputted in response to the first voltage difference being <=100 millivolts (mV). ### Claim 3 (depends on 1) The apparatus of claim 1, wherein, in the transmit mode, the disconnect state signal is outputted in response to the second voltage difference being >=625 mV. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the wrapper logic is further to receive a USB2 transmit valid signal and, based at least in part on the transmit valid signal, generate internal signals for the transmit mode. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the wrapper logic is further to receive a USB2 receive active signal and, based at least in part on the receive active signal, generate internal biases for the receive mode. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the wrapper logic further comprises a first calibration logic and a second calibration logic. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the wrapper logic is to further enable a calibration mode that is to be entered into prior to either of the receive mode or the transmit mode. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein, in the calibration mode, the wrapper logic is to further initiate offset training. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein, when the offset training is complete, the wrapper logic is to store a first calibration configuration. ### Claim 10 (depends on 8) The apparatus of claim 8, wherein the wrapper logic initiates one or more common mode (CM) adjusters external to the wrapper logic to perform the CM adjustment training, following the offset training. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein, when the CM adjustment training is complete, the wrapper logic is to further store a second calibration configuration. ### Claim 12 (depends on 9) The apparatus of claim 9, wherein, prior to entering into either of the receive mode or the transmit modes, the wrapper logic is to further load the first calibration configuration. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein, following storage of the first calibration configuration and prior to enabling the combination differential difference detector to operate in either the receive mode or the transmit mode, the wrapper logic is further to initiate a high speed End Of Packet (EOP) detection. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein: in response to a detection off an EOP, the wrapper logic is to cause the combination differential difference detector to enter the transmit mode; and in response to -non-detection of an EOP, the wrapper logic is to cause the combination differential difference detector to enter the receive mode. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein, after enabling the combination differential difference detector to enters the transmit mode, the wrapper logic is to further load the second calibration configuration. ### Claim 16 (depends on 1) The apparatus of claim 1, wherein, in the transmit mode, the output of the disconnect state signal includes performance of EOP based filtering and transmission of the disconnect state signal to the wrapper logic. ### Claim 17 A method of managing high speed USB2 communications, comprising: using a combination differential difference detector, receiving differential positive (VDP) and differential negative (VDM) voltage signals detected over a USB2 connection; and selecting the combination differential difference detector to operate in either a receive mode or a transmit mode, wherein, in the receive mode: the combination differential difference detector senses a first voltage difference between the VDP and VDM signals and outputs a squelch state signal when the first voltage difference is less than or equal to a first pre-defined value, the first voltage difference indicating either a squelch state or a non-squelch state, and in the transmit mode: the combination differential difference detector senses a second voltage difference between the VDP and VDM signals and outputs a disconnect state signal when the second voltage difference is greater than or equal to a second pre-defined value, the second voltage difference indicating either a connect state or a disconnect state, and the first and second pre-defined values being different pre-defined values; wherein the method further comprises prior to selecting the combination differential difference detector to operate in either the receive mode or the transmit mode, initiating common mode (CM) adjustment training to enable the combination differential difference detector to be used for either the receive mode or the transmit mode, and on selecting the combination differential difference detector to operate in either the receive mode or the transmit mode, providing a first reference current and first reference voltages to the combination differential difference detector in response to selecting the receive mode, and providing a second reference current and second reference voltages to the combination differential difference detector in response to selecting the transmit mode, the first and second reference currents being different reference currents, and the first and second reference voltages being different reference voltages. ### Claim 18 (depends on 17) The method of claim 17, further comprising, prior to the combination differential difference detector sensing in either the receive mode or the transmit modes, obtaining and storing an offset calibration configuration and a common mode adjustment calibration configuration. ### Claim 19 (depends on 17) The method of claim 17, further comprising, prior to the combination differential difference detector sensing in the receive mode, loading an offset calibration configuration. ### Claim 20 (depends on 17) The method of claim 17, further comprising, prior to sensing in the transmit mode, first loading an offset calibration configuration, and then loading a common mode adjustment calibration configuration. ### Claim 21 (depends on 17) The method of claim 17, wherein, in the receive mode, the combination differential difference detector outputs the squelch state signal in response to the first voltage difference is <=100 mV. ### Claim 22 (depends on 17) The method of claim 17, wherein, in the transmit mode, combination differential difference detector outputs a disconnect state signal in response to the second voltage is >=625 mV. ### Claim 23 (depends on 17) The method of claim 17, further comprising, prior to selecting the combination differential difference detector to operate in either the receive mode or the transmits mode, entering a calibration mode comprising offset training. ### Claim 24 (depends on 23) The method of claim 23, wherein the initiating of CM adjustment training follows the offset training. ### Claim 25 (depends on 24) The method of claim 24, further comprising, when the offset training is complete, storing a first calibration configuration in the combination differential difference detector, and when the CM adjustment training is complete, storing a second calibration configuration in the combination differential difference detector.