Denso Corporation

Yoshinori Teshima

Hideaki Ishihara

Toshihiko Matsuoka

Katsutoyo Misawa

Naoki Ito

Yasuyuki Ishikawa

Akira Suzuki

Susumu Tsuruta

Kenji Yamada

Akimasa Niwa

Masahiro Kamiya

Hiroshi Fujii

Kyouichi Suzuki

Shuji Agatsuma

Masato Rinnai

Shinichi Noda

Chikara Kobayashi

Shinichiro Taguchi

Toshiharu Muramatsu

Kyoichi Suzuki

A signal processing apparatus for processing a periodic signal outputted from a signal source has a central processing unit and a task switch timer. The central processing unit performs multiple tasks including a signal processing task in parallel. In the signal processing task, the central processing unit starts to process the periodic signal after performing a synchronization processing to synchronize with the periodic signal, setting the task switch timer to a predetermined time upon completion of the synchronization processing, and enabling an interrupt to the central processing unit upon completion of the synchronization processing. The task switch timer disables the interrupt to the central processing unit immediately before expiring. The task switch timer outputs a task switch signal to the central processing unit when expiring, so that the central processing unit switches to the signal processing task.

Periodic signal processing apparatus

In a DPLL circuit, when the size of a data value which is output from a data latch circuit and should be naturally set in a 11-bit down-counter becomes equal to or more than 12 bits, an overflow preventing circuit substitutes the 11-bit data for the data value.

Frequency-multiplied clock signal output circuit

A communication system includes a master control unit, a plurality of slave control units, and buses connecting the master control unit and the slave control units for the asynchronous communication. When the master control unit starts the communication, each slave control unit transmits a plurality of data bits represented by whether the buses be driven to the master control unit in data transmission periods assigned to the slave control units based on a start of communication, and the master control unit drives the buses to insert a period for supplying power while data bits are being transmitted in the data transmission period. The slave control unit provides a non-driving period, which stops driving the buses, at an end of the data bit transmission period.

Communication system

A semiconductor integrated circuit includes: a package; semiconductor chips in the package including a signal terminal; and a wiring connecting signal terminals. One semiconductor chip is a test object chip including a probe terminal and a test object terminal. The probe terminal connects to an external terminal for testing the test object terminal. The test object chip further includes: a common wiring for connecting the probe terminal and the test object terminal; a first switch for connecting/disconnecting the probe terminal and the common wiring; a second switch for connecting/disconnecting the test object terminal and the common wiring; and a test signal interrupting element for interrupting the test signal to be inputted into an input circuit of the probe terminal.

Semiconductor integrated circuit having multiple semiconductor chips with signal terminals

During software development, a multichip module is used which encloses a target chip and a development chip in one package. A CPU of the development chip fetches instructions from a flash memory in the chip to execute them, and accesses RAM and peripheral circuits in the chip. For motor control circuits that exist only in the target chip, the CPU accesses them via serial communication. When the one-chip microcomputer operates alone, its CPU switches a switching circuit to a JTAG interface side to actuate a motor control circuit via internal serial communication.

Semiconductor integrated circuit device and microcomputer development supporting device

A single-chip microcomputer includes a logic circuit, a CPU and a flip-flop for synchronizing an interrupt-request signal, which is supplied by the logic circuit to the CPU, based on a clock signal. A multi-chip emulation apparatus comprises a peripheral evaluation chip, a CPU evaluation chip and a device, which are used for emulating functions of the logic circuit, the CPU and the flip-flop respectively. When the multi-chip emulation apparatus is used for emulating functions of the single-chip microcomputer in the development, the device for emulating functions of the flip-flop synchronizes the interrupt-request signal to absorb a delay time incurred by the interrupt-request signal due to a physical distance between the peripheral evaluation chip and the CPU evaluation chip so that an interrupt-handling timing in the emulation matches an interrupt-handling timing in the real operation of the single-chip microcomputer.

Microcomputer and emulation apparatus

In a clamp circuit device, reference voltages are set up by a series circuit of an FET, a resistor and an FET. Gate potentials of FETs are set up by performing addition and subtraction of these reference voltages and a reference voltage generated by a bandgap reference circuit, respectively. The clamp circuit device is constructed by connecting together a source of the one FET with its drain connected with the power supply and a source of the other FET with its drain connected with the ground to an input terminal of a control IC unit. Thus, an input voltage is clamped to [VVtp] when an excessive voltage of positive polarity is applied to an input terminal, and the input voltage is clamped to [VVtn] when an excessive voltage of negative polarity is applied.

Clamp circuit device

A multiprocessor system has a plurality of CPUs with respective local buses, and a memory which stores a plurality of programs to be executed by the CPUs and is connected to a common bus which can be accessed via the local buses, each local bus being connected to a CPU identification register which stores an identification value for identifying the corresponding CPU. When a program which is specific to a CPU is to be executed by that CPU, the corresponding identification value is read out from the identification register of the CPU and is judged, and branching to the appropriate program is performed based on the judgement result.

Multiprocessor system having a plurality of control programs stored in a continuous range of addresses of a common memory and having identification registers each corresponding to a processor and containing data used in deriving a starting address of a CPU-linked interrupt handler program to be executed by the corresponding processor

Integrated circuit device includes: a wiring; a clock signal output circuit including a ring oscillator; an internal circuit; an internal power supply generation circuit for supplying an electric power to the clock signal output circuit and to the internal circuit on the basis of a power supplied from an external circuit; and a capacitor connection terminal. The internal power supply generation circuit supplies the electric power to the ring oscillator through the wiring connecting between the internal power supply generation circuit and the capacitor connection terminal. The internal power supply generation circuit supplies the electric power to the internal circuit through the wiring connecting to the capacitor connection terminal.

Integrated circuit device having clock signal output circuit

The present invention relates to a clock control circuit apparatus including a first oscillation circuit for generating a first clock signal and a second oscillation circuit for generating a second clock signal and capable of, when the two clock signals are put to use, improving the reliability of oscillation operations thereof. In the clock control circuit apparatus, a sub-clock correction unit corrects an oscillation frequency of a sub-clock signal on the basis of a main clock signal, while a main clock monitoring unit monitors an oscillation state of the main clock signal on the basis of the sub-clock signal.

Clock control circuit for correcting frequency of second clock signal based on first clock signal and monitoring oscillation state of first clock signal based on second clock signal

A signal output section of a port sampling circuit periodically changes the output level of an output port based on a sampling period stored in a register which is set by CPU A data latch section of the port sampling circuit latches the data given to an input port based on a timing signal, with a starting point being set on a change point of the output level. A data register stores the latched data.

Growing community of inventors

Toyota, Japan

Yoshinori Teshima