Mitsubishi Denki Kabushiki Kaisha

Renesas Electronics Corporation

Renesas Technology Corp.

Kazuo Murakami

Yukio Kodama

Motoo Suwa

Toru Hayashi

Hideo Yoshida

Noboru Sekiguchi

Synchronization between command and address signals commonly coupled to a plurality of memory devices to be operated in parallel and a clock signal coupled to the memory devices is achieved, while suppressing an increase in the clock wiring length. A semiconductor device has a data processing device mounted on a wiring substrate and a plurality of memory devices accessed in parallel by the data processing device. The data processing device outputs the command and address signals as a first frequency from command and address terminals, and outputs a clock signal as a second frequency from a clock terminal. The second frequency is set to multiple times of the first frequency, and an output timing equal to or earlier than a cycle starting phase of the clock signal output from the clock terminal can be selected to the command and address signals output from the command and address terminals.

Semiconductor device and data processor

A semiconductor device includes an IC chip, a frame on which the IC chip is mounted, a conductive plate disposed beneath and spaced from the frame, a first external terminal and a second external terminal that electrically connect the IC chip, the frame, and the conductive plate, and a molding compound covering and encapsulating the IC chip, the frame, and the conductive plate.

Semiconductor device

When encoding data received by a dividing circuit and to be included in a CRC code word, the data is divided by a generator polynomial and remainder data resulting from the division is output from a plurality of parallel data output terminals of the dividing circuit. The remainder data is added to a CRC intrinsic value and '0' information in the adder to produce a sum. The sum is a CRC code for a CRC code word to be transmitted. When detecting code errors, data from a CRC code word is received by the dividing circuit, where the data is divided by the generator polynomial, and remainder data resulting from the division is output from the respective parallel data output terminals. The remainder data is added to the CRC intrinsic value and CRC code in the adder to produce a sum, and the sum is processed by a logical sum circuit to produce a logical sum output as a CRC flag. The CRC code generation and code error detection circuit generates CRC codes to be included in CRC code words at high speed and detects errors in received CRC code words at high speed.

CRC code generation circuit, code error detection circuit and CRC

A Cyclic Redundancy Check (CRC) code word except a fixed pattern is provided to a code data input terminal of a division circuit in synchronization with a clock signal and divided at the division circuit, then, a remainder data of the division result is outputted from output terminals. The remainder data outputted from the output terminals is compared with a CRC inherent value at a comparison circuit, and a comparison result signal indicating whether the CRC code word includes errors is outputted. A temporary memory means takes in the comparison result signal in response to rise of a clock signal inputted into a clock signal input terminal, temporarily stores it, then output its storage contents as an error detecting signal via an output node.

Code error detecting circuit

When encoding data bits in a CRC code word and '0' information is received for every bit by a dividing circuit, the CRC code word is divided by a generation polynomial and remainder data resulting from the division is output from parallel data output terminals of the dividing circuit. The remainder data is added to a CRC intrinsic value in the adder to produce a sum. The sum is a CRC code in a CRC code word for transmission. When a code error is detected, data having a plurality of bits in a CRC code word and a CRC code are received by the dividing circuit, where they are divided by the generation polynomial and remainder data is output from the respective parallel data terminals. The remainder data is added to the CRC intrinsic value in the adder to produce a sum, and the sum is processed into a logical sum in a logical sum circuit. The logical sum is output as a CRC flag. The present invention provides a CRC code generation circuit for generating a CRC code in a CRC code word at high speed as well as a code error detection circuit for detecting a code error in a CRC code word at high speed.

CRC code generation circuit, code error detection circuit, and CRC

When encoding, data bits in a CRC code word are received for every bit by a dividing circuit where the CRC code word is divided by a generation polynomial and a remainder is output from parallel data output terminals. The remainder is added to a CRC intrinsic value and '0' information in the adder. The addition result is a CRC code in a CRC code word for transmission. When a code error is detected, data bits in a CRC code word and a CRC code are received for every bit by the dividing circuit, where they are divided by the generation polynomial and a remainder is output from the respective parallel data terminals. The remainder data is added to the CRC intrinsic value in the adder, and the result is further processed by a logical sum circuit. The logical sum is output as a CRC flag. The present invention provides a CRC code generation circuit for generating a CRC code in a CRC code word at high speed as well as a code error detection circuit for detecting a code error in a CRC code word at high speed.

CRC code generation circuit for generating a CRC code and a code error

An error correction circuit is capable of performing correction errors in data at a high speed. A syndrome generator (2) calculates syndromes of RS codes based on partial data streams which are given from a data buffer (1). A received CRC generator (13) performs CRC coding on the partial data streams which are given from a data buffer (1) to thereby obtain received CRCs. An error pattern CRC generator (14) calculates error pattern CRCs of the respective partial data stream based on error patterns which are generated by an error pattern generation circuit (33). Under the control of a control circuit (40), the operations performed by the syndrome generator (2), the received CRC generator (13) and the error pattern CRC generator (14) are carried out at the same time. An improvement in the speed of error correction of the partial data streams performed by the error correction means directly leads to an improvement in the speed of the whole error correction.

Growing community of inventors

Tokyo, Japan

Kazuo Murakami