JP2022165844A - Library development support program, library development support method and information processing device - Google Patents

Abstract

To reduce cost to be needed for development of a circuit library.SOLUTION: An information processing device 101 acquires design data D about a measurement object circuit TC. The information processing device 101 specifies a place that operates in a measurement object circuit TC on the basis of an operation simulation using the acquired design data D. The information processing device 101 replaces a cell of another place different from the specified place that operates in the acquired design data D with a cell for replacement specified in accordance with a measurement item of the an operation characteristic with reference to a storage part 110. The storage part 110 stores a plurality of cells for replacement prepared in advance. The information processing device 101 creates a net list NL for operation characteristic measurement about the measurement object circuit TC on the basis of replaced design data D.SELECTED DRAWING: Figure 1

Description

The present invention relates to a library development support program, a library development support method, and an information processing apparatus.

Conventionally, in LSI (Large Scale Integration) design, parts such as standard cells such as flip-flops that hold basic gates and data, custom macros designed exclusively for computing units, and memory macros that are used to hold large amounts of data. used. These parts are provided, for example, in the form of library data used by LSI design tools. There are various types of libraries, such as circuit libraries with timing constraint information, power information, and the like.

As a prior art, a low-precision simulation is performed using a test pattern created according to the function to be simulated, signals with waveforms that change more than a certain amount are extracted, and the extracted signals are used as netlists. and run high-precision simulations. Also, the description controlling the circuit operation described in the circuit information is extracted as control description information, the signal propagating from the testbench information to the operation control description is extracted as control pattern information, and the control description information and the control pattern information are extracted. There is a technique for identifying control descriptions that do not operate from the data and deleting the control descriptions that do not operate.

JP-A-2002-108965 JP 2007-133451 A

However, in the conventional technology, there is a problem that development of a circuit library used for LSI design or the like takes time and costs such as computer resources.

In one aspect, the present invention aims to reduce the cost of developing circuit libraries.

In one embodiment, design data relating to a circuit to be measured for operating characteristics is obtained, based on a result of an operation simulation using the obtained design data, a portion of the circuit to be measured that operates is specified, and Among the design data, a cell at a location different from the identified operating location is identified according to the measurement item of the operating characteristic by referring to a storage unit storing a plurality of replacement cells prepared in advance. A library development support program is provided that replaces the circuit with a replacement cell that is to be replaced, and creates a netlist for measuring operating characteristics of the circuit to be measured based on the design data after replacement.

According to one aspect of the present invention, it is possible to reduce the cost of developing a circuit library.

FIG. 1 is an explanatory diagram of an example of a library development support method according to an embodiment. FIG. 2 is an explanatory diagram showing a system configuration example of the information processing system 200. As shown in FIG. FIG. 3 is a block diagram showing a hardware configuration example of the library development support device 201. As shown in FIG. FIG. 4 is an explanatory diagram showing an example of the contents stored in the cell replacement DB 220. As shown in FIG. FIG. 5 is a block diagram showing a functional configuration example of the library development support device 201. As shown in FIG. FIG. 6 is an explanatory diagram of an example of a circuit to be measured. FIG. 7 is an explanatory diagram showing a specific example of simulation results. FIG. 8 is an explanatory diagram showing a specific example of the active list. FIG. 9 is an explanatory diagram showing a specific example of connection information. FIG. 10 is an explanatory diagram showing a specific example of operation blocks. FIG. 11 is an explanatory diagram (Part 1) of a first replacement example of a non-operating block in a circuit to be measured. FIG. 12 is an explanatory diagram (part 2) of a first replacement example of a non-operating block in the circuit to be measured. FIG. 13 is an explanatory diagram (part 1) showing a specific example of correspondence information. FIG. 14 is an explanatory diagram (part 2) showing a specific example of correspondence information. FIG. 15 is an explanatory diagram of a second replacement example of non-operating blocks in the circuit to be measured. 16A is an explanatory diagram (part 1) showing an operation example of the library development support device 201. FIG. FIG. 16B is an explanatory diagram (Part 2) showing an operation example of the library development support device 201 . 16C is an explanatory diagram (part 3) showing an operation example of the library development support device 201. FIG. FIG. 17 is an explanatory diagram showing an example of data processing by the library development support device 201. As shown in FIG. FIG. 18 is a flow chart showing a data processing procedure of the library development support device 201. As shown in FIG. FIG. 19 is a flowchart illustrating an example of a specific processing procedure for replacement processing. FIG. 20 is an explanatory diagram showing an example of a memory circuit. FIG. 21 is an explanatory diagram showing the flow of read data in the memory circuit. FIG. 22 is an explanatory diagram of an example of a memory circuit after replacement. FIG. 23 is an explanatory diagram of an example of a decoding circuit. FIG. 24 is an explanatory diagram of an example of a decoding circuit after replacement.

Exemplary embodiments of a library development support program, a library development support method, and an information processing apparatus according to the present invention will be described below in detail with reference to the drawings.

(Embodiment)
FIG. 1 is an explanatory diagram of an example of a library development support method according to an embodiment. In FIG. 1, an information processing apparatus 101 is a computer that supports measurement of operating characteristics of a circuit to be measured. The operating characteristics of the circuit under test are, for example, timing constraints, power, etc. of the circuit under test.

In recent years, the development man-hours for circuit libraries have increased due to the increase in variation due to the miniaturization of manufacturing processes, the increase in verification conditions due to lower voltages to reduce power consumption, and the increase in the amount of information to improve library accuracy. there is A circuit library is a library that has timing constraint information, power information, and the like for each component. Components are, for example, standard cells such as basic gates and flip-flops (hereinafter referred to as "STD cells"), custom macros, memory macros, and the like.

In conventional circuit library development, layout data and circuit diagram data are created as design data, and LVS (Layout Versus Schematic) is executed after the design is completed. Circuit diagram data is circuit information describing circuit elements and their connection relationships (for example, information indicating connection relationships between elements A and B).

Layout data is physical information describing an actual manufacturing pattern (for example, information indicating the layout of circuit elements arranged on a substrate). LVS is a process for checking that circuit diagram data and layout data match. In LVS, confirmation of matching between circuit diagram data and layout data and extraction of layout shape information are performed.

Next, in conventional circuit library development, LPE (Layout Parasitic Extraction) is executed from layout shape information and environmental conditions. Environmental conditions include temperature, wiring variation conditions, and the like. In LPE, layout wiring resistance and parasitic capacitance are extracted, and an LPE netlist is created. The LPE netlist is data including circuit connection information, shape data of circuit elements, and parasitic element information.

For example, the LPE netlist is a normal netlist showing connection relationships between elements, and includes parasitic element information for calculating delay in simulation, such as resistance and capacitance attached to wiring. In general, the resistance value depends on the temperature, and the capacitance value depends on the wiring variation condition. For this reason, the number of LPE netlists corresponding to, for example, "temperature×wiring variation condition" is created.

A circuit library is generated by, for example, measuring data necessary for the library using a circuit library measurement tool (hereinafter referred to as "lib measurement tool"). For example, by inputting an LPE netlist, measurement patterns required for various measurements (what kind of signals to input), and setting files describing tool settings and measurement conditions into the lib measurement tool and executing it, the circuit library will be output. be done. When a circuit library is prepared for each verification condition, lib measurement tools are executed for the number of verification conditions.

The lib measurement tools are roughly divided into timing constraints and power measurements. Timing constraints are, for example, input signal setup time, hold time, input capacitance, and delay value from input to output. Power is, for example, leak power that is always consumed regardless of whether or not there is an operation, and dynamic power that is consumed by charging/discharging wiring capacitance during operation.

Custom macros and memory macros are designed by combining, for example, multiple circuit blocks (hereinafter referred to as "blocks") that combine STD cells and dedicated circuits. For timing constraint measurements, the required block is part of the overall circuit. For example, when measuring the setup time and hold time of an input signal, it is sufficient to have a flip-flop that holds the input signal and a related control circuit. For this reason, the measurement of the timing constraint is performed, for example, after analyzing the input LPE netlist and extracting only necessary blocks.

On the other hand, in power measurement, since all transistors are required for leakage power measurement, the input LPE netlist is used as it is. For this reason, as measurement patterns, for timing constraints, prepare patterns that operate the blocks you want to measure, and for power, patterns that perform the necessary operations (maximum power operation, minimum power operation, etc.) for the entire macro. prepare.

In a large-scale macro, the number of elements included in the LPE netlist becomes millions of transistors and tens of millions of parasitic elements, and the execution time of the lib measurement tool and the resource usage of the computer become extremely large. Therefore, it is conceivable to extract the parasitic elements of the specified transistors and nets from the LPE netlist, compress the LPE netlist size, and shorten the execution time of the lib measurement tool and reduce the resource usage of the computer.

For example, based on the netlist, the pattern used for evaluation is used for high-speed, low-accuracy simulation to identify the operating locations, create a netlist that extracts the operating locations from the netlist of the entire circuit, and perform a high-accuracy simulation. There is a technique 1 (see, for example, Patent Document 1). In addition, there is a prior art 2 that reduces the circuit size by removing descriptions that do not operate on a test bench used for verification in a circuit designed in a hardware description language (see, for example, Patent Document 2).

Specifically, for example, in the prior art 1, first, low-precision, high-speed functional simulation is performed using measurement patterns and circuit diagram data. This functional simulation only needs to operate correctly and does not take into consideration minute changes in signals or timing. Conventional technology 1 creates an active list from simulation results. The active list is a list of information on nets and devices operating in the circuit.

Next, prior art 1 extracts the parasitic elements and devices of the nets included in the active list from the LPE netlist, and compresses the LPE netlist narrowed down to the nets and devices operating in the measurement pattern (hereinafter referred to as " compressed LPE netlist"). Then, according to the prior art 1, the compressed LPE netlist is input to the lib measurement tool and library measurement is performed.

However, prior art 1 can only deal with items that are measured using a part of the circuit, such as timing constraints, and cannot deal with power measurement. For example, in power measurement, the compressed LPE netlist of prior art 1 cannot be used because leakage power cannot be measured correctly if an element is deleted.

Also, in a large-scale circuit, an LPE netlist with millions of transistors and tens of millions of parasitic elements is created. In order to deal with many verification conditions, it is necessary to create a plurality of LPE netlists with different variation conditions and temperature conditions. Therefore, in prior art 1, there is a problem that a lot of computer resources are required for creating a netlist, extracting a compressed LPE netlist, and managing data.

Therefore, in the present embodiment, a library development support method for reducing costs such as computer execution time and computer resources required for circuit library development will be described. Here, a processing example of the information processing apparatus 101 will be described.

(1) The information processing device 101 acquires the design data D regarding the circuit to be measured TC. Here, the circuit to be measured TC is a circuit whose operating characteristics are to be measured. For example, the circuit to be measured TC is a circuit such as an STD cell, a custom macro, or a memory macro registered as a component in a circuit library.

The design data D includes, for example, circuit diagram data sd regarding the circuit to be measured TC and layout data ld regarding the circuit to be measured. The circuit diagram data sd is circuit information describing circuit elements and their connection relationships. The layout data ld is physical information describing actual manufacturing patterns. The circuit diagram data sd and layout data ld are information used for layout verification, for example.

(2) The information processing apparatus 101 identifies the operating portion of the circuit to be measured TC based on the result of the operation simulation using the acquired design data D. FIG. Here, the operation simulation is a simulation for confirming the operation of the circuit to be measured TC. For example, when confirming the operation of a certain function, a simulation is executed using a measurement pattern (input signal test pattern) created according to the function.

In the example of FIG. 1, it is assumed that an operating portion 120 is identified as an operating portion of the circuit to be measured TC.

(3) The information processing apparatus 101 refers to the storage unit 110 to identify, in the acquired design data D, cells at other locations different from the identified operating location according to the measurement items of the operating characteristics. Replace with the replacement cell that Storage unit 110 stores a plurality of replacement cells prepared in advance. Measurement items include, for example, timing constraints and power.

Timing constraints are, for example, setup time, hold time, input capacitance, delay value, and the like. Power is, for example, leakage power and dynamic power. The replacement process with the replacement cell is performed for each of the circuit diagram data sd and the layout data ld included in the design data D, for example.

When the operating characteristics are timing constraints, the setup time and the like can be measured correctly even if the cells in the circuit TC to be measured that do not operate are deleted. On the other hand, when the operating characteristic is power, if a cell in the circuit to be measured TC is deleted, for example, leak power cannot be measured correctly.

For this reason, the information processing apparatus 101 refers to the storage unit 110 to identify a cell for replacement according to the measurement item of the operating characteristic, and replaces the identified cell at a location different from the identified operating location. replace with the cell for At this time, the information processing apparatus 101 may, for example, replace some of the cells in other locations with replacement cells, or replace all cells in other locations with replacement cells.

Specifically, for example, when the measurement item is a timing constraint, the information processing apparatus 101 refers to the storage unit 110 to identify a cell to be deleted for deleting a cell at another location, and removes a cell at another location. with the identified deleted cell. Further, when the measurement item is power, the information processing apparatus 101 refers to the storage unit 110 to identify an input-fixed cell that fixes the input by cutting the signal propagation at another location, and determines the cell at the other location. , replaces the specified input fixed cell.

In the example of FIG. 1, a portion other than the operating portion 120 in the circuit to be measured TC is referred to as a "non-operating portion 130". In this case, for example, when the measurement item is timing constraint, the information processing apparatus 101 replaces the cell 131 of the non-operating portion 130 with the deletion cell. Further, when the measurement item is power, the information processing apparatus 101 replaces the cell 131 of the non-operating portion 130 with the input fixed cell.

(4) The information processing apparatus 101 creates a netlist NL for measuring operating characteristics of the circuit to be measured TC based on the design data D after replacement. Here, the netlist NL for measuring operating characteristics is a netlist for measuring operating characteristics such as timing constraints and power regarding the circuit to be measured TC.

Specifically, for example, the information processing apparatus 101 creates an LPE netlist by executing LPE using circuit diagram data sd after replacement and layout data ld after replacement. An LPE netlist is an example of a netlist NL for measuring operating characteristics. For example, an ordinary netlist includes parasitic element information for calculating delays in simulations, such as resistance and capacitance attached to wiring. is.

As described above, according to the information processing apparatus 101, when creating the netlist NL for measuring the operating characteristics of the circuit to be measured TC, the design data D is processed to delete circuit blocks unnecessary for measuring the operating characteristics. Also, it is possible to suppress unnecessary signal propagation for measuring operating characteristics.

As a result, it is possible to reduce the execution time and the amount of resources used to create the netlist NL for measuring operating characteristics. In addition, since the data amount of the generated netlist NL itself is reduced, the execution time and resources used in the subsequent lib measurement tool are reduced, and the cost of library development can be reduced.

(System configuration example of information processing system 200)
Next, a system configuration example of an information processing system 200 including the information processing apparatus 101 shown in FIG. 1 will be described. Here, a case where the information processing apparatus 101 shown in FIG. 1 is applied to the library development support apparatus 201 in the information processing system 200 will be described as an example. The information processing system 200 is applied, for example, to a service that supports the development of libraries used for LSI design.

FIG. 2 is an explanatory diagram showing a system configuration example of the information processing system 200. As shown in FIG. In FIG. 2, an information processing system 200 includes a library development support device 201 and a client device 202 . In information processing system 200 , library development support device 201 and client device 202 are connected via wired or wireless network 210 . The network 210 is, for example, the Internet, a LAN (Local Area Network), a WAN (Wide Area Network), or the like.

Here, the library development support device 201 is a computer that has a cell replacement DB (Database) 220 and supports the development of circuit libraries. A circuit library is a library containing timing constraint information, power information, etc., and is used for LSI design, for example. The library development support device 201 is, for example, a server.

The contents stored in the cell replacement DB 220 will be described later with reference to FIG. The storage unit 110 illustrated in FIG. 1 corresponds to the cell replacement DB 220, for example.

A client device 202 is a computer used by a user of the information processing system 200 . The user is, for example, a circuit library developer. The client device 202 is, for example, a PC (Personal Computer), a tablet PC, or the like.

Although the library development support device 201 and the client device 202 are provided separately here, the present invention is not limited to this. For example, the library development support device 201 may be implemented by the client device 202 . The information processing system 200 may also include a plurality of client devices 202 .

(Hardware Configuration Example of Library Development Support Device 201)
FIG. 3 is a block diagram showing a hardware configuration example of the library development support device 201. As shown in FIG. 3, the library development support device 201 includes a CPU (Central Processing Unit) 301, a memory 302, a disk drive 303, a disk 304, a communication I/F (Interface) 305, and a portable recording medium I/F 306. and a portable recording medium 307 . Also, each component is connected by a bus 300 .

Here, the CPU 301 controls the entire library development support device 201 . The CPU 301 may have multiple cores. The memory 302 has, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), a flash ROM, and the like. Specifically, for example, the flash ROM stores the OS program, the ROM stores the application program, and the RAM is used as a work area for the CPU 301 . A program stored in the memory 302 is loaded into the CPU 301 to cause the CPU 301 to execute coded processing.

The disk drive 303 controls data read/write with respect to the disk 304 under the control of the CPU 301 . The disk 304 stores data written under the control of the disk drive 303 . Examples of the disk 304 include a magnetic disk and an optical disk.

The communication I/F 305 is connected to the network 210 through a communication line, and is connected to an external computer (for example, the client device 202 shown in FIG. 2) via the network 210 . A communication I/F 305 serves as an interface between the network 210 and the inside of the apparatus, and controls input/output of data from an external computer. For the communication I/F 305, for example, a modem or a LAN adapter can be adopted.

A portable recording medium I/F 306 controls reading/writing of data from/to a portable recording medium 307 under the control of the CPU 301 . The portable recording medium 307 stores data written under control of the portable recording medium I/F 306 . Examples of the portable recording medium 307 include CD (Compact Disc)-ROM, DVD (Digital Versatile Disk), USB (Universal Serial Bus) memory, and the like.

Note that the library development support device 201 may have, for example, an input device, a display, etc., in addition to the components described above. Also, the client device 202 shown in FIG. 2 can be realized by a hardware configuration similar to that of the library development support device 201 . However, the client device 202 has, for example, an input device and a display in addition to the components described above.

(Storage contents of cell replacement DB 220)
Next, the storage contents of the cell replacement DB 220 that the library development support device 201 has will be described. The cell replacement DB 220 is realized by storage devices such as the memory 302 and the disk 304, for example.

FIG. 4 is an explanatory diagram showing an example of the contents stored in the cell replacement DB 220. As shown in FIG. 4, the cell replacement DB 220 stores replacement cell data (for example, replacement cell data 411 to 413, 421 to 423, 431 to 437, 441 to 447) representing replacement cells for each cell type.

The cell type indicates the type of replacement cell. Cell types include, for example, a basic cell, a deleted cell, an input fixed cell 1, an input fixed cell 2, and the like. Basic cells are, for example, buffers, AND gates, OR gates, and the like. A deleted cell indicates a replacement cell for deleting a cell. Input fixing cell 1 indicates a replacement cell for fixing the input to ground (0). The input fixing cell 2 indicates a replacement cell for fixing the input to the power supply voltage (1).

For example, replacement cell data 421 represents a replacement cell for deleting a buffer. Replacement cell data 431 represents a replacement cell for fixing the input to the buffer to the ground. Also, replacement cell data 441 represents a replacement cell for fixing the input to the buffer to the power supply voltage.

The cell replacement DB 220 may not include, for example, replacement cell data 411 to 413 representing basic cells. In addition to the replacement cells described above, the cell replacement DB 220 may store, for example, replacement cells having only wiring data necessary for connection.

(Example of functional configuration of library development support device 201)
FIG. 5 is a block diagram showing a functional configuration example of the library development support device 201. As shown in FIG. 5, the library development support device 201 includes an acquisition unit 501, a specification unit 502, a replacement unit 503, a creation unit 504, a generation unit 505, an output unit 506, and a storage unit 510. Acquisition unit 501 to output unit 506 are functions of a control unit. or by the communication I/F 305, the function is realized. The processing results of each functional unit are stored in a storage device such as the memory 302 or disk 304, for example. Also, the storage unit 510 is realized by a storage device such as the memory 302 and the disk 304, for example. Specifically, for example, the storage unit 510 stores the cell replacement DB 220 shown in FIG.

The acquisition unit 501 acquires the design data D regarding the operating characteristic measurement target circuit TC. The design data D includes, for example, circuit diagram data sd regarding the circuit to be measured TC and layout data ld regarding the circuit to be measured TC. Since the circuit diagram data sd has a smaller amount of data than the layout data ld, high-speed processing is possible. The layout data ld can also be processed at high speed by using a dedicated processing tool, for example.

Specifically, for example, the acquisition unit 501 acquires the received design data D by receiving the design data D from the client device 202 shown in FIG. Further, the obtaining unit 501 may obtain the designated design data D from a design data DB (not shown) by receiving designation of the design data D from the client device 202 . Further, the acquisition unit 501 may acquire design data D input by a user's operation using an input device (not shown). An example of the circuit to be measured TC will be described later with reference to FIG.

The specifying unit 502 specifies an operating portion of the circuit to be measured TC based on the result of the operation simulation using the acquired design data D. FIG. Specifically, for example, the specifying unit 502 performs a functional simulation using the circuit diagram data sd regarding the circuit to be measured TC and a measurement pattern prepared in advance.

The function simulation is an operation simulation for confirming the operation that implements the functions of the circuit under test TC. A measurement pattern represents an input signal and is created according to a function to be simulated. A specific example of the results of the functional simulation will be described later with reference to FIG.

Next, the identifying unit 502 creates an active list from the result of the functional simulation. The active list is a list of information on nets and devices operating in the circuit. Based on the created active list and connection information, the identifying unit 502 identifies the operating portion of the circuit to be measured TC.

The connection information is information indicating the connection relationship between the cells in the circuit under test TC and the net. The connection information can be obtained, for example, by executing LVS on the circuit diagram data sd and the layout data ld regarding the circuit to be measured TC. A specific example of the active list will be described later with reference to FIG. A specific example of the connection information will be described later with reference to FIG. An example of identifying an operating portion of the circuit to be measured TC will be described later with reference to FIG.

Note that the operation simulation may be executed in another computer different from the library development support device 201. FIG. In this case, the identification unit 502 acquires the result of the motion simulation from another computer, for example.

The replacing unit 503 refers to the storage unit 510, and replaces the cell in the acquired design data D, which is different from the specified location, with the replacement cell specified according to the measurement item of the operating characteristics. Replace. Here, storage unit 510 stores a plurality of replacement cells prepared in advance. Measurement items include, for example, timing constraints and power.

Timing constraints are, for example, setup time, hold time, input capacitance, delay value, and the like. Power is, for example, leakage power and dynamic power. The replacement process with the replacement cell is performed for each of the circuit diagram data sd and the layout data ld included in the design data D, for example.

Specifically, for example, when the measurement item is a timing constraint, the replacement unit 503 refers to the cell replacement DB 220 shown in FIG. Replace the cell at the location with the identified deleted cell. At this time, the replacing unit 503 may, for example, replace some cells in other locations with deleted cells, or may replace all cells in other locations with deleted cells.

Further, when the measurement item is power, replacement section 503 refers to cell replacement DB 220 to specify an input-fixed cell whose input is fixed by cutting signal propagation in cells at other locations. is replaced with the specified input fixed cell. At this time, the replacing unit 503 may, for example, replace some cells in other locations with input-fixed cells, or replace all cells in other locations with input-fixed cells.

The input fixed cell is a replacement cell for suppressing signal propagation at other locations. According to the fixed input cell, for example, the input to the cell at another location is fixed to the ground or the power supply voltage so as not to be in a floating state while disconnecting the connection relationship between the cell at another location and another cell. be able to.

For example, the measurement item is "power", the cell at another location is "buffer", and the input to that cell is "0". In this case, the replacement unit 503 refers to the cell replacement DB 220 to specify an input fixing cell (replacement cell data 431) for fixing the input to the buffer to ground (0). Then, the replacing unit 503 replaces the cells at other locations with the specified input fixed cells (replacement cell data 431).

Also, the measurement item is "power", the cell at another location is "buffer", and the input to that cell is "1". In this case, the replacement unit 503 refers to the cell replacement DB 220 and specifies an input fixing cell (replacement cell data 441) for fixing the input to the buffer to the power source (1). Then, the replacement unit 503 replaces the cells at other locations with the specified input fixed cells (replacement cell data 441).

In the following description, an operating part of the circuit TC to be measured may be referred to as an "operating block", and other parts other than the operating part may be referred to as a "non-operating block".

Here, if the cell of the non-operating block is replaced with the deleted cell, the connection net connected to the cell of the operating block will be in a floating state. Similarly, when a non-operating block cell is replaced with an input-fixed cell, the connection net connected to the operating block cell may become floating. The simulation does not work as expected when the inputs of the circuit are left floating.

For this reason, the replacing unit 503 may detect the cells connected to the connection net that is in the floating state among the cells of the operating block when the cells of the non-operating block are replaced with the replacement cells. Then, the replacement unit 503 may replace the detected cell with an input-fixed cell that fixes the input from the connection net that is in the floating state.

Specifically, for example, the replacement unit 503 refers to the cell replacement DB 220 and specifies an input-fixed cell that fixes the input from the connection net that is in the floating state according to the detected input to the cell. Then, the replacement unit 503 may replace the detected cell with the specified fixed input cell.

The creation unit 504 creates a netlist NL for operating characteristics measurement regarding the circuit to be measured TC based on the design data D after replacement. Here, the netlist NL for measuring operating characteristics is a netlist for measuring operating characteristics such as timing constraints and power regarding the circuit to be measured TC.

Specifically, for example, the creation unit 504 creates an LPE netlist by executing LPE using circuit diagram data sd after replacement and layout data ld after replacement. An LPE netlist is an example of a netlist NL for measuring operating characteristics. For example, an ordinary netlist includes parasitic element information for calculating delays in simulations, such as resistance and capacitance attached to wiring. is.

More specifically, for example, the creating unit 504 performs LVS on the circuit diagram data sd after replacement and the layout data ld after replacement. Then, the creating unit 504 creates an LPE netlist by executing LPE based on connection information and shape information obtained by executing LVS, and predetermined environmental conditions.

The connection information is information indicating connection relationships between cells and nets. The shape information is layout geometric information, and can specify, for example, the position of each component on the layout. Predetermined environmental conditions can be arbitrarily designated, and are represented, for example, by a combination of temperature and wiring variation conditions. The predetermined environmental conditions are obtained by the obtaining unit 501, for example.

Incidentally, when LVS is executed, in addition to connection information and shape information, correspondence information, for example, can be obtained. Correspondence information is information indicating which component (cell, net) in the circuit diagram data sd corresponds to which component in the layout data ld. A specific example of the correspondence information will be described later with reference to FIGS. 13 and 14. FIG.

The generator 505 uses the created netlist NL for measuring operating characteristics to create library data representing the operating characteristics of the circuit to be measured TC. Specifically, for example, the generator 505 uses the created LPE netlist to execute an existing lib measurement tool to generate library data representing the timing constraints, power, etc. of the circuit to be measured TC. .

In the lib measurement tool, in addition to the LPE netlist, for example, a setting file describing measurement patterns, tool settings, and measurement conditions required for various measurements is input. The measurement pattern and setting file are acquired by the acquisition unit 501, for example.

The output unit 506 outputs library data representing the operating characteristics of the generated circuit to be measured TC. The output format of the output unit 506 includes, for example, storage in a storage device such as the memory 302 and the disk 304, transmission to another computer (for example, the client device 202 shown in FIG. 2) via the communication I/F 305, and not shown. display, etc.

Specifically, for example, the output unit 506 may register the generated library data in a circuit library (not shown) in association with the circuit to be measured TC. Thereby, a circuit library used for LSI design can be created.

The output unit 506 may also output the created netlist NL for measuring operating characteristics. Specifically, for example, the output unit 506 may transmit the LPE netlist to another computer in association with the circuit to be measured TC. As a result, another computer can use the LPE netlist to generate library data representing the operating characteristics of the circuit to be measured TC.

(Specification example of operation block in circuit to be measured TC)
Next, a specific example of operation blocks in the circuit to be measured TC will be described with reference to FIGS. 6 to 10. FIG. First, an example of the circuit to be measured TC will be described with reference to FIG.

FIG. 6 is an explanatory diagram of an example of a circuit to be measured. In FIG. 6, a circuit to be measured 600 is an example of a circuit whose operating characteristics are to be measured. A circuit to be measured 600 shown in FIG. 6 corresponds to a visualization of the circuit diagram data sd regarding the circuit to be measured TC.

In the circuit under test 600, I0 to I9 indicate cell names. For example, cell I0 is an inverter. Cell I1 is an AND gate. a to i indicate names of connection nets. For example, connection net a connects cell I0 and cell I1. IN, TEST, and OUT indicate input/output pin names, respectively.

Next, a specific example of the results of functional simulation will be described with reference to FIG. Here, the result of the functional simulation executed using the circuit diagram data sd of the circuit under test 600 shown in FIG. 6 and the measurement pattern will be described as an example. Also, a case where the measurement item of the operating characteristics is the timing constraint will be described as an example.

FIG. 7 is an explanatory diagram showing a specific example of simulation results. In FIG. 7, a simulation result 700 indicates the result of functional simulation. A simulation result 700 shows changes in signals at each connection net and input/output pin. Here, it is assumed that the input signal TEST is always 0.

Next, a specific example of the active list will be described with reference to FIG. Here, an active list created from the simulation result 700 shown in FIG. 7 will be described as an example.

FIG. 8 is an explanatory diagram showing a specific example of the active list. In FIG. 8, an active list 800 is a list of information on nets that operate in the circuit under test 600 (see FIG. 6) in functional simulation.

In the active list 800, the first column indicates connection net names. The second column shows the state of the connection net. i indicates an input pin. o indicates an output pin. 1/0 indicates that they are always fixed to 1 or 0 respectively during the simulation period. x indicates a change during the simulation period.

Next, a specific example of connection information will be described with reference to FIG. Here, connection information obtained by executing LVS on the circuit diagram data sd and the layout data ld of the circuit to be measured 600 (see FIG. 6) will be described as an example.

FIG. 9 is an explanatory diagram showing a specific example of connection information. In FIG. 9, connection information 900 indicates the connection relationship between cells and nets in the circuit under test 600 (see FIG. 6). In the connection information 900 , the first column indicates the name of the cell used in the circuit under test 600 . The second and subsequent columns show net information connected to the cell shown in the first column.

Next, a specific example of operation blocks in the circuit under test 600 will be described with reference to FIG. Here, a case will be described in which operation blocks in the circuit under test 600 are specified based on the active list 800 shown in FIG. 8 and the connection information 900 shown in FIG.

FIG. 10 is an explanatory diagram showing a specific example of operation blocks. In FIG. 10 , an operation location identification result 1000 is an example of information that can identify an operation block in the measurement target circuit 600 . In the operation location identification result 1000, circled portions indicate connection nets (state x) and input/output pins that changed during the simulation period.

The circled portions are specified from the connection net (state x) that changed during the simulation period and the connection relationship between the connection net and the cell. Here, cells I0-I5 are identified as active blocks, and cells I6-I9 are identified as non-active blocks.

According to the operation location identification result 1000, since the connection nets e to i connected to the cells I6 to I9 did not change during the simulation period, the block including the cells I6 to I9 is an unnecessary block in terms of timing constraints. can identify something.

(First replacement example of a non-operating block in the circuit to be measured)
A first replacement example of non-operating blocks (cells I6 to I9) in circuit under test 600 will be described with reference to FIGS. 11 and 12. FIG. Here, replacement processing for the circuit diagram data sd regarding the circuit to be measured 600 will be described as an example. Also, the measurement item of the operating characteristics is the timing constraint.

11 and 12 are explanatory diagrams showing a first replacement example of non-operating blocks in the circuit under test. In FIG. 11, the cells I6 to I9 of the non-operating blocks in the circuit under measurement 600 are replaced with deletion cells 1101 to 1104, respectively, because the measurement items of the operating characteristics are timing constraints.

Taking the cell I6 as an example, the replacement unit 503 refers to the cell replacement DB 220, for example, and specifies the replacement cell data 421 representing the deletion cell of the same type (buffer) as the cell I6. Then, the replacement unit 503 replaces the cell I6 in the circuit under measurement 600 with the deletion cell 1101 using the specified replacement cell data 421 .

Here, regarding the connection net i, when the cell I9 is replaced with the deletion cell 1104, the input on the connection net i side of the cell I4 becomes a floating state. The floating state does not simulate as expected, so the input must be fixed. The connection net i is specified to be fixed to "0" from the simulation result 700 and the active list 800. FIG.

In FIG. 12, the replacement unit 503 detects the cell I4 connected to the connection net i which is in a floating state when the cell I9 is replaced with the deleted cell 1104. FIG. The replacing unit 503 then replaces the detected cell I4 with the input fixed cell 1201 that fixes the input from the connection net i.

More specifically, for example, the other connection net d connected to the input side of cell I4 is a connection net that changed during the simulation period. For this reason, the replacement unit 503 refers to the cell replacement DB 220, has the same type (OR gate) as the cell I4, and has two inputs, one of which is an external input, and the other of which is a ground ( 0) is specified as the replacement cell data 436 representing the input fixed cell to be fixed. Then, using the specified replacement cell data 436, the replacing section 503 replaces the cell I4 in the circuit under test 600 with the input fixed cell 1201. FIG.

Further, the replacing unit 503 also refers to the correspondence information 1300 and 1400 as shown in FIGS. A process of replacing cells in non-operating blocks with replacement cells is performed. Specifically, for example, the replacing unit 503 refers to the correspondence information 1300 and 1400 and replaces the cell at the same location as the circuit diagram data sd with the same replacement cell as the circuit diagram data sd.

13 and 14 are explanatory diagrams showing specific examples of correspondence information. In FIG. 13, the correspondence information 1300 indicates which cell in the circuit diagram data sd regarding the circuit under measurement 600 corresponds to which cell in the layout data ld regarding the circuit under measurement 600 . In the correspondence information 1300, the first column indicates the cell name of the circuit diagram data sd. The second column shows cell names of layout data ld.

In FIG. 14, the correspondence information 1400 indicates which connection net in the circuit diagram data sd regarding the circuit under measurement 600 corresponds to which connection net in the layout data ld regarding the circuit under measurement 600 . In the correspondence information 1400, the first column indicates the connection net name of the circuit diagram data sd. The second column shows the connection net name of the layout data ld.

According to the correspondence information 1300, 1400, it is possible to specify which part in the layout data ld corresponds to each part (cell, connection net) in the circuit diagram data sd. For this reason, the replacing unit 503 can replace the cells of the non-operating block with the replacement cells also for the layout data ld by the same processing procedure as for the circuit diagram data sd.

(Second replacement example of non-operating block in circuit to be measured)
A second replacement example of non-operating blocks (cells I6 to I9) in circuit under test 600 will be described with reference to FIG. Here, replacement processing for the circuit diagram data sd regarding the circuit to be measured 600 will be described as an example. Also, the measurement item of the operating characteristics is power. Also, the measurement pattern is assumed to be the same as in the case of timing constraints.

When the operating characteristic measurement item is power, if cells in non-operating blocks are replaced with deleted cells, leakage power cannot be measured correctly. Therefore, the replacing unit 503 replaces the non-operating block cell with an input fixing cell that disconnects the signal propagation in the cell and fixes the input. That is, the replacement unit 503 cuts off the connection net that does not operate and replaces it with a cell whose input is fixed.

FIG. 15 is an explanatory diagram of a second replacement example of non-operating blocks in the circuit to be measured. In FIG. 15, since the operating characteristic measurement item is power, the non-operating block cells I6 to I9 in the circuit under test 600 are replaced with input fixed cells 1501 to 1504, respectively.

Taking the cell I6 as an example, the replacement unit 503 refers to the cell replacement DB 220, for example, and selects an input fixation buffer that has the same type (buffer) as the cell I6 and fixes the input by cutting the signal propagation in the cell I6. The replacement cell data 431 representing the cell is specified. Using the specified replacement cell data 431 , replacement section 503 replaces cell I 6 in circuit under test 600 with input fixed cell 1501 .

For connection net i, when cell I9 is replaced with input fixed cell 1504, the input of cell I4 on the side of connection net i becomes floating. Therefore, the replacing unit 503 replaces the cell I4 with an input fixing cell 1505 that fixes the input from the connection net i to the ground (0).

(Example of operation of library development support device 201)
Next, an operation example of the library development support device 201 will be described with reference to FIGS. 16A, 16B and 16C.

16A, 16B, and 16C are explanatory diagrams showing an operation example of the library development support device 201. FIG. In FIG. 16A, first, the library development support device 201 executes LVS on the layout data 1601 and the circuit diagram data 1602 regarding the circuit TC to be measured. As a result, an LVS result 1603 including connection information (see, eg, FIG. 9), shape information, and correspondence information (see, eg, FIGS. 13 and 14) is output.

Further, when the measurement item of the operating characteristics is the timing constraint, the library development support device 201 performs function simulation (timing constraint) based on the circuit diagram data 1602 and the measurement pattern 1621 (timing constraint) shown in FIG. 16C. . As a result, an active list 1604 (timing constraints) for each measurement pattern 1621 is output.

When the operating characteristic measurement item is power, the library development support apparatus 201 performs function simulation (power) based on the circuit diagram data 1602 and the measurement pattern 1622 (power) shown in FIG. 16C. As a result, an active list 1605 (power) for each measurement pattern 1622 is output.

Next, library development support device 201 refers to cell replacement DB 220 based on layout data 1601, circuit diagram data 1602, LVS result 1603, active list 1604 (timing constraints), and active list 1605 (power) to generate data. Execute processing.

Here, an example of data processing will be described with reference to FIG. 17 .

FIG. 17 is an explanatory diagram showing an example of data processing by the library development support device 201. As shown in FIG. In FIG. 17, the library development support device 201 refers to the cell replacement DB 220 based on the LVS result 1603 and the active list 1604 (timing constraints) to process data (timing constraints) for layout data 1601 and circuit diagram data 1602 respectively. I do.

In data processing (timing constraint), for example, replacement with replacement cells as shown in FIGS. 11 and 12 is performed. As a result, layout data (timing constraints) 1601-1 after replacement and circuit diagram data (timing constraints) 1602-1 after replacement are output.

Further, the library development support device 201 refers to the cell replacement DB 220 based on the LVS result 1603 and the active list 1605 (power), and performs data processing (power) on the layout data 1601 and the circuit diagram data 1602 respectively. In data processing (power), for example, replacement with a replacement cell as shown in FIG. 15 is performed. As a result, layout data (power) 1601-2 after replacement and circuit diagram data (power) 1602-2 after replacement are output.

In FIG. 16B, the library development support device 201 performs LVS (timing constraints) on layout data (timing constraints) 1601-1 after replacement and circuit diagram data (timing constraints) 1602-1 after replacement. As a result, LVS results (timing constraints) 1611 including connection information, shape information and correspondence information (not shown) are output.

Further, the library development support device 201 performs LVS (power) on the replaced layout data (power) 1601-2 and the replaced circuit diagram data (power) 1602-2. As a result, an LVS result (power) 1612 including connection information, shape information and correspondence information (not shown) is output.

Next, the library development support device 201 executes LPE based on the LVS result (timing constraint) 1611 and environmental conditions 1613 . As a result, an LPE netlist (timing constraint) 1614 for each environmental condition 1613 is output.

Also, the library development support device 201 executes LPE based on the LVS result (power) 1612 and environmental conditions 1613 . As a result, an LPE netlist (power) 1615 for each environmental condition 1613 is output.

16C, the library development support device 201 uses an LPE netlist (timing constraints) 1614, measurement patterns (timing constraints) 1621, and setting files 1623 to execute the lib measurement tool. The setting file 1623 includes various tool settings and measurement conditions. The lib measurement tool recognizes the circuit to be measured TC, extracts the circuit to be measured, and measures the library data.

Also, the library development support device 201 uses the LPE netlist (power) 1615, the measurement pattern (power) 1622, and the setting file 1623 to execute the lib measurement tool. The lib measurement tool recognizes the target circuit TC and measures the library data.

As a result, library data 1624 is output to the circuit library lib. The library data 1624 is information representing the operating characteristics (timing constraints, power) of the circuit to be measured TC. Here, a specific processing procedure of the data processing processing of the library development support device 201 will be described.

FIG. 18 is a flow chart showing a data processing procedure of the library development support device 201. As shown in FIG. In the flowchart of FIG. 18, the library development support device 201 acquires circuit diagram data sd and layout data ld regarding the circuit to be measured TC (step S1801). Then, the library development support device 201 executes LVS on the acquired circuit diagram data sd and layout data ld (step S1802).

Next, the library development support device 201 performs functional simulation using the acquired circuit diagram data sd and the measurement pattern (step S1803). Then, the library development support apparatus 201 identifies operation blocks in the circuit to be measured TC based on the result of the functional simulation and the result of the LVS (connection information) (step S1804).

Next, the library development support device 201 executes replacement processing on the acquired circuit diagram data sd (step S1805). The replacement process is a process of replacing a cell in a non-operating block, which is different from an operating block, with a replacement cell in the circuit to be measured TC. A specific processing procedure of the replacement processing for the circuit diagram data sd will be described later with reference to FIG.

Next, the library development support apparatus 201 executes replacement processing on the obtained layout data ld (step S1806). The specific processing procedure of the replacement processing for the layout data ld is the same as the specific processing procedure for the replacement processing for the circuit diagram data sd shown in FIG. 19, so illustration and description are omitted. However, the replacement process for the layout data ld is performed using, for example, the LVS result (correspondence information).

Then, the library development support device 201 outputs the circuit diagram data sd after replacement and the layout data ld after replacement (step S1807), and ends the series of processing according to this flowchart. Note that the processing in steps S1802 and S1803 may be executed in the opposite order or in parallel. Also, the processing in steps S1805 and S1806 may be executed in the opposite order or in parallel.

Next, a specific processing procedure of the replacement processing in step S1805 shown in FIG. 18 will be described with reference to FIG.

FIG. 19 is a flowchart illustrating an example of a specific processing procedure for replacement processing. In the flowchart of FIG. 19, first, the library development support device 201 refers to the cell replacement DB 220 and selects a non-operating block cell different from the specified operating block for replacement specified according to the operating characteristic measurement item. Replace with a cell (step S1901).

Next, the library development support device 201 detects the cells connected to the connection net in the floating state among the cells of the operation block (step S1902). Then, the library development support device 201 refers to the cell replacement DB 220, replaces the detected cell with an input-fixed cell that fixes the input from the connection net that is in the floating state (step S1903), and calls replacement processing. return to the previous step.

As a result, the library development support device 201 performs processing such as deleting circuit blocks unnecessary for library development and suppressing signal propagation unnecessary for library development from the input data for LPE netlist creation. be able to.

(Example)
Next, an embodiment using a memory circuit as the circuit to be measured TC will be described.

FIG. 20 is an explanatory diagram showing an example of a memory circuit. 20, memory circuit 2000 includes a memory cell array 2001, a sense amplifier 2002, a decode circuit 2003, an input/output circuit 2004 and a control circuit 2005. FIG. In the memory cell array 2001, memory cells MC holding data are arranged in rows and columns.

A sense amplifier 2002 amplifies data when reading data from the memory cell array 2001 . Decode circuit 2003 determines which row of memory cell array 2001 is selected. The input/output circuit 2004 inputs and outputs data. A control circuit 2005 controls the entire memory circuit 2000 .

D indicates write data. Q indicates read data. A indicates address data for selecting a memory cell MC. WR indicates a write/read selection signal. CK indicates a clock signal that serves as a reference for operation. Here, it is assumed that the measurement item of the operating characteristics is the timing constraint. In this case, the library development support device 201 performs an operation simulation regarding timing constraints of the memory circuit 2000 .

FIG. 21 is an explanatory diagram showing the flow of read data in the memory circuit. The library development support device 201 can, for example, observe the current value of each memory cell MC and determine a cell whose current value exceeds a certain threshold as an operating cell. Further, the library development support device 201 observes the read delay, and from the bits of the maximum delay path and the minimum delay path, the sense amplifiers 2002-1 and 2002-2 and the input/output circuits 2004-1 and 2004-2 of the corresponding bits. can be specified.

The library development support device 201 combines these pieces of information with LVS output information (LVS results) to identify inoperative memory cells MC and sense amplifiers 2002 and input/output circuits 2004 that do not affect delay measurement. Non-operating memory cells MC are cells outside the ranges 2101, 2102, 2103 and 2104, for example.

Sense amplifiers 2002 that do not affect delay measurement are sense amplifiers other than sense amplifiers 2002-1 and 2002-2. Input/output circuits 2004 that do not affect delay measurement are input/output circuits other than input/output circuits 2004-1 and 2004-2. Then, the library development support device 201 refers to the cell replacement DB 220 and replaces the specified memory cell MC or the like with a replacement cell necessary for minimum connection so as not to affect the operation.

FIG. 22 is an explanatory diagram of an example of a memory circuit after replacement. In FIG. 22, non-operating blocks 2201 and 2202 are removed from memory circuit 2000 . However, in FIG. 22, deletion of non-operational blocks 2201 and 2202 is represented by hatching. In non-operational blocks 2201 and 2202, for example, each cell is replaced with a cell having only wiring data necessary for connection.

Next, it is assumed that the measurement item of the operating characteristics is power. In this case, the library development support device 201 performs an operation simulation regarding power consumption of the memory circuit 2000 . In power measurement, if blocks that do not operate are deleted, leakage power cannot be measured correctly, so processing different from timing constraints is required.

FIG. 23 is an explanatory diagram of an example of a decoding circuit. In FIG. 23, it is assumed that dec[m−2], WL[n−1], and WL[n−2] of the decoding circuit 2003 are connection nets that do not operate. Here, the input to gate A, which drives WL[n-1], has not changed, but the input to the preceding gate B has changed.

Therefore, the library development support device 201 replaces the gate A with a cell whose input is grounded. Also, for WL[n-2], the input to gate C does not change. Therefore, the library development support device 201 replaces the input of the gate C with a cell in which the input is grounded. Also, for dec[m−2], the input to gate D does not change. Therefore, the library development support device 201 replaces the input of the gate D with a cell in which the input is grounded.

FIG. 24 is an explanatory diagram of an example of a decoding circuit after replacement. In FIG. 24, gate A in decode circuit 2003 is replaced with input fixed cell 2401 . Also, the gate C is replaced with an input fixed cell 2402 . Also, the gate D is replaced with the input fixed cell 2403 .

In this way, according to the library development support device 201, by replacing the input of the non-operating gate in the decoding circuit 2003 with a cell fixed to the ground (or power supply voltage), signal propagation is reduced and the operating area is reduced. can be done. As a result, the execution time of the lib measurement tool and the resource usage can be reduced without degrading the library measurement accuracy.

As described above, according to the library development support device 201 according to the embodiment, the design data D regarding the circuit to be measured TC is acquired, and based on the result of the operation simulation using the acquired design data D, Operational blocks of the circuit TC can be identified. Then, according to the library development support device 201, the storage unit 510 (for example, the cell replacement DB 220) is referred to, and the cell of the non-operating block different from the specified operating block in the design data D is measured for operating characteristics. It is possible to create a netlist NL for measuring the operating characteristics of the circuit to be measured TC based on the design data D after replacement with replacement cells specified according to the items.

As a result, the design data D is processed to reduce the execution time and resource usage required for creating the operating characteristic measurement netlist NL for the circuit to be measured TC. be able to. Also, the amount of data of the generated netlist NL itself can be reduced. Further, for example, in macro design, hierarchical design is performed in which basic gates are combined to form functional blocks, and a plurality of such functional blocks are combined to design a macro that implements a required function. Here, by preparing replacement cells for basic gates in advance, when processing data, it is only necessary to replace basic gates related to non-operating blocks with replacement cells according to the operation. simplification is possible.

Further, according to the library development support device 201, when the measurement item of the operating characteristics is the timing constraint, the storage unit 510 is referred to, the deletion cell for deleting the cell of the non-operating block is specified, and the cell of the non-operating block is specified. Cells can be replaced with identified deleted cells.

As a result, it is possible to delete the circuit blocks unnecessary for the measurement of the operating characteristics from the design data D, thereby reducing the execution time and resource usage required for creating the netlist NL for measuring the operating characteristics.

Further, according to the library development support device 201, when the operating characteristic measurement item is power, the storage unit 510 is referred to, and an input fixing cell whose input is fixed by disconnecting signal propagation in the cell of the non-operating block is specified. , and the cells of the non-working block can be replaced with the specified fixed input cells.

As a result, it is possible to eliminate from the design data D the connection relationships between the elements that are unnecessary for the measurement of the operating characteristics, thereby suppressing signal propagation that is unnecessary for the measurement of the operating characteristics. As a result, unnecessary signal propagation is not determined for measurement of operating characteristics, and the execution time and amount of resources used to create netlist NL for measuring operating characteristics can be reduced.

Further, according to the library development support device 201, among the cells of the operating block, the cells connected to the connection net which becomes floating when the cells of the non-operating block are replaced with the replacement cells are detected, and the detected cells can be replaced by an input fix cell that fixes the input from the connection net.

As a result, it is possible to prevent the connection nets connected to the cells of the operation block from becoming floating by deleting circuit blocks that are not necessary for measuring the operating characteristics or by deleting the connection relationships between elements. can. Therefore, it is possible to prevent the operation of the circuit to be measured TC from becoming unstable when measuring the operating characteristics.

Further, according to the library development support device 201, the design data D including the circuit diagram data sd regarding the circuit to be measured TC and the layout data ld regarding the circuit to be measured TC are acquired, and the circuit diagram data sd and the measurement pattern are used. Based on the result of the operation simulation, it is possible to identify the operation block of the circuit to be measured TC.

As a result, by using the circuit diagram data sd, which has a smaller amount of data than the layout data ld, to simulate the operation of the circuit to be measured TC, it is possible to speed up the process of identifying the operation block.

Further, according to the library development support device 201, using the created netlist NL for measuring operating characteristics, library data representing the operating characteristics of the circuit to be measured TC can be generated, and the generated library data can be output. .

Thereby, a circuit library can be generated. In addition, since the data amount of the netlist NL itself is reduced when generating the library data, for example, the execution time and resources used in the lib measurement tool are reduced, and the cost required for library development can be reduced.

Further, according to the library development support device 201, it is possible to output the created netlist NL for measuring operating characteristics.

As a result, another computer can use the LPE netlist to generate library data representing the operating characteristics of the circuit to be measured TC.

Therefore, according to the library development support device 201, circuit blocks and connections unnecessary for library development are not included in the input data for creating the LPE netlist. Execution time and amount of resources used can be reduced. In addition, since an optimized LPE netlist is created according to the measurement items of the library data (operating characteristics), the execution time and amount of resources used to measure the library data can be reduced, and circuit library development costs can be reduced. can be reduced.

The library development support method described in this embodiment can be implemented by executing a prepared program on a computer such as a personal computer or a workstation. The library development support program is recorded in a computer-readable recording medium such as a hard disk, flexible disk, CD-ROM, DVD, USB memory, etc., and is executed by being read from the recording medium by a computer. Also, the library development support program may be distributed via a network such as the Internet.

Further, the library development support device 201 (information processing device 101) described in the present embodiment can also be realized by a specific application IC such as an ASIC (Application Specific Integrated Circuit) or a PLD (Programmable Logic Device) such as an FPGA. can be done.

Further, the following additional remarks are disclosed with respect to the above-described embodiment.

(Appendix 1) Acquiring design data on the circuit to be measured for operating characteristics,
based on a result of an operation simulation using the acquired design data, identifying an operating portion of the circuit to be measured;
replacement specified according to the measurement item of the operating characteristics, by referring to a storage unit storing a plurality of replacement cells, in the design data, cells at other locations different from the specified operating location; replace the cell with
creating a netlist for measuring operating characteristics of the circuit to be measured based on the design data after replacement;
A library development support program characterized by causing a computer to execute processing.

(Appendix 2) The process of replacing
When the measurement item is a timing constraint, referring to the storage unit, identifying a deletion cell for deleting the cell at the other location, and replacing the cell at the other location with the identified deletion cell. The library development support program according to appendix 1, characterized by:

(Appendix 3) The process of replacing
When the measurement item is power, the storage unit is referenced to identify an input fixing cell that disconnects signal propagation in the cell at the other location to fix the input, and the cell at the other location is identified. 3. The library development support program according to appendix 1 or 2, wherein the input fixed cell is substituted.

(Appendix 4) Detecting cells connected to connection nets that are in a floating state when the cells in the other locations are replaced with the replacement cells, among the cells in the operating location,
replacing the detected cell with an input-fixing cell that fixes the input from the connection net;
4. The library development support program according to any one of appendices 1 to 3, characterized by causing the computer to execute the processing.

(Appendix 5) The design data includes circuit diagram data related to the circuit to be measured and layout data related to the circuit to be measured,
The process of specifying
5. The method according to any one of appendices 1 to 4, wherein a portion of the circuit to be measured that operates is specified based on a result of an operation simulation using the circuit diagram data and the measurement pattern. Library development support program.

(Appendix 6) generating library data representing the operating characteristics of the circuit to be measured using the created netlist for measuring operating characteristics;
outputting the generated library data;
6. The library development support program according to any one of appendices 1 to 5, characterized in that the processing is executed by the computer.

(Appendix 7) The library development support program according to any one of Appendices 1 to 6, characterized by causing the computer to execute a process of outputting the created netlist for measuring operating characteristics.

(Appendix 8) Acquiring design data on the circuit to be measured for operating characteristics,
based on a result of an operation simulation using the acquired design data, identifying an operating portion of the circuit to be measured;
replacement specified according to the measurement item of the operating characteristics, by referring to a storage unit storing a plurality of replacement cells, in the design data, cells at other locations different from the specified operating location; replace the cell with
creating a netlist for measuring operating characteristics of the circuit to be measured based on the design data after replacement;
A library development support method, wherein a computer executes processing.

(Appendix 9) Acquiring design data on the circuit to be measured for operating characteristics,
based on a result of an operation simulation using the acquired design data, identifying an operating portion of the circuit to be measured;
The replacement specified in accordance with the measurement item of the operating characteristic by referring to a storage unit storing a plurality of replacement cells, and replacing the cell at a location different from the specified operating location in the design data. replace the cell with
creating a netlist for measuring operating characteristics of the circuit to be measured based on the design data after replacement;
An information processing apparatus comprising a control unit.

101 information processing device 110, 510 storage unit 120 operating part 130 non-operating part 131 cell 200 information processing system 201 library development support device 202 client device 210 network 220 cell replacement DB
300 Bus 301 CPU
302 memory 303 disk drive 304 disk 305 communication I/F
306 portable recording medium I/F
307 portable recording medium 501 acquisition unit 502 identification unit 503 replacement unit 504 creation unit 505 generation unit 506 output unit 600, TC circuit to be measured 700 simulation results 800, 1604, 1605 active list 900 connection information 1000 operation location identification results 1101, 1102 , 1103, 1104 Deleted cells 1201, 1501, 1502, 1503, 1504, 1505, 2401, 2402, 2403 Input fixed cells 1300, 1400 Correspondence information 1601, ld Layout data 1602, sd Circuit diagram data 1603, 1611, 1612 LVS results 1613 environmental conditions 1614, 1615 LPE netlist 1621, 1622 measurement pattern 1623 setting file 1624 library data 2000 memory circuit 2001 memory cell array 2002 sense amplifier 2003 decoding circuit 2004 input/output circuit 2005 control circuit D design data

Claims (8)

Acquiring design data about the circuit to be measured for operating characteristics,
based on a result of an operation simulation using the acquired design data, identifying an operating portion of the circuit to be measured;
replacement specified according to the measurement item of the operating characteristics, by referring to a storage unit storing a plurality of replacement cells, in the design data, cells at other locations different from the specified operating location; replace the cell with
creating a netlist for measuring operating characteristics of the circuit to be measured based on the design data after replacement;
A library development support program characterized by causing a computer to execute processing. The process of replacing
When the measurement item is a timing constraint, referring to the storage unit, identifying a deletion cell for deleting the cell at the other location, and replacing the cell at the other location with the identified deletion cell. 2. The library development support program according to claim 1, characterized by: The process of replacing
When the measurement item is power, the storage unit is referenced to identify an input fixing cell that disconnects signal propagation in the cell at the other location to fix the input, and the cell at the other location is identified. 3. The library development support program according to claim 1, wherein said fixed input cell is substituted. detecting a cell connected to a connection net that is in a floating state when the cell in the other portion is replaced with the cell for replacement, among the cells in the operating portion;
replacing the detected cell with an input-fixing cell that fixes the input from the connection net;
4. The library development support program according to any one of claims 1 to 3, causing the computer to execute processing. the design data includes circuit diagram data about the circuit to be measured and layout data about the circuit to be measured;
The process of specifying
5. The circuit according to any one of claims 1 to 4, wherein an operating portion of the circuit to be measured is specified based on a result of an operation simulation using the circuit diagram data and the measurement pattern. library development support program. generating library data representing the operating characteristics of the circuit to be measured using the created netlist for measuring operating characteristics;
outputting the generated library data;
6. The library development support program according to any one of claims 1 to 5, causing the computer to execute processing. Acquiring design data about the circuit to be measured for operating characteristics,
based on a result of an operation simulation using the acquired design data, identifying an operating portion of the circuit to be measured;
replacement specified according to the measurement item of the operating characteristics, by referring to a storage unit storing a plurality of replacement cells, in the design data, cells at other locations different from the specified operating location; replace the cell with
creating a netlist for measuring operating characteristics of the circuit to be measured based on the design data after replacement;
A library development support method, characterized in that processing is executed by a computer. Acquiring design data about the circuit to be measured for operating characteristics,
based on a result of an operation simulation using the acquired design data, identifying an operating portion of the circuit to be measured;
replacement specified according to the measurement item of the operating characteristics, by referring to a storage unit storing a plurality of replacement cells, in the design data, cells at other locations different from the specified operating location; replace the cell with
creating a netlist for measuring operating characteristics of the circuit to be measured based on the design data after replacement;
An information processing apparatus comprising a control unit.

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