Abstract: A dual-mode IC is provided for operating in first mode such as an ISO mode in accordance with International Standards Organization 7816 (ISO 7816) protocol, and a second, non-ISO mode, such as a USB mode in accordance with Universal Serial Bus (USB) protocol. The dual-mode IC is preferably in a smart card and includes a microprocessor, a switching block, and an external interface. The external interface includes a voltage supply pad, a reference voltage pad, a reset pad, a clock pad and an input/output pad in accordance with the ISO 7816 protocol, and a D-plus pad and D-minus pad in accordance with the USB protocol. The IC further includes a mode configuration circuit for detecting a USB mode condition on at least one of the D-plus and D-minus pads, and configuring the IC in the ISO mode or the USB mode depending on the result. Once the IC is configured in a particular mode, it will operate in only that mode until the next power-on reset sequence.

Abstract: A system and method regulates an alternator charging system and includes a memory for storing and regulating voltages used at specific temperatures for the specific alternator charging system requirements of an alternator. A circuit generates a digital signal indicative of both temperature of a battery supplied by the alternator charging system and the charging system voltage. A digital comparator receives the digital signal and compares the digital signal with the regulating voltage stored within the memory for the specific temperature that is indicative of the temperature of the battery supplied by the alternator charging system to generate a regulator control signal.

Abstract: A system and method regulates an alternator and includes a circuit for digitally generating a sawtooth waveform. An error amplifier circuit generates a divided down and error amplified alternator system voltage. A comparator circuit receives and compares to each other the digitally generated sawtooth waveform and the error amplified alternator system voltage and has an output to produce an alternator field input signal used for driving the field of an alternator.

Abstract: An Ethernet device and the method for applying back pressure within an Ethernet communication network comprising the steps of asserting a back pressure pin of a media access control unit associated with a network communications port of an Ethernet device. In response to asserting the back pressure pin, only the back pressure continuous preamble of a packet is transmitted without a start-of-frame delimiter onto the network.

Abstract: An LED driver circuit and method are disclosed where an array of light emitting diodes have a transistor connected to each respective array of light emitting diodes. A PWM controller has an input for receiving a voltage reference and an output connected to selected transistors for driving selected transistors and setting a PWM duty cycle for the selected arrays of light emitting diodes to determine the brightness of selected light emitting diodes. An oscillator is connected to the PWM controller for driving the PWM controller.

Abstract: A method and network device are disclosed using a look-ahead watermark in a FIFO memory. In accordance with the present invention, a watermark interrupt is generated from a FIFO memory when data in the FIFO memory has crossed a watermark threshold. A data burst is transferred through a direct memory access unit to the FIFO memory. A look-ahead watermark flag is checked at the FIFO memory to determine if sufficient memory space exists inside the FIFO memory for an additional data burst, which is transferred through the direct memory access unit to the FIFO memory when the look-ahead watermark flag indicates that sufficient memory space is available.

Abstract: A method and system of controlling the transfer of data arranged in frames between a host and network device, such as an HDLC controller, having a shared system memory is disclosed. A frame is received within frame data buffers of the shared system memory. A single frame can span more than three frame data buffers. A descriptor ring has respective descriptors that describe and point to a respective frame data buffer and ownership by either the host or device. The descriptors for an associated frame data buffer that received a frame are placed together to form a descriptor chain having first and last descriptors. Only the first and last descriptors are updated within the descriptor chain to grant ownership of first and last descriptors and any intermediate descriptors to a desired host or device to enhance bus utilization.

Abstract: A method and apparatus for controlling data flow of data communications in a network are provided. A method preferably includes dynamically varying a minimum frame slot number, transmitting at least bytes of data from a frame of data of a slot, and determining the end of the frame of data. The method also preferably includes determining that the number of bytes of data within the frame is less than the current minimum frame slot number and transmitting flag bytes within the slot until the combination of the number of bytes and flag bytes equals the current minimum frame slot number. An apparatus preferably includes a transmitter for transmitting at least bytes of frames of data of a data slot, a byte counter responsive to the transmitter for counting the number of bytes in a frame of transmitted data, and a flag counter responsive to the transmitter for counting the number of flag bytes transmitted within a frame of transmitted data.

Abstract: An integrated oscillator and associated methods are provided for providing clock signals. The integrated oscillator preferably includes a micro-mechanical oscillating circuit for providing an oscillating clock signal. The micro-mechanical oscillating circuit preferably includes a support layer, a fixed layer positioned on a support layer, remaining portions of a sacrificial layer positioned only on portions of the fixed layer, and an oscillating layer positioned on the remaining portions of the sacrificial layer, overlying the fixed layer in spaced relation therefrom, and extending lengthwise generally transverse to a predetermined direction for defining a released beam for oscillating at a predetermined frequency. The spaced relation is preferably formed by removal of unwanted portions of the sacrificial layer.

Abstract: An integrated circuit and method are provided for sensing activity such as acceleration in a predetermined direction. The integrated released beam sensor preferably includes a switch detecting circuit region and a sensor switching region connected to and positioned adjacent the switch detecting circuit region. The sensor switching region preferably includes a fixed contact layer, remaining portions of a sacrificial layer on the fixed contact layer, and a floating contact on the remaining portions of the sacrificial layer and having only portions thereof directly overlying the fixed contact layer and in spaced relation therefrom in a normally open position and extending lengthwise generally transverse to the predetermined direction so that the floating contact contacts the fixed contact layer responsive to acceleration in the predetermined direction. The floating contact is preferably a released beam which is released by opening a window or removing unwanted portions of the sacrificial layer.

Abstract: An apparatus communicates over a communications channel and has reduced undesired local echo. The transmitter generates a transmit signal to the communications channel in a frequency band outside a voice frequency band. A receiver receives signals from the communications channel within or outside the voice frequency band, and is susceptible to undesired local echo from the transmit signal. In one method, a programmable scaler is connected to the transmitter and generates a scaled replica of the transmit signal based upon a scaled control signal. The receiver is connected to the scaler and reduces the undesired local echo by subtraction of a scaled replica of the transmit signal. An echo reducing circuit senses the received signal power and generates the scaled control signal based upon the received signal power to thereby reduce the undesired local echo In a second method, an estimate of the transfer function from the transmitter digital-to-analog converter to the input of a cancellor is developed.

Abstract: An integrated circuit and method are provided for sensing activity such as temperature variations in a surrounding environment. The integrated released beam sensor preferably includes a switch detecting circuit region and a sensor switching region connected to the switch detecting circuit region. The sensor switching region preferably includes a fixed contact layer, a sacrificial layer on the fixed contact layer, and a floating contact on the sacrificial layer and having portions thereof overlying the fixed contact layer in spaced relation therefrom in an open switch position and extending lengthwise generally transverse to a predetermined direction. The floating contact preferably includes at least two layers of material. Each of the at least two layers have a different thermal expansion coefficient so that the floating contact displaces in the predetermined direction responsive to a predetermined temperature variation so as to contact the fixed contact layer and thereby form a closed switch position.

Abstract: An AC and DC input power supply includes an AC power supply circuit and an AC input for receiving a range of AC input voltages. A rectifier circuit is connected to the AC input. An isolation output transformer has first and second primary winding terminals and a low voltage winding section for connecting to a DC voltage input that is lower than the range of the DC voltage that is rectified from the range of AC input voltages. The rectifier circuit is connected to the first primary winding terminal of the isolation output transformer. A transistor is connected to the second primary winding terminal of the isolation output transformer. The DC power supply circuit includes a DC input that is selectably connectable between the first primary winding terminal when the voltage input to the DC input connector is a nominal DC voltage that is within the range of the DC bulk voltage and the low voltage winding section when the voltage input to the DC input is lower than the range of the DC bulk voltage.

Abstract: A current bias, current sense magneto-resistive preamplifier for a hard disk drive and related methods preferably includes an MR sensor responsive to a current bias for sensing a change in magnetic data flux and responsively providing a change in electrical resistance. A preamplifying circuit is preferably connected to the MR sensor for providing the current bias thereto and for amplifying a detected change in electrical resistance. The preamplifying circuit includes a sensor biasing circuit for providing the current bias to the MR sensor and an amplifying output circuit for providing an amplified output signal representative of the detected change in current bias to the MR sensor. The sensor biasing circuit preferably includes a current source, a first amplifying circuit connected to the MR sensor for sensing the change in electrical resistance therefrom, and a second amplifying circuit having a first input connected to the first amplifying circuit and a second input connected to the current source.

Abstract: An integrated oscillator and associated methods are provided for providing clock signals. The integrated oscillator preferably includes a micro-mechanical oscillating circuit for providing an oscillating clock signal. The micro-mechanical oscillating circuit preferably includes a support layer, a fixed layer positioned on a support layer, remaining portions of a sacrificial layer positioned only on portions of the fixed layer, and an oscillating layer positioned on the remaining portions of the sacrificial layer, overlying the fixed layer in spaced relation therefrom, and extending lengthwise generally transverse to a predetermined direction for defining a released beam for oscillating at a predetermined frequency. The spaced relation is preferably formed by removal of unwanted portions of the sacrificial layer.

Abstract: A temperature compensated clock and method of clocking systems are provided. The clock preferably has an oscillator for generating an oscillating waveform signal at a preselected frequency and a frequency divider responsive to the oscillator for dividing the frequency of the oscillating waveform signal. A temperature monitoring circuit is positioned responsive to a voltage input signal independent of temperature and a voltage input signal proportional to temperature for monitoring temperature variations. A temperature compensating circuit, preferably including a programmable scaling circuit, is responsive to the frequency divider and the temperature monitoring circuit for scaling the divided frequency of the generated waveform and thereby advantageously produces a temperature compensated output timing signal.

Abstract: A method of forming an isolation region in an integrated circuit and an integrated circuit formed thereby. A method preferably includes forming at least one trench in a semiconductor substrate, forming an insulation layer of material in the at least one trench and on peripheral regions of the at least one trench of the semiconductor substrate, forming a sacrificial layer of material on the insulation layer having a different polishing rate than the insulation layer, and polishing the layer having the different polishing rate and portions of the insulation layer so that the sacrificial layer having the different polishing rate and portions of the insulation layer are removed, so that other portions of the insulation layer remain in the at least one trench of the substrate, and so that the upper surface of the at least one trench and the peripheral regions thereof in combination provide a substantially planar surface.

Abstract: An integrated circuit and associated method for switching from a power supply to a battery are provided. The integrated circuit preferably includes a memory circuit responsive to an external power supply and to a battery for storing data therein and a sleep mode latching circuit connected to the memory circuit for latching the memory circuit in a reduced power sleep mode condition so as to reduce power usage of a battery and a non-sleep mode operating condition so as to allow normal operation of the memory circuit by a power supply. The integrated circuit preferably also includes a sleep mode latch locking circuit connected to the sleep mode latching circuit and the memory circuit and responsive to a power supply for locking the sleep mode latching circuit in the non-sleep mode operating condition when power supplied from the power supply falls below a predetermined threshold so that the memory circuit is inhibited from inadvertently entering the reduced power sleep mode condition.

Abstract: An integrated circuit and method are provided for sensing activity such as acceleration in a predetermined direction of movement. The integrated released beam sensor preferably includes a switch detecting circuit region and a sensor switching region connected to and positioned adjacent the switch detecting circuit region. The sensor switching region preferably includes a plurality of floating contacts positioned adjacent and lengthwise extending outwardly from said switch detecting circuit region for defining a plurality of released beams so that each of said plurality of released beams displaces in a predetermined direction responsive to acceleration. The plurality of released beams preferably includes at least two released beams lengthwise extending outwardly from the switch detecting circuit region to different predetermined lengths and at least two released beams lengthwise extending outwardly from the switch detecting circuit region to substantially the same predetermined lengths.

Abstract: A method is provided for a planar surface of a semiconductor integrated circuit, and an integrated circuit formed according to the same. A conductive layer is formed over a substrate. A silicon nitride layer is formed over the conductive layer. A photoresist layer is then formed and patterned over the silicon nitride layer. The silicon nitride layer and the conductive layer are etched to form an opening exposing a portion of the substrate. The photoresist layer is then removed. The exposed substrate and a portion of the conductive layer exposed along the sidewalls in the opening are oxidized. An planarizing insulating layer such as spin-on-glass is formed over the silicon nitride layer and in the opening. The insulating layer is etched back to expose the silicon nitride wherein an upper surface of the insulating layer is level with an upper surface of the conductive layer. The silicon nitride layer is then removed. A planar silicide layer is then formed over the conductive layer.