Abstract: The apparatus includes a diode laser and a current source interconnected with the diode laser. Two independent circuits in the current source are configured to limit current flowing through the diode laser. A first current limiter circuit configured to limit a current output from the current source to an anode of the diode laser, and an independent second current limiter circuit configured to limit a current return from a cathode of the diode laser to the current source so that laser output power does not exceed a specified maximum regardless of a single fault in either the first or second current limiter circuits.

Abstract: One embodiment relates to an optical navigation apparatus which provides fault-tolerant limitation of laser output power. The apparatus includes a diode laser and a current source interconnected with the diode laser. Two independent circuits in the current source are configured to limit current flowing through the diode laser. Another embodiment relates to a method of providing fault-tolerant limitation of laser output power in an optical navigation apparatus. A first digital current limit value is converted to a first analog signal, and the first analog signal is used to limit an electrical current from a power supply connection to an anode of a diode laser. A second digital current limit value is converted to a second analog signal, and the second analog signal is used to limit an electrical current from a cathode of the diode laser to a ground connection. Other embodiments are also disclosed.

Abstract: A memory array including a conductive line adapted to simultaneously conduct current in at least two distinct directions relative and adjacent to a magnetic junction is provided. In some embodiments, one of the distinct directions may be substantially aligned with an elongated dimension of the magnetic junction, while another of the distinct directions may be substantially aligned with a shortened dimension of the magnetic junction. In yet other embodiments, at least one of the distinct directions may be aligned at an angle between approximately 0 degrees and approximately 90 degrees relative to an elongated dimension of the magnetic junction. In either case, a memory array is provided which includes a contiguous conductive line having a first portion arranged above a magnetic junction of the memory array and a second portion arranged below the magnetic junction. In addition, a method for operating such a magnetic memory array is provided.

Abstract: A memory circuit which is adapted to identify memory cells within a first time interval for a write operation of the circuit and identify the memory cells within a second time interval for a read operation of the circuit is provided. In some cases, the memory circuit may include an address path which includes a different circuit path for the read operations than for the write operations of the circuit. In addition, the memory circuit may include a means for intentionally delaying the identification of the memory cells for the write operation of the circuit. In some cases, the memory circuit may further include a means for intentionally delaying the identification of memory cells for the read operation of the circuit. Alternatively, the memory circuit may be absent a means for intentionally delaying the identification of memory cells for the read operation of the circuit.

Abstract: A circuit is provided herein, which is adapted to supply different current magnitudes along opposing directions of a conductive line. Such a circuit may be particularly beneficial in compensating for the effects of unintentional magnetic coupling within MRAM devices. In addition, a method is provided herein for configuring a device having a magnetic memory array, which receives a first current magnitude along one direction and a substantially different current magnitude along an opposite direction of the magnetic memory array. Furthermore, a method is provided herein which assigns tunable current magnitudes for write operations along conductive lines of a memory circuit. Such tunable writing currents advantageously increase the write selectivity of the memory circuit. More specifically, the tunable writing currents compensate for ferromagnetic and antiferromagnetic coupling within magnetic memory cells caused by uneven surface topology and non-zero total magnetic moments, respectively.

Abstract: An integrated circuit device includes an input circuit; logic circuitry coupled to the input circuit; an output circuit coupled to the logic circuitry; and a select circuit coupled to the input circuit, output circuit and logic circuitry. The select circuit generates a select signal that causes the input circuit, output circuit and logic circuit to operate according to a first state or a second state. The output buffer is configured to receive the select signal which selects output buffer operation at the first state or the second state. The output buffer is also configured to maintain a constant slew rate while operating in either the first or second state.

Abstract: A memory array is provided that includes a conductive line adapted to induce a magnetic field around less than all of the magnetic memory junctions arranged along a row or a column of the array. In some cases, the conductive line may be adapted to induce a magnetic field around more than two magnetic memory cell junctions. Alternatively, the conductive line may be adapted to induce a magnetic field around no more than two magnetic memory cell junctions. In either case, the conductive line may include a first portion vertically aligned with one of a plurality of magnetic memory cell junctions and a second portion vertically aligned with another of the plurality of magnetic memory cell junctions. In some embodiments, the second portion may be positioned such that a direction of current flow through the second portion is different than a direction of current flow through the first portion.

Abstract: A random access memory with a read port, a write port, a read/write control signal configured to control data transfer operations at the read port and/or the write port on both rising and falling transitions, and a first random access memory array configured to store and/or retrieve data at a first random address in the first random access memory array defined by one or more signals on a write address bus and/or a read address bus. One preferred embodiment further includes a write data register storing or latching data in response to a first transition of the read/write control signal, and the array storing data in response to a second transition of the read/write control signal. Other preferred embodiments further include an n·m-bits-wide input data bus coupling a set of data inputs to the write data register, and/or an n·m-bits-wide output data bus coupling the read data register to a set of data outputs, where n and m are each independently an integer >2.

Abstract: A random access memory with a data input bus, a data output bus, a random access memory array configured to transfer data to random write addresses and from random read addresses in the random access memory array, an address bus providing the random read addresses and the random write addresses, and a first periodic signal configured to control data transfer operations (i) to the random access memory array in response to a first transition of the periodic signal and (ii) from the random access memory array in response to a second transition of the periodic signal, wherein the second transition of the periodic signal is complementary to the first transition of the periodic signal. One preferred embodiment further includes circuitry operable to write data into and read data from the random access memory array. Other preferred embodiments further include a write data register and/or a read data register. In a further embodiment, each of the data input bus and the data output bus is unidirectional.

Abstract: A random access memory with a data input bus, a data output bus, a random access memory array configured to transfer data to random write addresses and from random read addresses in the random access memory array, an address bus providing the random read addresses and the random write addresses, and a first periodic signal configured to control data transfer operations (i) to the random access memory array in response to a first transition of the periodic signal and (ii) from the random access memory array in response to a second transition of the periodic signal, wherein the second transition of the periodic signal is complementary to the first transition of the periodic signal. One preferred embodiment further includes circuitry operable to write data into and read data from the random access memory array. Other preferred embodiments further include a write data register and/or a read data register. In a further embodiment, each of the data input bus and the data output bus is unidirectional.

Abstract: An integrated circuit device includes an input circuit; logic circuitry coupled to the input circuit; an output circuit coupled to the logic circuitry; and a select circuit coupled to the input circuit, output circuit and logic circuitry. The select circuit generates a select signal that causes the input circuit, output circuit and logic circuit to operate according to a first state or a second state. The output buffer is configured to receive the select signal which selects output buffer operation at the first state or the second state. The output buffer is also configured to maintain a constant slew rate while operating in either the first or second state.

Abstract: A semiconductor (preferably a CMOS) device having one or more latch-up inhibitor diffusion regions. The latch-up inhibitor regions are adjacent to complementary P-channel and N-channel transistors, and typically function to inhibit or prevent latch-up, without increasing the die size of the device.

Abstract: A random access memory with a read port, a write port, a read/write control signal configured to control data transfer operations at the read port and/or the write port on both rising and falling transitions, and a first random access memory array configured to store and/or retrieve data at a first random address in the first random access memory array defined by one or more signals on a write address bus and/or a read address bus. One preferred embodiment further includes a write data register storing or latching data in response to a first transition of the read/write control signal, and the array storing data in response to a second transition of the read/write control signal. Other preferred embodiments further include an n.m-bits-wide input data bus coupling a set of data inputs to the write data register, and/or an n.m-bits-wide output data bus coupling the read data register to a set of data outputs, where n and m are each independently an integer >2.

Abstract: A circuit including an address bus providing random addresses for a random access memory array, and a register configured to receive, store or transfer (i) a first random address from the address bus in response to a first periodic signal transition and (ii) a second random address from the address bus in response to a second periodic signal transition, wherein the first and second periodic signal transitions occur within a single periodic signal cycle, and are preferably complementary to each other.

Abstract: A circuit for delaying a signal. The circuit includes a scan register, a logic circuit, and a programmable delay circuit. The scan register stores scan data and the logic circuit selectively decodes the scan data. The programmable delay circuit is coupled to the logic circuit and delays a signal a programmable amount of time in response to the decoded scan data.

Abstract: A random access memory with a read port, a write port, a read/write control signal configured to control data transfer operations at the read port and/or the write port on both rising and falling transitions, and a first random access memory array configured to store and/or retrieve data at a first random address in the first random access memory array defined by one or more signals on a write address bus and/or a read address bus. One preferred embodiment further includes a write data register storing or latching data in response to a first transition of the read/write control signal, and the array storing data in response to a second transition of the read/write control signal. Other preferred embodiments further include an n·m-bits-wide input data bus coupling a set of data inputs to the write data register, and/or an n·m-bits-wide output data bus coupling the read data register to a set of data outputs, where n and m are each independently an integer >2.

Abstract: A random access memory with a data input bus, a data output bus, a random access memory array configured to transfer data to random write addresses and from random read addresses in the random access memory array, an address bus providing the random read addresses and the random write addresses, and a first periodic signal configured to control data transfer operations (i) to the random access memory array in response to a first transition of the periodic signal and (ii) from the random access memory array in response to a second transition of the periodic signal, wherein the second transition of the periodic signal is complementary to the first transition of the periodic signal. One preferred embodiment further includes circuitry operable to write data into and read data from the random access memory array. Other preferred embodiments further include a write data register and/or a read data register. In a further embodiment, each of the data input bus and the data output bus is unidirectional.

Abstract: A circuit for generating a pulse including a scan register having a first scan bit; first logic device receiving a first signal and generating a second signal; and a programmable delay circuit coupled to the scan register and the first logic device. The programmable delay circuit receives the second signal and generates a delayed second signal after a programmable period of time. The programmable period of time is determined by the first scan bit. The circuit also includes a logic circuit that recevies the second signal and the delayed second signal. The logic circuiit outputs the pulse having a pulse width proportional to the programmable period of time.

Abstract: A circuit including an address bus providing random addresses for a random access memory array, and a register configured to receive, store or transfer (i) a first random address from the address bus in response to a first periodic signal transition and (ii) a second random address from the address bus in response to a second periodic signal transition, wherein the first and second periodic signal transitions occur within a single periodic signal cycle, and are preferably complementary to each other.

Abstract: An integrated circuit including a first input for receiving a scan enable control signal and a second input for receiving a test mode control signal. The integrated circuit also includes a programmable scan circuit coupled to the first input and the second input. The programmable scan circuit configures the integrated device to operate in a default mode, a scan mode, or a test mode in response to the scan enable and test mode control signals.