Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric System Lsi Design Corporation

Renesas Electronics Corporation

Mitsubishi Denki Kabushiki

Mitsubishi Electric Systems Lsi Design Corporation

Akira Kitaguchi

Masaaki Matsuo

Makoto Hatakenaka

Michio Nakajima

Kiyoyuki Shiroshima

Takekazu Yamashita

Tsuyoshi Saitoh

Toshio Kumamoto

Takashi Okuda

Hideki Toki

Tatsuo Sengoku

Toshio Nakano

Kaoru Motonami

Nobuyuki Fujii

Masaharu Taniguchi

Tuyoshi Saitoh

Yuko Sudo

There is provided a technique for reducing the adverse effect of idle tones in the channels in a &#x394;&#x3a3;-type A/D converter including a plurality of channels for converting analog input signals into digital signals. The &#x394;&#x3a3;-type A/D converter includes an L channel for converting a left analog input signal into a digital signal and an R channel for converting a right analog input signal into a digital signal. Each of the L channel and the R channel includes a DC dither circuit for generating a DC addition voltage for shifting the frequency of an idle tone. In the L channel and the R channel, DC addition voltages generated by DC dither circuits are different from each other.

&#x394;&#x3a3;-type A/D converter

A semiconductor device test board solves a problem with conventional test boards in that test results obtained through a burn-in procedure could be identified only before the test board is taken out of a burn-in oven. Hence, conventional test boards required additional steps for checking the test results after removing the test boards from the burn-in oven. This extra step prevents the efficiency of the test from being improved. One embodiment of the present test board has indicator arms, each rotatably mounted on a pivot on the test board, for indicating, in response to a signal on a signal line, the test result of the semiconductor device associated with it. Each of the indicator arms maintains its rest position when no failure has occurred in the semiconductor device associated with it during the test. Each indicator arm changes its position if a failure has occurred in the semiconductor device during the test, and retains one of the two positions until after the test board is taken out of the burn-in oven. Thus, the test result can be determined after taking out the test board from the burn-in oven.

Semiconductor device test board and method for evaluating semiconductor

A test circuit includes a writing unit that outputs m-bit data captured upon receipt of a clock signal, branches the m-bit data n identical m-bit data signals, and stores the n m-bit data signals in a memory device. A function determining unit reads the n m-bit data signals from the memory, compares one of the n m-bit data signals to an m-bit expected value, and determines coincidence or non-coincidence between the n m-bit data signal and an expected value.

Test circuit

A semiconductor device capable of solving a problem of a conventional semiconductor device in that a high density integration cannot be expected because each cell, which includes a pair of N and P wells disposed adjacently, requires a countermeasure against latchup individually. The high density integration prevents an effective countermeasure against latchup. The present semiconductor device arranges two cells, which are adjacent in the direction of an alignment of the N wells and P wells, in opposite directions so that two P wells (or two N wells) of the two adjacent cells are disposed successively, and includes an isolation layer extending across the two adjacent cells to enclose the two successively disposed P wells, thereby isolating the two P wells collectively from the substrate.

Field effect transistor array including doped two-cell isolation region

A semiconductor integrated circuit includes a fuse element located on an insulating layer. The surface of the insulating layer is substantially smooth. The insulating layer is located over a capacitor. Wiring is located on the insulation layer. The fuse element and the wiring include the same material.

Semiconductor integrated circuit including a capacitor and a fuse element

A semiconductor memory device includes two subcircuits each including a memory circuit, a semiconductor circuit, and a logical circuit. Connection pads are divided into only two parallel rows located along the outer periphery of the semiconductor memory device. Each of the pads may include a probe region against which a probe is pressed for testing the semiconductor memory circuit, and a wire region to which a wire is connected upon packaging.

Semiconductor memory device

A semiconductor memory device includes memory elements, each maintaining memory contents within a period of time during which a refresh operation is repeated, and a refresh request circuit for making a refresh request. The semiconductor memory device includes refreshing circuits each of which, in response to a refresh request from the refresh request circuit, performs a refresh operation on a different number of memory elements at the same time, and a selecting circuit for selecting one refreshing circuit from among the refreshing circuits according to the number of memory elements included in the semiconductor memory device. The refresh request circuit can change the interval at which it makes a refresh request.

Semiconductor memory device and method of refreshing semiconductor

Disclosed is a semiconductor integrated circuit which can be tested with a high-speed clock of actual operation level or more, even if a relatively low-priced IC tester which is not capable of supplying high-speed clocks is employed, and a method of testing the same. An exclusive OR gate (2) of the semiconductor integrated circuit receives the first test clock (TCLK1) through the first test clock input pin (P1) into the first input and the second test clock (TCLK2) through the second test clock input pin (P2) into the second input, to output a high-speed clock (SCLK) resulting from the test clocks to an A input of a selector (3). Thus, the semiconductor interacted circuit internally generates the high-speed clock having higher frequency than that of the test clock to operate an internal circuit, thereby being tested with clock frequency of actual operation level or more even by means of the relatively low-priced IC tester.

Growing community of inventors

Tokyo, Japan

Akira Kitaguchi