Abstract: An impedance calibration circuit for impedance matching between a semiconductor memory device and an external device includes a driving circuit and a comparing circuit. The driving circuit has a plurality of internal resistances, with one or more of the internal resistances being a variable resistance. The driving circuit compares the impedance of the internal resistances to the input/output impedance of the external device in order to provide a calibration voltage. The comparing circuit compares the calibration voltage to a reference voltage and provides a code signal for calibrating the impedance corresponding to output data with the input/output impedance of the external device. The impedance calibration circuit calibrates an impedance mismatch between the impedance calibration circuit and a data input/output driver by adjusting the impedance of the impedance calibration circuit through the variable resistance.

Abstract: A security circuit includes an electrical fuse read only memory (ROM) including a plurality of electrical fuse units. The electrical fuse units are arranged to correspond to bit values of an initial security key before the electrical fuse ROM is programmed.

Abstract: A semiconductor integrated circuit capable of maintaining characteristics of transistors in a circuit including a plurality of cascade connected transistors. The circuit includes an inverter which has a series connection of P-MOS transistors and a pair of N-MOS transistors. The P-MOS transistor is connected to a high potential source VH and the N-MOS transistor is connected to a low potential source VL. The gate of each MOS transistor is connected to an input signal line. The inverter circuit further includes a P-MOS transistor connected between a node and input signal line, and an N-MOS transistor connected between a node of the N-MOS transistors and the input signal line. The gates of the P-MOS transistor and the N-MOS transistor are connected to an output signal line of the inverter circuit.

Abstract: A programmable interconnect network for an array of logic cells. Said interconnect network has a plurality of switch boxes being connected in a tree structure and providing connections to its logic cells, switch boxes located at the lowest level of the tree structure are connected to logic cells; said interconnect network also has peripheral switch boxes, of which at least one is connected to an external logic. Also, an integrated circuit comprising an FP array of logic cells connected by the said programmable interconnect network and a mask programmable (MP) logic array.

Abstract: Electronic circuitry and techniques are disclosed for controlling one or more timing parameters associated with a circuit that converts a signal of a first type to a signal of a second type. For example, the converter circuit may convert a differential digital logic signal, such as a current mode logic (CML) signal, to a complementary metal oxide semiconductor (CMOS) signal. For example, apparatus for converting a first type of signal to a second type of signal comprises the following circuitry. First circuitry is configured for generating a first pair of CMOS signals in response to a differential digital logic signal, the first pair of CMOS signals comprising a first CMOS signal having a first polarity and a second CMOS signal having a second polarity.

Abstract: DPA-resistant logic circuits and routing are described. An architecture and methodology are suitable for integration in a common automated EDA design tool flow. The architecture and design methodology can be used in logic circuits, gate arrays, FPGAs, cryptographic processors, etc. In one embodiment, the implementation details of how to create a secure encryption module can be hidden from the designer. The designer is thus, able to write the code for the design of DPA-resistant logic circuits using the same design techniques used for conventional logic circuits. Contrary to other complicated DPA -blocking techniques, the designer does not need specialized knowledge and understanding of the methodology. In one embodiment, the automated design flow generates a secure design from a Verilog or VHDL netlist. The resulting encryption module has a relatively constant power consumption that does not depend on the input signals and is thus relatively independent of which logic operations are performed.

Abstract: A method of calibrating longitudinal balance for a subscriber line interface circuit includes providing a first and a second driver of a differential driver pair for driving a subscriber line. An output of each of the first and second drivers is coupled to a common output. The common output is coupled to an input of the first driver. The gain of at least one of the first and second drivers is adjusted until a calibration signal (V1) present at the input of the first driver is substantially the same as a calibration signal (V2) present at the input of the second driver.

Abstract: A configurable circuit of the present invention includes a plurality of logic blocks (4), and a programmable bus which can program connections of plurality of logic blocks (4). The programmable bus includes a plurality of wires (11—x) arranged for each of signal transmission ranges corresponding to plurality of logic blocks (4), direct wire connection switch (711—x) which can program whether to directly connect or disconnect the wires between the adjacent signal transmission ranges, input selector (30—x) which can program a connection with any one of the plurality of wires, and programmable switch (40—x) which can program whether to make a connection with the wire corresponding to the adjacent signal transmission range for each of the plurality of wires. A plurality of programmable switches (40—x) are arranged for at least one of plurality of logic blocks (4).

Abstract: An antifuse circuit includes a terminal, an antifuse, and a select transistor. The antifuse is coupled to the terminal and has an associated program voltage. The select transistor is coupled to the antifuse and has a gate terminal coupled to receive a first select signal. The select transistor operates in a snapback mode of operation in response to an assertion of the first select signal and the program voltage at the terminal.

Abstract: Embodiments of a memory controller are described. This memory controller communicates signals to a memory device via a signal line, which can be a data signal line or a command/address signal line. Termination of the signal line is divided between an external impedance outside of the memory controller and an internal impedance within the memory controller. The memory controller does not activate the external impedance prior to communicating the signals and, therefore, does not deactivate the external impedance after communicating the signals. The internal impedance of the memory controller can be enabled or disabled in order to reduce interface power consumption. Moreover, the internal impedance may be implemented using a passive component, an active component or both. For example, the internal impedance may include either or both an on-die termination and at least one driver.

Abstract: An impedance matching device includes a calibration circuit configured to generate impedance calibration codes for modification of impedance; a code modification unit configured to modify the impedance calibration codes according to impedance setting information and output modified impedance calibration codes; and a termination impedance unit configured to terminate an interface node with impedance determined according to the modified impedance calibration codes.

Abstract: This invention relates to mixed signal integrated circuits, that is, integrated circuits comprising both analog and digital circuitry. More particularly, it concerns reduction of noise in such a device. When a digital circuit is included in the same integrated circuit device as an analog circuit, the digital circuit may be an additional source of a considerable amount of noise. This results in cross-talk, electrical interference and signal distortion imposed on the analog signals. The invention provides an integrated circuit comprising analog circuitry (26) and digital circuitry (29, 30) wherein the digital circuitry includes an ASM (30). An ASM does not require a clock signal. Its operation is triggered by appropriate input conditions, but in contrast to an SSM it is idle when there in no change in its inputs, lowering the level of noise generated by the digital circuitry.

Abstract: An integrated circuit with a configurable portion, such as an input/output port, that can be placed in a default configuration prior to actual configuration of the integrated circuit. An external terminal that serves as an output during normal operation is coupled, after power-on of the integrated circuit, to a comparator that senses the voltage level at that external terminal. If the external terminal is at a particular level, a multiplexer is controlled to ignore the state of the normal configuration memory, and to place the configurable input/output port into a default protocol.

Abstract: Circuits, methods, and apparatus that isolate an input register from spurious transitions on a DQS signal. One example receives an enable signal from a core. A logic circuit, which may be referred to as a one-half period circuit, shortens enable pulses at their front end by one-half a period. The shortened enable signal is passed to a storage element such as a register. Active pulses of the shortened enable signal clear the register, which provides a control signal closing a switch, such as an AND gate. The switch passes the DQS signal to the input register when closed and isolates the input register from the DQS signal when open. The shortened enable signal prevents the switch from opening early and passing spurious transitions on the DQS signal, for example during back-to-back non-consecutive read cycles.

Abstract: It is disclosed a combinatorial logic circuit comprising a first logic block (B1) coupled to a supply terminal (VDD) via a first resistor means (RI) and via a second resistor means (R2) for receiving respective first and second supply currents (111, 112). The circuit further comprises a second logic block (B2) coupled to the supply terminal (VDD) via the first resistor means (R1) and via the second resistor means (R2) for receiving respective third and fourth supply currents (122, 121). A first output terminal (Q?) coupled to the first block (B1) and to the first resistor means (R1). A second output terminal (Q+) coupled to the second logic block (B2) and to the second resistor means (R2). A first current source (I0) coupled to at least one of the first output terminal (Q?) and/or second output terminal (Q+) for providing a first supply current (I1) through the first resistor means (R1), which is substantially equal to a second supply current (I2) through the second resistor means (R2).

Abstract: Disclosed is a level shift circuit that includes a first level shifter which is connected between an output terminal and a first power supply terminal that supplies a first voltage and sets the output terminal to a level of the first voltage when an input signal received at an input terminal assumes a first value; a second level shifter which is connected between the output terminal and a second power supply terminal that supplies a second voltage and sets the output terminal to a level of the second voltage when the input signal assumes a complementary value of the first value; and a feedback control unit that performs control of deactivating the first level shifter during a predetermined time interval including a point of time when the input signal is supplied when it is detected that the output terminal immediately before the input signal is received at the input terminal assumes the first voltage level.

Abstract: The invention relates to an I/O buffer with twice the supply voltage tolerance using normal supply voltage devices. The I/O buffer of the invention includes a driver, a first level converter, a gate-controlled circuit and a dynamic source output stage. Signals of the I/O buffer are classified into a first voltage range and a second voltage range. The first voltage range is zero to the normal supply voltage, and the second voltage range is the normal supply voltage to twice the supply voltage. Therefore, the voltage between any two terminals of any of the transistors in the I/O buffer does not exceed the normal supply voltage so that the I/O buffer of the invention can transmit and receive signals with a voltage swing twice as high as the normal power supply voltage using normal supply voltage devices and without gate-oxide reliability problems.

Abstract: In one embodiment, a programmable logic device includes a plurality of configuration cells that store configuration data, wherein the programmable logic device is adapted to provide soft error upset (SEU) protection for the configuration cells that are reprogrammable. The programmable logic device may further include or alternatively provide hard coding and/or hard encoding of the configuration cells.

Abstract: A method and apparatus for a Gigabit Ethernet transceiver that has a Class-B amplifier in a main transmitter for higher efficiency and power handling capabilities. The output current of the main transmitter is produced by a reference voltage applied across a resistor, where the reference voltage generator, resistor and amplifier are fabricated on the same substrate, such that the output current is constant across process voltage and temperature. The transceiver also has a replica transmitter whose signal is used to cancel the main transmitter signal at the input of the receiver section of the transceiver. The replica transmitter is fabricated on the same substrate as the main transmitter, such that its output signal reflects non-linearities in the main transmitter across process voltage and temperature.

Abstract: A termination control circuit for a global input/output line includes a speed determination unit configured to output a termination enable signal which is activated in response to a frequency of an external clock signal and CAS latency information; and a pulse generation unit configured to output a driving signal for driving a termination circuit for the global input/output line in response to a termination control signal and the termination enable signal.