Abstract: Common-mode transient immunity circuit and modulation-demodulation circuit, common-mode transient immunity circuit is applied to connecting with modulation circuit or demodulation circuit, comprising first isolation circuit, common-mode bias circuit, reference circuit and comparison circuit. Common-mode bias circuit provides common-mode bias voltage for first isolation circuit; first isolation circuit transmits common-mode bias voltage to comparison circuit; reference circuit provides reference voltage for comparison circuit; comparison circuit compares common-mode bias voltage with reference voltage, when common-mode bias voltage is larger than reference voltage, comparison circuit outputs enable signal to modulation circuit or demodulation circuit, and modulation circuit is driven to stop outputting modulation signal or demodulation circuit is driven to stop receiving modulation signal.

Abstract: The present disclosure relates to telephone jack covering systems that advantageously render existing telephone jacks more attractive and useful. The systems disclosed include a novel bracket that allows for existing telephone jacks to be covered with decorative and functional devices. In a preferred embodiment, an existing telephone jack is outfitted with a bracket and covered with a converter device that converts the existing telephone jack into a smart device charging station.

Abstract: A telecommunications enclosure having a door hingedly attached to a chassis. The chassis has a first through-hole configured to have at least one patching panel installed therein. A different enclosure, like the telecommunications enclosure, is mountable on the door. The door is rotatable relative to the chassis between closed and open positions when the different enclosure is mounted thereto. The door allows access to an interior of the chassis when the door is in the open position. The chassis and/or the door may have a second through-hole configured to allow a telecommunications cable connected to the at least one patching panel to pass therethrough and exit the interior of the chassis.

Abstract: Provided is a vehicle display device such that the responsiveness of communication between a main microcomputer and a sub microcomputer is improved. The vehicle display device is equipped with a main microcomputer that generates information data and a sub microcomputer that generates an image to be displayed on a display element on the basis of the information data. Between the main microcomputer and the sub microcomputer, at least a signal line for data transmission and a signal line for chip select signal transmission are connected so as to allow communication between the main microcomputer and the sub microcomputer. The vehicle display device synchronizes a first timer counter counted by the main microcomputer and a second timer counter counted by the sub microcomputer, in response to the tip select signal transmitted to the sub microcomputer by the main microcomputer.

Abstract: Certain types of fiber termination enclosures include an enclosure and at least one of a plurality of plate module mounting assemblies. Example plate module mounting assemblies include a termination panel plate assembly; a splice tray plate assembly; a cable spool plate assembly; and a drop-in plate assembly. Example cable spool plate assemblies include a cable spool arrangement rotationally coupled to a mounting plate, which fixedly mounts within the enclosure housing. A stand-off mount element may be disposed on the front of the cable spool arrangement to rotate in unison with the cable spool arrangement. The stand-off mount element may include one or more termination adapters.

Abstract: A network interface device includes a housing. The housing includes a base and a cover, the cover connected to the base and movable relative to the base between an open position and a closed position. The network interface device further includes an insert removably connectable to the base. The insert includes a base plate, and an adapter plate extending from the base plate and defining a subscriber section of the insert and a provider section of the insert. The subscriber section and provider section are opposite each other relative to the adapter plate. The adapter plate defines one or more adapter apertures extending therethrough. The insert further includes an organizer arm which includes a support member, an upper portion extending from the support member, and a lower portion extending from the support member opposite the upper portion.

Abstract: A telecommunication distribution box includes a housing and an electrical component mounted in the housing. A cover plate is movably connected to the housing and is movable between open and closed positions. A lip extends outwardly from the cover plate. The lip covers the electrical component when the cover plate is in the closed position to prevent accessing and removing the electrical component.

Abstract: Damages to the rectifying MOSFET in the secondary side of voltage converters are reduced or eliminated by inserting intermediary steps between detecting a dropping in the converter output voltage VCC and activating the under voltage lock out (UVLO) circuitry. During the intermediary steps, the timing for switching off the MOSFET is advanced to prevent the current flow in the MOSFET from reversing its direction.

Abstract: A surge protection circuit includes a first terminal that is coupled to a transmission path, a second terminal that is coupled to a PHY circuit to transfer a signal on a physical layer, a clamping unit that is coupled so as to branch from a first line between the first terminal and the second terminal, the clamping unit clamping a voltage applied to the first terminal to a specific clamping voltage, and a first semiconductor switch that is arranged between the second terminal and a branching point at which the clamping unit branches from the first line, the first semiconductor switch having a rectification direction away from the second terminal toward the first terminal, the first semiconductor switch having a higher reverse breakdown voltage than a clamping voltage of the clamping unit.

Abstract: A device includes a plurality of subscriber line interface circuits and a shared protection device. Each subscriber line interface circuit has a voltage input terminal and first and second interface line terminals. The shared protection device is coupled to the interface line terminals and operable to sense a negative reference voltage representing a most negative one of the voltages present on the voltage input terminals and to provide overvoltage protection responsive to a voltage on at least one of the interface line terminals exceeding the negative reference voltage.

Abstract: Various systems and methods for probing a communication channel. These systems and methods transmit an error vector probe packet from a first transmitter while a second transmitter is active and transmitting. A network device may receive the error vector probe packet and measure an error vector magnitude based on the received error vector probe packet. Using the error vector magnitude, the network device estimates channel characteristics such as signal-to-noise ratio, data capacity, etc. The transmission can occur when more than one transmitter is active and transmitting. At least some of the other transmitters are active and transmit an analog zero signal, e.g., all digital zeros on the input to the digital-to-analog converter of a network device when an error vector probe packet is transmitted.

Abstract: In order to provide unbalanced ringing when an exchange line card provides a balanced ringing output the interface provides a ringing detector in circuit with a customer pair. On detecting balanced ringing signals from the line card, the interface takes over the customer line pair and provides unbalanced ringing signals to the customer and monitors for customer answer. By inserting the interface in circuit at the main distribution frame of an exchange, legacy customer premises equipment which is unable to respond to balanced signalling can be provided with an appropriate ringing signal without the necessity to provide differing line cards at the exchange.

Abstract: A method of generating a plurality of supply voltages for a plurality of subscriber line channels includes generating a first target VBAT value for a first associated linefeed driver from a first VBAT control. A second target VBAT value for a second associated linefeed driver is generated from a second VBAT control. A selected target VBAT value is generated based upon the first and second target VBAT values. A magnitude of the selected target VBAT value is not less than any maximum of a magnitude of the first and second target VBAT values. A switching regulator is controlled to provide a first generated VBAT corresponding to the selected target VBAT value, wherein the switching regulator provides a second generated VBAT having a pre-determined proportional relationship (p) to the first generated VBAT.

Abstract: A line card includes a plurality of subscriber line interface circuits, a plurality of interface lines, and a first overvoltage protector. The subscriber line interface circuits each have a first input terminal operable to receive power at a first positive reference voltage. The interface lines are each coupled to one of the subscriber line interface circuits for interfacing with subscriber lines external to the line card. The first overvoltage protector is coupled to the interface lines and referenced to the first positive reference voltage to provide overvoltage protection responsive to a voltage on at least one of the interface lines exceeding the first positive reference voltage.

Abstract: In accordance with a non-limiting example, an electrical protection device includes a fuse housing and a plurality of fuses carried by the fuse housing and arranged in a plurality of Tip/Ring fuse pairs. The Tip/Ring fuse pairs are arranged in vertical and horizontal orientation of Tip/Ring fuse pairs and spaced to each other such that differential crosstalk among the Tip/Ring fuse pairs is cancelled.

Abstract: An integrated access device (IAD) protects overcurrent of a DAA chipset. The IAD periodically detects an on-hook/off-hook state of the DAA chipset, and periodically monitors an OPD state of the DAA chipset upon the condition that the on-hook/off-hook state of the DAA chipset is detected in off-hook state at least twice. The IAD further sets the on-hook/off-hook state of the DAA chipset as on-hook to avoid damage to the DAA chipset caused by overcurrent upon the condition that the OPD state of the DAA chipset indicates the DAA chipset is overcurrent.

Abstract: In a telephone interface circuit, a first NPN transistor switch-controls a connection between a speech circuit and a pair of subscriber lines. A second PNP transistor controls an on/off state of the first transistor. A positive feedback circuit connects a collector terminal of the first transistor to a base terminal of the second transistor. An internal power source supplies current for driving the second transistor. The first transistor operates in a saturated region when a voltage that is in a range of standard voltages delivered over a pair of subscriber lines for normal operating conditions of a subscriber line device that is not being subjected to an over-voltage or an over-current event is applied in between the pair of the subscriber lines. The first transistor operates in an unsaturated region when an overvoltage exceeding said range of standard voltages is applied in between the pair of the subscriber lines.

Abstract: A line card includes a subscriber line interface circuit, an interface line, and a first overvoltage protector. The subscriber line interface circuit has a first input terminal operable to receive power at a first reference voltage. The interface line is coupled to the subscriber line interface circuit for interfacing with a subscriber line external to the line card. The first overvoltage protector is coupled to the interface line and referenced to the first reference voltage to provide overvoltage protection responsive to a voltage on the interface line exceeding the first reference voltage by a first predetermined threshold.

Abstract: A differential transformer-free hybrid circuit includes a first amplifier configured to receive a first signal from a transmitter and output the first signal to a telephone loop, and a second amplifier configured to receive a second signal from the telephone loop and output the second signal to a receiver. Further, the differential transformer-free hybrid circuit also includes at least one balanced network element and a transformer-less interface configured to couple the first amplifier and the second amplifier to the telephone loop, wherein the transformer-less interface includes at least one current blocking device.

Abstract: The invention relates to a remote unit for use in conjunction with a communications network. The remote unit includes a network interface which provides an interface between a premises communication system and a first network. The interface permits the premises communication system to receive at least one service over the first network. The remote unit also includes a detector for detecting a cross-connection to a second network which is also connected to the premises communication system.

Abstract: A port detection and protection circuit utilizes a voltage detection circuits to output a detection signal according to a voltage difference between the tip signal and the ring signal and utilizes a ring detection circuit to output another detection signal according to a voltage difference between a Subscriber Line Interface Circuit (SLIC) tip signal and a SLIC ring signal signaling an incoming call. In addition, the port detection and protection circuit utilizes at least one logic component to output logic signals according to the detection signals. The port detection and protection circuit further switches a loop of a tip wire, a ring wire and the SLIC on or/and off based on logic signals, and issues an alarm according to the logic signals.

Abstract: In described embodiments, a data communication device employing, for example, a modem and a data access arrangement (DAA) electrically connected to a telephone network has an increased surge immunity through use of improved hook switch driver and line modulation driver circuitry. In accordance with described embodiments, hook switch driver circuitry exhibits decreased surge power dissipation by maintaining the hook switch driver transistors in saturation at higher currents while reducing the collector-emitter voltage across hook switch driver transistors, and line modulation driver circuitry exhibits decreased total surge power dissipation by i) limiting surge voltage ii) over voltage stress of the line driver transistor.

Abstract: In a particular embodiment, a circuit device includes a first circuit having a first plurality of serial terminals including a first data receive terminal and a first data transmit terminal. The first plurality of serial terminals is communicatively coupled to a particular circuit via isolation circuitry to communicate first serial data. The circuit device further includes a second circuit having a second plurality of serial terminals including a second data receive terminal coupled to the first data transmit terminal and including a second data transmit terminal coupled to the first data receive terminal to communicate second serial data to the particular circuit via the first data receive and transmit terminals.

Abstract: A device includes a plurality of subscriber line interface circuits and a shared protection device. Each subscriber line interface circuit has a voltage input terminal and first and second interface line terminals. The shared protection device is coupled to the interface line terminals and operable to sense a negative reference voltage representing a most negative one of the voltages present on the voltage input terminals and to provide overvoltage protection responsive to a voltage on at least one of the interface line terminals exceeding the negative reference voltage.

Abstract: Disclosed herein is a transmission/reception channel matching apparatus for a mobile communication terminal and a mobile phone test equipment. The transmission/reception channel matching apparatus includes a Printed Circuit Board (PCB), a Dual In-line Package (DIP) switch, and a fastening casing. The PCB includes mobile communication terminal-side terminals to be electrically connected to option pins provided in the serial communication connector of the mobile communication terminal, and transmission and reception terminals corresponding to the transmission and reception channels of the mobile phone test equipment for transmitting a transmission signal to the mobile communication terminal and receiving a reception signal from the mobile communication terminal. The DIP switch is provided with a plurality of switches, is combined with the PCB, and selectively connects the mobile communication terminal-side terminals to the transmission and reception terminals depending on ON/OFF information.

Abstract: A power system includes a switch, a capacitor and a comparator circuit. The power system receives a signal to turn off power supplied to the power system, turns off the switch that is used to supply power to the system and discharges the capacitor. The power system also compares a voltage across the discharging capacitor to a threshold voltage value, and turns on the switch to allow power to be supplied to the power system when the compared voltage across the discharging capacitor equals the threshold voltage value.

Abstract: A method of controlling a switching regulator includes setting a current limit (ILIM) to a first value, ILIM1. An error voltage (VERR) is computed as a difference between an output voltage VOUT of the switching regulator and a reference voltage VREF of the switching regulator. The switching regulator current limit is set to a second value ILIM2, if the error voltage is greater than a first threshold voltage, VTH1. The switching regulator current limit is set to the first value, if the error voltage does not exceed a second threshold value, VTH2.

Abstract: A powered device includes a first switch, a second switch, and a controller. The first switch is disposed between a center tap of the first transformer and a center tap of the third transformer. The second switch is disposed between a center tap of the second transformer and a center tap of the fourth transformer. The controller is coupled to the first switch and the second switch. The controller is constructed and arranged to output a control signal to the first and second switches to electrically connect the center taps of the first and third transformers together and concurrently electrically connect the center taps of the second and fourth transformers together. The powered device is constructed and arranged to operate in 4-pair mode when the center taps of the first and third transformers are connected together and the center taps of the second and fourth transformers are connected together.

Abstract: An Ethernet extension device is provided for metro or last mile Ethernet service via twisted pairs as opposed to fiber optics. The Ethernet extension device is implemented as a plug-in extension for existing infrastructure (e.g., in a standard electrical wall box or Type-200™ Mechanics card) that employs lighting and power cross protection required by the telephone companies for Ethernet connectivity to the telephone network (e.g., for connection between a user's building and a telephone company building over existing outdoor telephone cables).

Abstract: The invention relates to a protected plug socket (20) for distribution devices in telecommunications and data technology, comprising at least one housing (21) and at least one protective element (12), said protective element (12) comprising at least two contact posts (9-11), at least two contact elements (24a-c) being embedded in the housing (21), the contact elements (24a-c) each comprising a line contact (22a, b) and a clamping contact (24a-c), wherein the line contact (22a, b) is arranged in a plugging-in region and the clamping contact is arranged in a housing region of the protected plug socket (20).

Abstract: Embodiments disclosed herein describe a network device including a class AB common mode suppression (CMS) circuit coupled in parallel between a line voltage source and a physical layer (PHY) device that provides active EMI suppression and Phy device termination. A network connector is coupled to provide the line voltage source to the class AB CMS circuit. The class AB CMS circuit provides current to the PHY device, terminates open-drain transmit drivers of the PHY device and suppresses common mode noise thereby minimizing electromagnetic interference. In other embodiments, the class AB CMS circuit is coupled in parallel between the network connector and a physical layer (PHY) device. The class AB CMS circuit suppresses common mode noise, and terminates open-drain transmit drivers of the PHY device, thereby minimizing electromagnetic interference.

Abstract: A telephone interface circuit comprising a speech circuit, a control circuit turning on upon receiving a supply of a forward direction trigger current so as to connect first and second telephone lines and the speech circuit, and going off upon receiving a supply of a reverse direction trigger current so as to disconnect the first and second telephone lines and the speech circuit, a capacitor charging and discharging charge supplied from the first telephone line, and a hook switch supplying charge accumulated at the capacitor when off-hook to the control circuit as a forward direction trigger current, and supplying charge discharged from the capacitor when on-hook to the control circuit as a reverse direction trigger current.

Abstract: A system for improving the attenuation of an undesired signal found in a differential signal path through the use of inductive coupling. The system includes a primary inductor, a secondary inductor, and a filter. The primary inductor and the secondary inductor operably couple an input differential signal pair to an output differential signal pair, and the filter attenuates an undesired signal in the output differential signal pair.

Abstract: A line card includes a plurality of subscriber line interface circuits, a plurality of interface lines, and a first overvoltage protector. The subscriber line interface circuits each have a first input terminal operable to receive power at a first positive reference voltage. The interface lines are each coupled to one of the subscriber line interface circuits for interfacing with subscriber lines external to the line card. The first overvoltage protector is coupled to the interface lines and referenced to the first positive reference voltage to provide overvoltage protection responsive to a voltage on at least one of the interface lines exceeding the first positive reference voltage.

Abstract: A line card includes a subscriber line interface circuit, an interface line, and a first overvoltage protector. The subscriber line interface circuit has a first input terminal operable to receive power at a first reference voltage. The interface line is coupled to the subscriber line interface circuit for interfacing with a subscriber line external to the line card. The first overvoltage protector is coupled to the interface line and referenced to the first reference voltage to provide overvoltage protection responsive to a voltage on the interface line exceeding the first reference voltage by a first predetermined threshold.

Abstract: Transformer driven by data modulated signal provides isolated power. Outbound data is extracted from the data modulated signal received from the transformer. Inbound data received in isolated circuitry modulates the load presented to transformer. Inbound data perceived in non-isolated circuitry by sensing load experienced by the transformer.

Abstract: In described embodiments, a data communication device employing, for example, a modem and a data access arrangement (DAA) electrically connected to a telephone network has an increased surge immunity through use of improved hook switch driver and line modulation driver circuitry. In accordance with described embodiments, hook switch driver circuitry exhibits decreased surge power dissipation by maintaining the hook switch driver transistors in saturation at higher currents while reducing the collector-emitter voltage across hook switch driver transistors, and line modulation driver circuitry exhibits decreased total surge power dissipation by i) limiting surge voltage ii) over voltage stress of the line driver transistor.

Abstract: An integrated access device (IAD) protects overcurrent of a DAA chipset. The IAD periodically detects an on-hook/off-hook state of the DAA chipset, and periodically monitors an OPD state of the DAA chipset upon the condition that the on-hook/off-hook state of the DAA chipset is detected in off-hook state at least twice. The IAD further sets the on-hook/off-hook state of the DAA chipset as on-hook to avoid damage to the DAA chipset caused by overcurrent upon the condition that the OPD state of the DAA chipset indicates the DAA chipset is overcurrent.

Abstract: A port detection and protection circuit utilizes a voltage detection circuits to output a detection signal according to a voltage difference between the tip signal and the ring signal and utilizes a ring detection circuit to output another detection signal according to a voltage difference between a Subscriber Line Interface Circuit (SLIC) tip signal and a SLIC ring signal signaling an incoming call. In addition, the port detection and protection circuit utilizes at least one logic component to output logic signals according to the detection signals. The port detection and protection circuit further switches a loop of a tip wire, a ring wire and the SLIC on or/and off based on logic signals, and issues an alarm according to the logic signals.

Abstract: A telephone interface circuit comprises a first transistor for controlling opening and closing between a speech circuit and subscriber lines, a second transistor for controlling the first transistor to turn on and off, a positive feedback circuit connecting a collector terminal of the first transistor and a base terminal of the second transistor, an overcurrent detection circuit detecting overcurrent applied to the subscriber lines, and a breaker circuit for turning off the first transistor by lowering the base potential of the second transistor to a low potential when overcurrent is detected at the overcurrent detection circuit. Here, the base terminal of the first transistor and a collector terminal of the second transistor are connected. Further, when off-hook, the base potential of the second transistor is controlled in such a manner as to become a high potential by a microcomputer.

Abstract: Methodologies and structure are provided for use in a communications line that transmit data without plain old telephone service (POTS), or splits the POTS service from the data service, to inhibit oxidation of electrical connections within the physical communications line between the central office of a service provider and a subscriber premises and/or subscriber equipment. A direct current load is drawn by a sealing current terminator circuit that is electrically coupled across the communications line at a convenient location proximate or within the subscriber's location so as to assist in providing oxidation reducing direct current flow along a portion of the communications loop coupling the service provider with the subscriber.

Abstract: A sealing current system for a subscriber line that comprises a power source coupled to a first end of the subscriber line configured to apply a voltage to the subscriber line. The sealing current termination circuit coupled to a second end of the subscriber line configured to limit a current in the subscriber line, the current produced by the applied voltage.

Abstract: In a particular embodiment, a circuit device includes a first circuit having a first plurality of serial terminals including a first data receive terminal and a first data transmit terminal. The first plurality of serial terminals is communicatively coupled to a particular circuit via isolation circuitry to communicate first serial data. The circuit device further includes a second circuit having a second plurality of serial terminals including a second data receive terminal coupled to the first data transmit terminal and including a second data transmit terminal coupled to the first data receive terminal to communicate second serial data to the particular circuit via the first data receive and transmit terminals.

Abstract: The present invention discloses circuits for isolating and attenuating signals generated by a telephone network. In disclosed embodiments, a metering pulse signal is isolated from the terminals of the connecting device, and then attenuated with an impedance that is synthesized with a programmable digital signal processor. Embodiments also utilize the digital signal processor to synthesize a termination impedance for the connecting device. The termination impedance matches closely the characteristic impedance of the network, so as to minimize wave reflections and the like.

Abstract: A method of managing power at an element management system for a power sourcing network element and a power sinking network element of an access network is provided.

Abstract: An impedance blocking filter circuit is provided for use in telecommunication systems for interconnecting between incoming telephone lines and customer's terminal equipment so as to unconditionally block impedances above 20 KHz a desired frequency range due to the customer's terminal equipment from an ADSL a DSL network unit and/or home networking interface unit. The filter circuit includes first, second, and third inductors connected in series between a first input terminal and a first common point. A first resistor has its one end connected also to the first common point and its other end connected to a first output terminal. Fourth, fifth and sixth inductors are connected in series between a second input terminal and a second common point. A second resistor has its one end also connected to the second common point and its other end connected to a second output terminal. A capacitor has its ends connected across the first and second common points.

Abstract: An impedance blocking filter circuit is provided for use in telecommunication systems for interconnecting between incoming telephone lines and customer's terminal equipment so as to unconditionally block impedances above 20 KHz a desired frequency range due to the customer's terminal equipment from an ADSL a DSL network unit and/or home networking interface unit. The filter circuit includes first, second, and third inductors connected in series between a first input terminal and a first common point. A first resistor has its one end connected also to the first common point and its other end connected to a first output terminal. Fourth, fifth and sixth inductors are connected in series between a second input terminal and a second common point. A second resistor has its one end also connected to the second common point and its other end connected to a second output terminal. A capacitor has its ends connected across the first and second common points.

Abstract: An output reducing system for a telephone system, e.g., implemented in a headset, includes an input line and an output line, wherein the input line transmits an incoming signal to an output transducer and the output line transmits an outgoing signal from an input transducer, and a compressor system is provided in the input line for reducing the output signal level.

Abstract: The telephone line coupler circuit has a single transmit opto-coupler whose output includes a DC bias component connected to a gate of a line seize switch for connecting a DC line seize load across the ring and tip contacts of the telephone line. The line seize switch is saturated by the transmit opto-coupler bias output and the AC component of the transmit opto-coupler output is sent over the telephone lines. The receive opto-coupler is used both for receiving communications signal and for detecting the ring signal. The band pass filter connected to the output of the receive opto-coupler may be switched to pass a ring signal frequency band or a communications frequency band. The circuit operates using two opto-coupler devices while conventional circuits require four opto-coupler devices.

Abstract: An impedance blocking filter circuit is provided for use in telecommunication systems for interconnecting between incoming telephone lines and customer's terminal equipment so as to unconditionally block impedances above 20 KHz due to the customer's terminal equipment from an ADSL network unit and/or home networking interface unit. The filter circuit includes first, second, and third inductors connected in series between a first input terminal and a first common point. A first resistor has its one end connected also to the first common point and its other end connected to a first output terminal. Fourth, fifth and sixth inductors are connected in series between a second input terminal and a second common point. A second resistor has its one end also connected to the second common point and its other end connected to a second output terminal. A capacitor has its ends connected across the first and second common points.