Abstract: An oscillator circuit (40, 60) has a comparator circuit (48, 68) and a monitor and control circuit (50, 80). The comparator (48, 68) provides a periodic output signal. The monitor and control circuit (50, 80) controls the voltage swing of the periodic output voltage in response to monitoring a periodic input voltage. A capacitor (52, 90) is coupled between the output terminal of the monitor and control circuit (50, 80) and input terminal of the comparator (48, 68) and is sized to set the oscillation frequency. The monitor and control circuit (50, 80) functions to limit the input voltage excursions without using an attenuation capacitor (16). Eliminating the attenuation capacitor (16) provides a smaller oscillator circuit having reduced power supply current spikes and which is easier to implement.

Abstract: A DMA controller has both a receiving portion and a sending portion and may be used in a modem or other data transmission context. The DMA controller is intended to provide to or receive from data samples on a bus that may or may not be available. For the case when the bus is available, samples of data are either sent to or received from proper memory locations. When the bus is not available, the number of the samples that are missed due to the bus not being available is stored. This count is then used to ensure that the samples that are provided or received when the bus becomes available are stored in or read from the proper location to provide the samples at the proper time. The locations in which the samples were lost are provided with predetermined values.

Abstract: A data processing system (20) is able to perform parameter-selectable prefetch instructions to prefetch data for a cache (38). When attempting to be backward compatible with previously written code, sometimes performing this instruction can result in attempting to prefetch redundant data by prefetching the same data twice. In order to prevent this, the parameters of the instruction are analyzed to determine if such redundant data will be prefetched. If so, then the parameters are altered to avoid prefetching redundant data. In some of the possibilities for the parameters of the instruction, the altering of the parameters requires significant circuitry so that an alternative approach is used. This alternative but slower approach, which can be used in the same system with the first approach, detects if the line of the cache that is currently being requested is the same as the previous request. If so, the current request is not executed.

Abstract: A memory (10) has a memory array (12), a charge pump (18), a voltage regulator (20), a refresh control circuit (16), and a refresh counter (22). The charge pump (18) provides a substrate bias to the memory array (12). The voltage regulator (20) provides a pump enable signal for maintaining a voltage level of the substrate bias within upper and lower limits. The refresh control circuit (16) controls refresh operations. The refresh counter (22) is coupled to receive the pump enable signal, and in response, provides a refresh timing signal to the refresh control circuit (16) to control a refresh rate of the memory array (12). A programmable fuse circuit (26) is provided to program the refresh rate using the counter (22). The programmable fuse circuit (26) may be programmed during wafer probe testing or board level burn-in. A built-in self test (BIST) circuit (24) may be included to facilitate testing.

Abstract: A memory (10) includes a variable refresh control circuit (20) for controlling the refresh rate of a memory array (12)using a capacitor for data storage. In one embodiment, each test cell of a plurality of test memory cells (30, 32, 34, and 36) is refreshed at different rates. A monitor circuit (18) is provided for monitoring the stored logic state of each of the plurality of test memory cells, and in response, adjusting the refresh rate of the memory array (12). In another embodiment, a variable refresh control circuit (20′) includes a plurality of test memory cells (70, 72, 74, and 76) that are all refreshed at the same rate but each of the test memory cells (70, 72, 74, and 76) is implemented to have a different charge storage capacity than the other test memory cells. The monitor circuit (18) monitors the stored logic state of each of the plurality of test memory cells (70, 72, 74, and 76), and in response, adjusts a refresh rate of the memory array (12).

Abstract: A first-in, first-out (FIFO) memory system (10) includes first and second FIFOs (A and B). First and second multiplexers (12, 14) each have two input terminals for receiving data. An output terminal of the first multiplexer (12) is coupled to the first FIFO (A) and an output terminal of the second multiplexer (14) is coupled to the second FIFO (B). In response to the data being one data type, write control logic (90, 95, 100) is used to cause the data to be alternately written to the first and second FIFOs (A, B). In response to the data being a second data type, write control logic (90, 95, 100) is used to cause the data to be simultaneously written to the first and second FIFOs (A, B).

Abstract: A sense amplifier (1300, 1500) is provided for sensing the state of a toggling type magnetoresistive random access memory (MRAM) cell without using a reference. The sense amplifier (1300, 1500) employs a sample-and-hold circuit (1336, 1508) combined with a current-to-voltage converter (1301, 1501), gain circuit (1303), and cross-coupled latch (1305, 1503) to sense the state of a bit. The sense amplifier (1300, 1500), first senses and holds a first state of the cell. The cell is toggled to a second state. Then, the sense amplifier (1300, 1500) compares the first state to the second state to determine the first state of a toggling type memory cell.

Abstract: A debug module (20) is provided which allows a developer to capture three types of debug information. The three types of debug information are: change-of-flow addresses, CPU data, and current instruction addresses. The debug information is captured in an on-chip debug FIFO memory (30) during program development. The debug information is provided to an external host via a serial communication interface (14) for post-processing and analysis. Storing and retrieving program information in this way is useful in microcontrollers that do not provide external access to address and data bus signals.

Abstract: A memory (110) uses memory cells not intended for user programming referred to as ‘dummy’ cells (202, 206). When selected, the dummy cells provide a current that establishes a reference voltage substantially equal to one-half of voltage created in a bit line by a cell programmed to a one and a cell programed to a zero. The reference voltage is sensed and compared with a bit line voltage created when a memory cell is read. By time multiplexing either one dummy cell programmed to a logic one or two dummy cells per bit line programmed respectively to logic one and logic zero, the desired reference voltage is accurately created. Memories such as MRAM and Flash that may be is difficult to accurately sense due to cell processing variations are enhanced by the timed selective use of one or more dummy cells.

Abstract: A performance monitor system includes a core processor (115), a core processor associated device, such as a cache (123), and first logic, such as performance logic (127). The core processor (115) is operable to execute information. The core processor associated device provides a first signal (CACHE_PERF), which defines performance of the core processor associated device (123) during operation of the core processor (115). The first logic (127) is coupled to the core processor associated device (123) and monitors the first signal (CACHE_PERF) in response to a second signal (WPT0,1), which defines a match of user-settable attributes associated with the operation of the core processor (115).

Abstract: A MRAM toggle type memory cell is read by first providing a first signal representative of the initial state to a sense amplifier (1300, 1500). A resistance of the cell is temporarily changed by altering a magnetic polarization of the free layer of the cell. A second signal responsive to altering the resistance of the MRAM cell is provided to the sense amplifier (1300, 1500). The first signal is compared to the second signal to determine the state of the MRAM cell.

Abstract: An integrated circuit die includes an input/output (I/O) cell. The I/O cell includes active I/O circuitry in a substrate, a plurality of metal interconnect layers, an insulating layer, a first pad, and a second pad. The plurality of metal interconnect layers are formed over the substrate. The insulating layer is formed over the plurality of metal interconnect layers. The second pad is formed over the insulating layer and positioned directly over at least two metal structures in a final metal layer of the plurality of interconnect layers. The pad is selectively coupled to one of at least two metal structures by at least one opening in the insulating layer.

Abstract: A magnetoresistive random access memory (MRAM) has separate read and write paths. Switchable current mirrors, each having multiple series-connected stages, receive a common reference current. A timing circuit provides control signals to word and bit decoders and to the switchable current mirrors to selectively complete current paths through a predetermined write word line and a predetermined write bit line. Bit lines are connected together at a common end, and word lines are connected together at a common end. By precharging a common rail having multiple write bit lines connected together, the write noise immunity is improved and current spikes are minimized. Groups of bit lines may be connected via a metal option to adjust a transition time of a programming current.

Abstract: A method (100) to manufacture semiconductor reticles associated with a design uses an optical pattern correction (OPC) test pattern (104) in a first reticle frame and having subresolution features that will not resolve or appear on a resulting wafer. A first reticle is made (106) and critical parameters are extracted from the first reticle (108). The critical parameters are used to execute an OPC model (112) to generate a modified design. A production reticle is made from the modified design. The OPC test pattern is placed in a second reticle frame and a second reticle is manufactured. Critical parameters from the second reticle are compared with the critical parameters from the first reticle and must be within a predetermined tolerance or the reticle build process is modified until the tolerance is reached.

Abstract: A magnetoresistive random access memory (MRAM) has separate read and write paths. Switchable current mirrors, each having multiple series-connected stages, receive a common reference current. A timing circuit provides control signals to word and bit decoders and to the switchable current mirrors to selectively complete current paths through a predetermined write word line and a predetermined write bit line. Bit lines are connected together at a common end, and word lines are connected together at a common end. By precharging a common rail having multiple write bit lines connected together, the write noise immunity is improved and current spikes are minimized. Groups of bit lines may be connected via a metal option to adjust a transition time of a programming current.

Abstract: A multi-bit non-volatile memory device includes a charge storage layer (14) sandwiched between two insulating layers (12 and 16) formed on a semiconductor substrate (10). A thick oxide layer (18) is formed over the charge storage layer (14) and a minimum feature sized hole is etched in the thick oxide layer (18). An opening is formed in the thick oxide layer (18). Side-wall spacers (60) formed on the inside wall of the hole over the charge storage layer have a void (62) between them that is less than the minimum feature size. The side-wall spacers (60) function to mask portions of the charge storage layer (14), when the charge storage layer is etched away, to form the two separate charge storage regions (55 and 57) under the side-wall spacers (60). The device can be manufactured using only one mask step. Separating the charge storage regions prevents lateral conduction of charge in the nitride.

Abstract: An output buffer (100) contains a low voltage driver (110), a medium voltage driver (108), and a high voltage driver (106). When an output pad (112) is configured to operate between ground and the medium voltage, the low voltage driver (110) is first used during low-to-high transitions to drive the output pad (112) from ground to an intermediate voltage in a fast manner. After the intermediate voltage is obtained on the output pad (112), a detection circuit (111) will switch output pad control from the low voltage driver (110) to the medium voltage driver (108). The medium voltage driver (108) will drive the output pad (112) from the intermediate voltage to the final logic one output voltage. This two-stage low-to-high driving methodology ensures that there will be less delay time from input (DO) to the output pad (112).

Abstract: A magnetoresistive random access memory (MRAM) has separate read and write paths. Switchable current mirrors, each having multiple series-connected stages, receive a common reference current. A timing circuit provides control signals to word and bit decoders and to the switchable current mirrors to selectively complete current paths through a predetermined write word line and a predetermined write bit line. Bit lines are connected together at a common end, and word lines are connected together at a common end. By precharging a common rail having multiple write bit lines connected together, the write noise immunity is improved and current spikes are minimized. Groups of bit lines may be connected via a metal option to adjust a transition time of a programming current.

Abstract: A radio receiver (100) has an IF (intermediate frequency) filter (200) for dynamically adjusting its intermediate frequency. The filter (200) includes a filter bank (301), power/amplitude estimator circuits (308, 310, 312), and weighting circuits (314, 316, 318). The filter bank (301) generates sub-bands, each sub-band having a predetermined frequency range. The power/amplitude estimators (308, 310, 312) provide an estimated power/amplitude in each sub-band. A filter control (320) uses the power/amplitude estimates to determine a percentage of each sub-band signal that is permitted to be coupled a summation circuit (319). The summation circuit (319) sums the weighted sub-band signals to provide a filtered output signal to a demodulator (212).

Abstract: A lithographic reticle with subresolution features in the design-pattern is used to control critical dimensions in a semiconductor manufacturing process. After the location of design and processing features is determined, subresolution features are formed in areas devoid of design and processing features. The subresolution features can substantially fill all of the area devoid of design processing features or, instead, selectively fill portions of the area. In one embodiment, the width of the area devoid of design and processing features is less than two times the width of a feature. The presence of the subresolution features results in improved control of small dimensions of features in semiconductor processing, thereby increasing yield and device performance.