1. Field of the Invention
The present invention relates to a semiconductor chip, and more particularly, to an add-in chip that is used by being mounted on a board.
2. Description of Related Art
Conventionally, there has been known a technique of forming a semiconductor device, in which a chip having a built-in circuit performing specific processing and a substrate having the chip mounted thereon are covered with a package made of resin. Input pins and output pins extend from side surfaces of the package, and the input pins and the output pins are respectively connected to input terminals and output terminals of the built-in circuit of the chip. Through those pins, data can be input to and output from the built-in circuit. In general, there are provided a plurality of input pins, output pins, input terminals, and output terminals, and corresponding pins and terminals are connected to each other.
In recent years, as functions of a semiconductor device have become highly sophisticated, a development process therefor tends to be subdivided. Under such circumstances, in a case of developing a semiconductor device, for example, it is likely that a chip and a board having the chip mounted thereon are developed separately. In this case, the development of the chip is carried out assuming that the chip is mounted on the board. Such a chip is also called an add-in chip.
The semiconductor device 1 shown in
As shown in
Incidentally, when the board and the chip are developed separately, an order of data to be input to the board is not necessarily the same as an order requested by the built-in circuit.
The semiconductor device 2 includes a board 25 and a chip 30. A plurality of board terminals of the board 25 are arranged in an order reverse to that of the board terminals of the board 20 of the semiconductor device 1. In order to input the pieces of data Sa to Sn in the order corresponding to the order of the input terminals 41a to 41n of the built-in circuit 40, as shown in
Further, when the chip is mounted on the board, due to the physical structure of each of the board and the chip, it is necessary for the chip to be flipped over and mounted on the board in some cases.
The board 20 and the chip 30 forming the semiconductor device 3 shown in
Japanese Unexamined Patent Application Publication No. 04-340253 discloses a technology for switching a connection between terminals (see
The input terminals of the chip, the switching circuits, and the built-in circuit input terminals are arranged in the same numerical order. The built-in circuit terminals are connected to a side of the first terminals of the switching circuit in the same order as the numerical order, and are connected to a side of the second terminals of the switching circuit in the order reverse to the numerical order.
In other words, in a state where each input terminal of the chip is connected to the first terminal of the corresponding switching circuit, the built-in circuit input terminals are connected to the input terminals of the chip in the same order as the numerical order. On the other hand, in a state where each input terminal of the chip is connected to the second terminal of the corresponding switching circuit, the built-in circuit input terminals are connected to the input terminals of the chip in the order reverse to the numerical order.
Such a switching circuit can be applied to the semiconductor device 2 shown in
Further, the above-mentioned configuration is also applied to the semiconductor devices 3 and 4 shown in
Incidentally, when the technology disclosed in Japanese Unexamined Patent Application Publication No. 04-340253 is applied to the semiconductor device 2 shown in
A plurality of pieces of data to be transmitted with a predetermined synchronized relation are processed by the built-in circuit of the chip, assuming that the synchronized relation among the pieces of data is maintained. Accordingly, when the synchronized relation among the plurality of pieces of data deteriorates due to the switching circuit, the built-in circuit of the chip does not operate normally. Further, in recent years, there has been a demand for a higher data transmission speed, a high-speed data transmission technology such as PCI Express (PCI: Peripheral Component Interconnect) has been put to practical use. To meet the demand for the high-speed data transmission, functions of a semiconductor device are becoming highly sophisticated, and there is also provided a functional block operating with a high operating frequency in the built-in circuit of the chip.
Therefore, there arises a problem in that, when the above-mentioned switching circuit is provided in a chip, it is difficult to perform the switching with a frequency corresponding to the high operating frequency of the built-in circuit. In some cases, the switching is not satisfactorily performed, and there is a fear that the semiconductor device may cause a malfunction.
In one embodiment of the present invention, there is provided a semiconductor chip. The semiconductor chip includes: a first processing unit; a second processing unit operating with a frequency lower than an operating frequency of the first processing unit; a transfer unit provided between the first processing unit and the second processing unit and transferring a plurality of pieces of data between the first processing unit and the second processing unit; and a control signal terminal inputting a control signal to the transfer unit. The transfer unit includes: a plurality of transfer unit input terminals respectively inputting the plurality of pieces of data from a transmission-side processing unit which is a transmission side of one of the first processing unit and the second processing unit; a plurality of transfer unit output terminals respectively corresponding to the plurality of transfer unit input terminals, respectively, and outputting the plurality of pieces of data input from the corresponding transfer unit input terminals to a reception-side processing unit which is a reception side of one of the first processing unit and the second processing unit; and a switching unit switching a correspondence relation between the plurality of transfer unit input terminals and the plurality of transfer unit output terminals in response to the control signal from the control signal terminal.
In another embodiment of the present invention, there is provided a semiconductor device. The semiconductor chip includes: a transfer unit; and a control signal terminal inputting a control signal to the transfer unit. The transfer unit includes: a plurality of transfer unit input terminals respectively inputting a plurality of pieces of data; a plurality of transfer unit output terminals respectively corresponding to the plurality of transfer unit input terminals, respectively, and outputting the plurality of pieces of data input from the corresponding transfer unit input terminals; a switching unit switching a correspondence relation between the plurality of transfer unit input terminals and the plurality of transfer unit output terminals in response to the control signal from the control signal terminal; and a timing correction unit. The timing correction unit corrects a transfer time according to the switching by the switching unit so that the transfer time for transferring data through transfer paths between the plurality of transfer unit input terminals and the plurality of transfer unit output terminals corresponding to the plurality of transfer unit input terminals is set to be constant with respect to the plurality of pieces of data.
Note that the semiconductor chip replaced by a method, a system, or a program can be effective as an embodiment of the present invention.
With the technology of the present invention, in a case of switching a connection between terminals of a semiconductor device, it is possible to prevent the semiconductor device from causing a malfunction due to the switching.
The above and other objects, advantages and features of the present invention will be more apparent from the following description of certain preferred embodiments taken in conjunction with the accompanying drawings, in which:
The invention will now be described herein with reference to illustrative embodiments. Those skilled in the art will recognize that many alternative embodiments can be accomplished using the teachings of the present invention and that the invention is not limited to the embodiments illustrated for explanatory purposes.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the semiconductor device compliant with PCI Express, circuits receiving data from an outside of the circuits and circuits transmitting data to the outside of the circuits may be partially independent from each other and partially shared with each other. For example, in general, circuits performing physical layer processing are independent from each other for transmission and reception of data, but circuits performing processing of a link layer and upper layers are shared with each other for transmission and reception of data. For ease of explanation,
Note that, according to the PCI Express specification, data is converted into a serial low-voltage differential signal to be transmitted. Accordingly, data of each lane is transmitted using a pair of lines. For ease of explanation, the lines transmitting data of a single lane are each represented by a single line.
Data of each of Lanes 1 to 4 is serial data, and the SERDES 132 converts the data into 10-bit parallel data. A bit width of input data of a single lane is 2.5 GB, so the SERDES 132 converts the input data of each single lane into 10 pieces of data with a bit width of 250 MB. The SERDES 132 converts data of each lane in this manner, and outputs the converted data to the PCS processing unit 136 through lines 134A to 134D.
The board 112B also has four board terminals 114A to 114D for receiving pieces of data of four lanes, that is, Lanes A to D, and for outputting the received data to the chip 120. The board terminals are arranged so that the data is received in the order of Lane D, Lane C, Lane B, and Lane A from the top. In this case, in the transfer unit 150, the selection of data by the MUXs is switched in response to the control signal from the control signal terminal 160 so that the data is input to the link unit 180 in the order of Lane A, Lane B, Lane C, and Lane D. Accordingly, lines connecting each of the board terminals 114D to 114A to the chip 120 do not intersect with each other.
In other words, the data is input from the link unit 380 in a predetermined order of lanes, but the order of lanes of data output from the physical layer processing unit 330 is controlled by the control signal input from the control signal terminal 360. As a result, any combinations of Lanes 1 to 4, for example, combinations of “Lane A, Lane B, Lane C, and Lane D” and “Lane D, Lane C, Lane B, and Lane A” can be adopted.
Note that, in the chip 420, the transfer unit 450 is provided between the outside and the internal processing circuit 480. Alternatively, when the internal processing circuit 480 can be divided into two processing units having different operating frequencies, it is preferable to provide the transfer unit 450 between the two processing units.
A lower portion of
Incidentally, for example, in a case where the destination device has to be connected to the board terminal 220B or to the board terminal 220C because of limitations of a connector structure, a layout, or the like, even when the destination device is connected to the board terminal 220B or to the board terminal 220C, the data communication therebetween cannot be established due to limitations of the specification of the link unit 270 of the chip 230.
An upper portion of
A lower portion of
In this manner, by providing the transfer unit 150, four connection modes, which are used in the case of a single lane connection, are additionally provided as shown in
As in the case of a single lane connection, because of the limitations of the connector structure of the destination device, the layout, and the like, a combination of the board terminals 220B and 220C has to be used for connection in some cases. Also in the case of using the board terminals 220C and 220D, the data of Lane A and the data of Lane B may be input to the board terminals 220C and 220D, respectively. In those cases, the data communication cannot be established simply by connecting the board terminals to the destination device.
In the C/B connection, the board terminals 220B and 220C are each connected to the destination device. By the configuration parameter, data input to the board terminal 220B and data input to the board terminal 220C are set to be used as the data of Lane B and the data of Lane A, respectively. In this case, by the transfer unit 150, the data input to the input terminal 244B is output to the input terminal 260A of the link unit 270, and the data input to the input terminal 244C is output to the input terminal 260B of the link unit 270, whereby the data of Lane B and the data of Lane A are input to the two input terminals 260A and 260B of the link unit 270, respectively. This connection mode corresponds to the B/A connection supported by the link unit 270. Accordingly, the data communication between the destination device and the semiconductor device can be established.
In the above description, there is illustrated the example where the technology of the present invention is applied to the semiconductor device supporting four lanes. The number of lanes is not limited to four, and the present invention can be applied to any semiconductor device supporting an arbitrary number of lanes.
It is apparent that the present invention is not limited to the above embodiments, but may be modified and changed without departing from the scope and spirit of the invention.
Number | Date | Country | Kind |
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2007-137931 | May 2007 | JP | national |