Abstract: A system and technique for detecting a device that requires power is implemented with a power detection station. The power detection system includes a detector having an output and a return which are coupled together by the device when the device requires power. The detector includes a word generator for generating test pulses for transmission to the device via the detector output, and a comparator for comparing the detector output with the detector return. The power detection station has a wide variety of applications, including by way of example, a switch or hub.

Abstract: A data switch for network communications includes at least one first data port interface which supports a plurality of data ports which transmit and receive data at a first data rate. At least one second data port interface is provided; the at least one second data port interface supports a plurality of data ports transmitting and receiving data at a second data rate. A CPU interface is provided, with the CPU interface configured to communicate with a CPU. An internal memory is provided, and communicates with the at least one first data port interface and the at least one second data port interface. A memory management unit is provided, and includes an external memory interface for communicating data from at least one of the first data port interface and the second data port interface and an external memory.

Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.

Abstract: A method and apparatus to ensure DLL locking at a minimum delay is provided. In one embodiment, a DLL circuit includes a phase detector, a counter, a programmable delay line, and a counter control circuit. Upon initialization of the DLL circuit, the counter control circuit is configured to cause the counter to count increment, regardless of the phase relationship between a reference clock signal and the output clock signal. The counter continues incrementing, thereby changing the phase relationship between the reference clock signal and the output clock signal by adjusting the delay of the programmable delay line. This eventually results in a phase lock between the reference clock signal and the output clock signal at a minimum delay. Once the DLL achieves a phase lock between the reference clock signal and the output clock signal, the counter increments or decrements its count in order to maintain or re-acquire a lock.

Abstract: In accordance with the present invention a data processing circuit includes a first data path for processing first data. The first data path includes a first data storage circuit. A second data path is provided for processing second data. The second data path includes a second data storage circuit. A multiplexer having a first input coupled to the first data path and a second input coupled to the second data path receives the stored values. The multiplexer includes a select input coupled to a clock signal. A delay circuit is configured to delay storage of the second data in the second data storage circuit, wherein the first data storage circuit stores the first data in response to receiving a first timing signal, and the second data storage circuit stores the second data in response to receiving a second timing signal.

Abstract: An FM radio receiver includes a low noise amplifier, down conversion mixing module, local oscillation module, bandpass filter, demodulation module, and a DC offset estimation module. The low noise amplifier, the down conversion mixing module, the bandpass filter, and the demodulation module are operably coupled to recapture data from a received a radio frequency (RF) signal. The local oscillation module is operably coupled to generate the local oscillation based on a reference oscillation and a DC offset correction signal. The DC offset estimation module is operably coupled to generate the DC offset correction signal based on a determined a DC offset. The DC offset estimation module determines the DC offset prior to compensation of the local oscillation, such as during a test sequence and/or during a preamble.

Abstract: The method and system of the present invention superimposes read and write operations by connecting the global bit lines that are not selected to the Vdd. As a result, the respective local sense amplifiers for the non-selected global bit lines will just read and refresh the respective memory cells. This new approach results in smaller local sense amplifiers and one global sense amplifiers for several memory cells (and local sense amplifiers).

Abstract: A radio receiver includes a low noise amplifier, intermediate frequency mixing stage, complex bandpass filter, a single analog to digital converter, a 1st digital mixing module, and a 2nd digital mixing module. The low noise amplifier is operably coupled to amplify a modulated radio frequency (RF) signal to produce an amplified modulated RF signal. The intermediate frequency mixing stage is operably coupled to mix the amplified modulated RF signal with a local oscillation to produce a modulated IF signal. The complex bandpass filter filters an I and Q component of the modulated IF signal to produce a filtered IF signal. The single analog to digital converter is operably coupled to convert the filtered IF signal into a digital IF signal. The 1st and 2nd mixing modules each receive the digital IF signal and mix the digital IF signal with an in-phase and quadrature digital local oscillation to produce a 1st baseband signal component and a 2nd baseband signal component.

Abstract: A system-on-chip (SOC) device or a random access memory (RAM) chip includes a RAM block. The RAM block includes memory cells, each of which has three transistors. Each memory cell is coupled to both a read bit line and a write bit line. A transparent continuous refresh mechanism has been implemented to read the content of a memory cell and re-write it back to the memory cell without disturbing the access (read/write) cycle, making refresh operations transparent to the system level. The continuous refresh mechanism includes a collision detection mechanism to prevent writing and reading the same memory cell at the same time.

Abstract: In a latch circuit having a bistable pair of cross connected transistors of a first polarity and a third transistor of a second polarity, a current signal greater than a bias current is received at a latch circuit port, amplified with the third transistor, and applied to the latch circuit port. This decreases the time in which the latch circuit port receiving the current signal greater than the bias current reaches a steady state voltage.

Abstract: The present invention relates to a multi-port register file memory or SRAM including a plurality of storage elements and other circuitry that operate synchronously or asynchronously. The storage elements are arranged in rows and columns and store data. Two read port pairs are coupled to each of the storage elements and a differential sensing device or circuit. The read port is coupled to the storage elements in an isolated manner, enabling a plurality of cells to be arranged in such rows and columns. The sensing device is adapted to sense a small voltage swing. A column mux circuit is coupled to each column and the sensing device. Performance is not degraded unusually as the power supply voltage is reduced due to bus drop or inductive effects.

Abstract: An integrated oscillator that may be used as a time clock includes circuitry that oscillates about an RC time constant, which RC time constant is adjustable to provide a desired frequency of oscillation. More specifically, the oscillator includes a capacitor array that has a plurality of capacitors coupled in parallel wherein each capacitor may be selectively included into the RC time constant or selectively excluded there from. Rather than setting the capacitance values to a desired capacitance value, a system for adjusting the time constant includes circuitry for measuring an output frequency and for comparing that to a certified frequency source wherein the time constant is adjusted by adding or removing capacitors from the capacitor array until the frequency of the internal clock matches an expected frequency.

Abstract: An agent, in response to a write to a shared block, is configured to initiate a read exclusive transaction on an interface on which the agent communicates. Additionally, the agent is configured to indicate, to a responding agent or agents on the interface, that a data transfer is not required from the responding agent or agents in response to the read exclusive transaction. In one embodiment, the agent indicates to the responding agents that a data transfer is not required in a response phase of the transaction. Specifically, the agent may respond in such a way that the agent indicates that it will provide the data (i.e. that the agent will provide the data to itself). For example, the agent may respond with an exclusive ownership indication. On the interface for such an embodiment, an exclusive ownership response may require that the agent having exclusive access respond with the data.

Abstract: A conditional clock buffer circuit includes a clock output and is coupled to receive a clock input and a condition signal. The conditional clock buffer circuit includes a first circuit coupled to receive the clock input and a second circuit coupled to receive the clock input and the condition signal. The first circuit is configured to generate a first state on the clock output responsive to a first phase of the clock input. The second circuit is configured to conditionally generate a second state on the clock output responsive to the condition signal during a first portion of a second phase of the clock input. In one implementation, one or more of the conditional clock buffer circuits may be included in a clock tree. The clock tree may also include one or more levels of buffering.

Abstract: A resonant oscillator circuit includes an active device and a resonator that causes the active device to oscillate at a resonant frequency of the resonator. The active device includes one or more transistors that are DC biased using one or more resistors. The bias resistors generate thermal noise that is proportional to the resistance value. An external inductor circuit is connected across the output terminals of the active device and in parallel with the resonator. The external inductor circuit short-out at least some of the thermal noise that is generated by the bias resistors, and thereby reduces the overall phase noise of the resonant oscillator.

Abstract: A method and apparatus for modulating a signal into a digital representation thereof includes processing that begins by integrating a difference between an input signal and an analog feedback signal to produce an integrated signal. The processing then continues by quantizing the integrated signal to produce a quantized signal. The processing continues by generating a spectral shaping signal to compensate for non-linearities of the analog feedback signal. The processing further continues by injecting the spectral shaping signal into the quantized signal to produce a spectrally adjusted quantized signal. The processing further continues by converting the spectrally adjusted quantized signal into the analog feedback signal.

Abstract: A digital IF demodulator receives and demodulates an analog IF input signal to produce a digital audio signal and a digital video signal. The digital IF demodulator includes an A/D converter, a first digital complex mixer, a second digital complex mixer, and various digital filters. The first digital complex mixer receives the output of the A/D converter and down-converts the output of the A/D converter to baseband. Additionally, the picture carrier is recovered from the output of the first digital complex mixer, and fed back to a direct digital synthesizer to control the tuning accuracy of the first digital complex mixer. More specifically, a feedback loop is formed to so that the picture carrier is down-converted to DC so as to control the tuning accuracy of the first digital complex mixer. The complex output of the first complex mixer is further processed using Nyquist filtering and other filtering to recover the digital video signal.

Abstract: A method of forwarding data in a network switch fabric is disclosed. An incoming data packet is received at a first port of the fabric and a first packet portion, less than a full packet length, is read to determine particular packet information including an opcode value. The opcode value allows the fabric to determine the packet type, such a a whether the packet is a broadcast packet, a unicast packet, a multicast packet, etc. Based on the opcode value read, a particular forwarding table of a plurality forwarding tables is read and an egress port bitmap is determined based on entries read from the particular forwarding table. The incoming data packet is then forwarded based on the egress port bitmap. In addition, the architecture of the switch fabric is also disclosed.

Abstract: Satellite communications are carried out using the Data Over Cable Interface Specification (DOCSIS). Satellite modems are notified of upstream channel congestion by inserting a congestion notification message in a medium access protocol (MAP) message for the upstream channel. Specifically, the congestion notification message is inserted in an unused field of the MAP message, such as the explicit congestion notification (ECN) field. The MAP message can also carry other characteristics of the upstream channel, including priority threshold, multicast access burst availability, and available bandwidth.

Abstract: A video and graphics system processes video data including both analog video, e.g., NTSC/PAL/SECAM/S-video, and digital video, e.g., MPEG-2 video in SDTV or HDTV format. The video and graphics system includes a video decoder, which is capable of concurrently decoding multiple SLICEs of MPEG-2 video data. The video decoder includes multiple row decoding engines for decoding the MPEG-2 video data. Each row decoding engine concurrently decodes two or more rows of the MPEG-2 video data. The row decoding engines have a pipelined architecture for concurrently decoding multiple rows of MPEG-2 video data. The video decoder may be integrated on an integrated circuit chip with other video and graphics system components such as transport processors for receiving one or more compressed data streams and for extracting video data, and a video compositor for blending processed video data with graphics.