JP2001022476A - Computer system and system substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a personal computer which can improve a degree of design freedom in a substrate design of a mounting part such as main memory where data processing is performed at high speed. SOLUTION: This device is a personal computer 1 provided with a mother board 4 having a memory socket 14 to which a memory substrate 16 mounting a memory chip 15 is fitted, a memory controller 7 for controlling an access to a memory chip 14 on the memory substrate 16 fitted to the memory socket 14 and plural wiring patterns 17 which are length adjusted and wired so that transmission distances of plural signals transmitted between the memory chip 15 on the memory substrate 16 fitted to the memory socket 14 and a chip of the memory controller 7 become identical transmission distances respectively. Thus, on the side of memory substrate 16, a wiring pattern 18 can freely be drawn without needing to adjust a wiring length of a signal line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a computer system to which a module on which an LSI chip such as a memory chip is mounted can be mounted, and a system board included in the system.

[0002]

2. Description of the Related Art With the recent innovation of information processing technology, various types of personal computers (personal computers) such as a desktop type, a notebook type, and a mobile type have been developed and marketed for general users. As is well known, a personal computer has a main memory, an RO, in addition to a CPU.
M and a number of devices such as a memory controller. An address signal line, a data signal line, a control signal line, and the like are provided between the CPU and these devices.
They are connected by a so-called bus, and the CPU and each device can exchange information with each other by exchanging signals via the bus.

The CPU is for executing various applications under the control of an OS (Operating System). The main memory is a readable / writable storage device, and is used as an area for loading the OS and applications. Alternatively, the CPU is used as a work area for executing a task. The memory controller controls the access operation to the memory chip by transmitting a signal having a combination of Low / High level to each signal line of the memory bus at a predetermined timing.

The main memory described above has a capacity larger than that of the standard memory because the storage capacity has a large effect on the execution speed of the system and the storage capacity makes large-scale applications or graphics available. In many cases, storage capacity is required. Therefore, recent personal computers generally have a structure that allows additional memory. A memory module such as a so-called DIMM is a typical example of a mountable memory, and is configured by arranging a plurality of memory chips on a memory board.

For this reason, as shown in FIG. 5, a memory socket 54 is prepared as a slot for mounting a card edge terminal of a memory board 53 of a memory module 52 on a main board 51 in a personal computer. The memory module 52 can be inserted and removed as needed.

Incidentally, the memory module 52 which can be inserted into and removed from the main board 51 comprises a memory board 53.
A plurality of wiring patterns 56 connecting the card edge terminals of the above and the electrodes of the memory chip 55 mounted on the memory substrate 53 are formed so as to have the same wiring length, respectively.
On the other hand, the main board 51 is formed such that a plurality of wiring patterns 58 connecting the electrodes of the chip constituting the memory controller 57 and the leads of the memory socket 54 have the same wiring length.

That is, the plurality of signal lines connecting the memory controller 57 on the main board 51 and the memory chip 55 on the memory module 52 are designed to have the same wiring length. Aligning the wiring lengths of the individual signal lines is to prevent a time lag (skew) during signal transmission due to the difference in signal line length, and the main memory mounting portion where high-speed data processing is performed is used. This is an essential requirement in pattern design.

[0008]

However, when the lengths of a plurality of signal lines connecting between the memory controller 57 on the main board 51 and the memory chip 55 on the memory module 52 are made uniform, the following is required. There were challenges.

In other words, in order to make the wiring lengths of the wiring patterns 56 and 58 uniform in each of the main board 51 and the memory board 53, it is necessary to make the wiring pattern 56 which is the longest in view of the layout of various mounted components.
a, and the wiring pattern 5
6b and 58b are wired. In this case, the area 56 for meandering the wiring patterns 56b and 58b is used.
c and 58c are required on each substrate.

Therefore, restrictions on designing the main board 51 and the memory board 53 are increased, and furthermore,
If the mounting components and the wiring pattern cannot be arranged even by making full use of the layout, there is a problem that the substrate must be changed to a size larger than a desired size.

The present invention has been made in order to solve such a problem. For example, in a board design of a mounting portion of a main memory or the like where data processing is performed at a high speed, the degree of design freedom is improved. It is an object of the present invention to provide a computer system and a system board that can perform the same.

[0012]

In order to achieve the above object, a computer system according to the present invention has a first substrate on which an integrated circuit chip is mounted, as described in claim 1. A socket, a control circuit chip for controlling access to the integrated circuit chip on the first substrate mounted on the socket, and the integrated circuit chip on the first substrate mounted on the socket; The transmission distance of a plurality of signals transmitted between the control circuit chip is
It is characterized by having a second substrate provided with a plurality of wiring patterns, the lengths of which are adjusted so that the transmission distances are substantially the same.

Further, the computer system of the present invention comprises:
As described in claim 2, a socket on which a memory board on which a memory chip is mounted is mounted, and a control circuit chip for controlling access to the memory chip on the memory board mounted on the socket. The transmission distance of a plurality of signals transmitted between the memory chip and the control circuit chip on the memory board mounted on the socket is adjusted and wired so that the transmission distance of each signal is substantially the same. And a system board having a plurality of wiring patterns.

Further, according to a third aspect of the present invention, there is provided a system board, wherein a socket on which a memory board on which a memory chip is mounted is mounted, and the socket on the memory board mounted on the socket is provided. The transmission distances of a plurality of signals transmitted between the control circuit chip for controlling access to the memory chip and the memory chip on the memory board mounted on the socket and the control circuit chip are substantially the same. And a plurality of wiring patterns whose lengths are adjusted to be equal to the transmission distance and which are wired.

According to the first to third aspects of the present invention, a plurality of data transmitted between, for example, a memory chip mounted on a socket on a memory substrate and a control circuit chip for controlling access to the memory chip are provided. A wiring pattern whose length has been adjusted so that the signal transmission distances are substantially the same is provided on, for example, a main board.
That is, in these inventions, adjustment of the wiring length for suppressing the occurrence of a time difference (skew) at the time of transmitting a signal (especially a signal transmitted and received at a high speed) due to a difference in the length of the signal line is performed only on the system board side. This is essentially done.

Therefore, according to these inventions, it is not necessary to adjust the wiring length of the signal line on the memory substrate side.
Since wiring patterns can be freely drawn, restrictions in designing a memory substrate, that is, restrictions in layout when arranging mounted components and wiring patterns on the memory substrate are reduced, and the degree of freedom in design is reduced. Can be improved.

Further, the computer system of the present invention comprises:
5. A board body mounted on a socket mounted on a system board, and a memory mounted on the board body and accessed by a control circuit chip mounted on the system board, as described in claim 4. The length of the chip is adjusted such that the transmission distances of a plurality of signals transmitted between the memory chip and the control circuit chip on the board main body mounted on the socket are substantially equal to each other. A memory substrate having a plurality of wired wiring patterns is provided.

According to the present invention, the adjustment of the wiring length for suppressing the occurrence of the time difference at the time of signal transmission due to the difference in the length of the signal line is substantially performed only on the memory substrate side. Therefore, according to the present invention, it is not necessary to adjust the wiring length of the signal line on the main board side, and the wiring pattern can be freely drawn, so that the restriction on designing the main board is reduced, The degree of freedom of target can be improved.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view schematically showing a personal computer according to an embodiment of the present invention.

As shown in FIG. 1, the personal computer 1 is a notebook type useful when being carried, and includes a personal computer main body 2 having a storage device such as a hard disk and an input device such as a keyboard, and a keyboard and the like. Liquid crystal display panel 3 for visually displaying information input through a user to a user
It is composed of As shown in FIG. 2, a motherboard 4 as a system board on which various electronic components including a CPU, a ROM, and the like are mounted is incorporated in the personal computer body 2.

FIG. 3 is a block diagram showing a connection relationship of main hardware mounted on the motherboard 4. As shown in FIG. As shown in the figure, the CPU 5 sends a Low signal to each device.
It is connected to a so-called north bridge (North bridge) 7a of a chip set via a host bus 6a composed of an address bus, a data bus, and a control bus for exchanging signals composed of a combination of / High level. In addition, a PCI (Pe
ripheral Component Interconnect) through IS
An A (Industry Standard Architecture) bus controller 8 is connected.

The CPU 5 executes various applications under the control of the OS, and makes a memory access request to the memory controller 7 realized by the north bridge 7a as needed.

The ISA bus controller 8 controls data exchange between the PCI bus 6 and the ISA bus 9. The ISA bus 9 has a hardware control program (BIOS: BasicInput / Out) written at the time of manufacture.
ROM (Read O) in which the put system is coded and stored
nly Memory) 10 and other peripheral devices such as a hard disk drive, a floppy (registered trademark) disk drive, and a keyboard / mouse.

The memory controller 7 includes a memory address bus (MA) composed of a plurality of signal lines for specifying a memory address, and a plurality of row address read signal lines for controlling timing of reading a row address of each memory chip. RAS (Row Address Strobe), and a plurality of column address read signal lines CAS (Column Add) for controlling the read timing of the column address of each memory chip.
(ress Strobe) and a memory socket 11 including a WE, which is a signal line for energizing a data write operation, to a memory socket 14 on which an on-board memory 12 and a memory module 13 are mounted.

That is, the memory controller 7 controls the CP
This is a device that can determine the location of the DRAM chip in the main memory where the data requested to be accessed via U5 is located, and perform the access. Further, the memory controller 7, the on-board memory 12, and the memory socket 14 are bidirectionally connected through a data bus in the memory bus 11, so that the CPU 11 can read and write information.

DRAM (Dynamic Random Access Memor)
y) and the like, an on-board memory 12 in which a memory chip is surface-mounted on a motherboard 4, and a DIMM (Dual Inline Memory) in which a plurality of memory chips are mounted on a memory board.
The memory module 13 is a readable / writable storage device, and is used as an area for loading an OS or an application, or as a work area for a CPU to execute a task.

Next, the connection relationship between the memory socket 14 surface-mounted on the motherboard 4 and the memory controller 7 will be described in detail.

The memory module 13 is used to extend the storage capacity of the main memory of the personal computer 1 in addition to the storage capacity of the on-board memory 12, and as shown in FIG. When mounted in the memory socket 14, the memory socket 14 and the memory module 13 are electrically connected to each other through an edge terminal of an edge of the memory board 16 on which the memory chip 15 is surface-mounted.

On the other hand, the motherboard 4 on which the memory controller 7 realized by the north bridge 7a is mounted is transmitted between the memory controller 15 and the memory chip 15 on the memory module 13 mounted on the memory socket 14. A plurality of wires whose lengths have been adjusted so that the transmission distances of the plurality of signals are the same as each other, that is, a time difference (skew) does not occur between signals transmitted at high speed between the memory buses 11. A pattern 17 is provided.

That is, among the wiring patterns 18 connecting the edge terminals of the memory substrate 16 of the memory module 13 and the electrodes of the memory chip 15, for example, the wiring pattern 18a and the wiring pattern 18b have different wiring lengths. However, among the wiring patterns 17 for connecting the leads of the memory socket 14 and the electrodes of the memory controller 7, for example, the wiring length of the wiring patterns 17a and 17b depends on the wiring lengths of the wiring patterns 18a and 18b. Due to the adjustment, the signal transmission distance between the memory controller 7 and the memory chip 15 is substantially the same. The thickness of each of the wiring patterns 17 and 18 is, of course, substantially the same.

Therefore, the wiring length of the wiring pattern will be further described.
If the wiring length of the wiring pattern 18 is Length (sys) and the wiring length of the wiring pattern 18 of the memory substrate 16 is Length (exp), Length (sys) of the pattern 17a + Length (ex) of the pattern 18a
p) = Length (sys) of pattern 17b + of pattern 18b
The wiring length of each wiring pattern 17 is adjusted so as to be Length (exp).

As described above, the personal computer 1 of this embodiment is
A plurality of signals transmitted between a memory chip 15 on a memory board 16 mounted on a memory socket 14 and a north bridge 7a (LSI chip) realizing a memory controller 7 for controlling access to the memory chip 15 A plurality of wiring patterns 17 whose lengths are adjusted so that the transmission distances are the same as each other are provided on the motherboard 4. That is, the personal computer 1 substantially adjusts the wiring length only on the motherboard 4 side to suppress the occurrence of a time difference when transmitting a signal (especially a signal transmitted and received at a high speed) due to a difference in signal line length. It is.

Therefore, according to the personal computer 1 of this embodiment, it is not necessary to adjust the wiring length of the signal lines on the memory board 16 side, and the wiring pattern 18 can be freely drawn. Restrictions on designing, that is, restrictions on layout when arranging mounted components and wiring patterns on the memory board 16 are reduced,
The degree of freedom in design can be improved.

In the present embodiment, the pattern design of the mounting portion of the main memory as the main storage device has been described, but the present invention is not limited to such a configuration. That is, in addition to the pattern design of the board of the mounting part such as the video memory of the display controller for controlling the display information on the display panel 3 or the buffer memory of the printer,
The present invention can also be applied to a pattern design of a substrate on a mounting portion of various LSI chips for transmitting a signal at a high speed.

In this embodiment, the case where the wiring length of the wiring pattern 17 on the motherboard 4 is adjusted has been described. However, the board design is changed so that the wiring length of the wiring pattern 18 on the memory substrate 16 is adjusted. You may.

Further, in the present embodiment, the case where the wiring lengths of the wiring patterns between the memory controller 7 and the memory chip 15 are equalized has been described. However, when a time difference is required between transmitted signals in terms of design, The length of the wiring pattern 17 may be adjusted so that the length of the wiring pattern between the memory controller 7 and the memory chip 15 is intentionally different.

In this embodiment, the case where the present invention is applied to a portable notebook personal computer has been described. However, it is assumed that the main memory as the main storage device is entirely constituted by the mountable memory module 13. Of course, the present invention can be applied to many desktop personal computers.

[0039]

As described above, according to the first to third aspects of the present invention, there is provided a memory chip mounted on a socket, for example, a memory chip on a memory board, and a control circuit chip for controlling access to the memory chip. For example, a plurality of wiring patterns whose lengths are adjusted so that transmission distances of a plurality of signals transmitted between them are substantially equal to each other are provided on, for example, a main board. In other words, these inventions enable the adjustment of the wiring length to suppress the occurrence of a time difference at the time of transmitting a signal (especially a signal transmitted and received at a high speed) due to the difference in the length of the signal line, substantially only on the system board side. Is what you do.

Therefore, according to these inventions, it is not necessary to adjust the wiring length of the signal line on the memory substrate side.
Since wiring patterns can be freely drawn, restrictions in designing a memory substrate, that is, restrictions in layout when arranging mounted components and wiring patterns on the memory substrate are reduced, and the degree of freedom in design is reduced. Can be improved. Further, in the invention described in claim 4, the adjustment of the wiring length for suppressing the occurrence of the time difference at the time of signal transmission due to the difference in the length of the signal line is substantially performed only on the memory substrate side. Therefore, according to the present invention, it is not necessary to adjust the wiring length of the signal line on the main board side, and the wiring pattern can be freely drawn, so that the restriction on designing the main board is reduced, The degree of freedom of target can be improved.

[Brief description of the drawings]

FIG. 1 is an exemplary perspective view schematically showing a personal computer according to an embodiment of the present invention;

FIG. 2 is an exemplary sectional view showing the internal structure of the personal computer in FIG. 1;

FIG. 3 is an exemplary block diagram showing a connection relationship of main hardware mounted on a motherboard inside the personal computer in FIG. 1;

FIG. 4 is an exemplary diagram schematically showing a connection relationship between a memory controller on a motherboard of the personal computer in FIG. 1 and a memory module;

FIG. 5 is a diagram schematically showing a connection relationship between a memory controller on a motherboard of a conventional personal computer and a memory module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Personal computer 4 ... Motherboard 5 ... CPU 6 ... PCI bus 7 ... Memory controller 7a ... North bridge 11 ... Memory bus 12 ... Onboard memory 13 ... Memory module 14 ... Memory socket 15 … Memory chip 16… memory board 17, 18… wiring pattern

Claims (4)

[Claims] A socket on which a first substrate on which an integrated circuit chip is mounted is mounted; and a control circuit chip for controlling access to the integrated circuit chip on the first substrate mounted on the socket. Length adjustment such that transmission distances of a plurality of signals transmitted between the integrated circuit chip and the control circuit chip on the first substrate mounted on the socket are substantially equal to each other. A computer system comprising: a second substrate having a plurality of wiring patterns arranged and wired. 2. A socket on which a memory board on which a memory chip is mounted is mounted, a control circuit chip for controlling access to the memory chip on the memory board mounted on the socket, and a control circuit chip mounted on the socket. A plurality of wiring patterns, the transmission distances of a plurality of signals transmitted between the memory chip and the control circuit chip on the memory substrate, the lengths of which are adjusted to be substantially the same transmission distance, and a plurality of wiring patterns. A computer system comprising a system board provided with: 3. A socket on which a memory board on which a memory chip is mounted is mounted, a control circuit chip for controlling access to the memory chip on the memory board mounted on the socket, and a control circuit chip mounted on the socket. A plurality of wiring patterns, the transmission distances of a plurality of signals transmitted between the memory chip and the control circuit chip on the memory substrate, the lengths of which are adjusted to be substantially the same transmission distance, and a plurality of wiring patterns. A system board comprising: 4. A board body mounted on a socket mounted on a system board; a memory chip mounted on the board body and accessed by a control circuit chip mounted on the system board; A plurality of wires whose lengths are adjusted and wired so that transmission distances of a plurality of signals transmitted between the memory chip and the control circuit chip on the mounted substrate main body are substantially equal to each other. A computer system comprising a memory board having a pattern.