JPH10111887A - Lsi development man-hour prediction supporting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To support accurate man-hour estimation with less human factors in a system relating to the estimation of design man-hour or the like generated in an LSI development job. SOLUTION: This system is provided with a central processing unit 100, a storage device 110, an input device 120 and an output device 130. The storage device 110 is provided with a basic data table 112 for which ranking is performed by the specifications of an LSI relating to development and parameters corresponding to ranks are defined and a man-hour prediction approximate expression file 113 storing a man-hour prediction approximate expression for obtaining predicted man-hour. The man-hour prediction approximate expression is constituted of an approximate expression using at least one parameter for which the fact that correlation is present with the predicted man-hour is already known.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for estimating a contracted amount of LSI development work, in which when the estimated amount is calculated based on the man-hours required for development and design work, the amount of man-hours generated is reduced before starting development work. And a method for accurately predicting.

[0002]

2. Description of the Related Art In general, in the development and design of an LSI (Large Scale Integrated Circuit), it is usual that a plurality of skilled circuit designers decide the part in charge of each person and proceed with the development. At this time, in this industry, a circuit design contractor is contracted from a contractor in charge of circuit assembly to design preparation work-logic basic design-logic design-layout design-evaluation test, and through the development work, customer A design document including a design drawing is submitted to a contractor in charge of assembling a circuit. Then, the assembler is paid to the contractor for the contract work.

[0003] At this time, if a contractor undertakes design work, if the number of development man-hours related to the contract is estimated to be insufficient, the actual design man-hour exceeds the estimated man-hour, and a profit or loss is recorded. Conversely, if you overestimate the development man-hours, you will not have price competitiveness with other companies in the industry, and you will not be able to receive orders for contract work. Against this background, the contractor determines the design specifications of the LSI to be developed based on the design specifications provided by the assembler, and then the contractor's manager makes intuition for each person. The estimated man-hours are estimated based on the experience and experience, and the estimated amount is calculated by multiplying the man-hour unit price (amount), and presented to the assembler.

[0004] Depending on the qualities of the manager in charge of the above-mentioned man-hour estimation, there are extremely many factors that influence the load of the LSI development work, and these factors may be related to each other, so that the man-hour load can be accurately estimated. Instead, an underestimate or an overestimate may occur. further,
At the present time, when estimating a similar LSI development work, the result of the previous estimation cannot be accurately reflected, and the objective estimation work has not been established at present.

[0005] The inventor of the present invention, which is engaged in contract development, conducts such work by referring to a man-hour estimation system in another industry in order to improve the accuracy of the man-hour estimation work.
Tried to divert to development work. As an invention related to man-hour estimation in another industry, an invention related to Japanese Patent Application Laid-Open No. 8-161374 is disclosed.

[0006]

However, the estimation data processing apparatus described in the above-mentioned gazettes and the like is based on a completed design document, and the type and use of a used component described in the design document and known in advance. It is intended to estimate the quantity of parts as a factor of the estimated amount. On the other hand, LSI
In the contract work, the man-hours required for circuit design are to be estimated as a factor of the estimated amount. Due to this difference, in the LSI design work, when estimating, there is no completed design document, etc., and since the design content is gradually determined in the design process, the man-hour required for the design is It is difficult to determine in advance. Therefore, unlike the above-mentioned publications in which the factors of the estimated amount are clear, it is necessary to extract and estimate other factors. Also,
Since the extracted factors are entangled with each other, it is necessary to extract and correlate an appropriate factor, and it has been difficult to divert the invention. Accordingly, the present invention has been made in view of the above circumstances, and has as its object to provide a development man-hour prediction support system for supporting prediction of man-hours occurring in LSI development work.

[0007]

In order to achieve this object, an invention according to a first aspect of the present invention is a development man-hour prediction support system for supporting estimation of man-hours occurring in LSI development work. A storage device that stores programs and data, a central processing device that executes a program stored in the storage device and performs support processing for man-hour prediction,
An input device for the central processing unit, and an output device for outputting a predicted man-hour report or a quote as a result of data processing, wherein the storage device ranks according to the specification of the LSI to be developed, and has parameters according to the rank. A basic data table that defines the estimated man-hours, comprising a man-hour prediction approximate expression file storing a man-hour prediction approximate expression for obtaining the estimated man-hours, wherein the man-hour prediction approximate expression is known to have a correlation with the estimated man-hours. The gist is that it is constituted by an approximate expression using one parameter. Further, the invention according to the second aspect of the present invention is characterized in that the parameters in the first aspect are defined in at least one LSI specification described below. A) Number of cells for creating circuit diagrams in logic basic cell design b) Number of cells for simulation in logic basic cell design c) Number of master cells and slice cells in logic basic cell design d) Types of logic diagram interface in logic design E ) Verification level in logic design F) Number of created vectors and supply vectors in logic design g) Number of critical paths specified in layout design h) Number of surge standards in evaluation test i) Number of latch-up standards in evaluation test Nu) Years of follow-up for mass production in follow-up.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings. Note that the present embodiment predicts the number of development steps of an LSI for a specific application, but is of course not limited to the following embodiment.

FIG. 1 is a diagram showing an example of a hardware configuration used in an embodiment of the present invention. In FIG. 1, a development man-hour prediction system (1) according to the present embodiment includes a central processing unit (100), an external storage device (110), an input device (120), and an output device (130).

The central processing unit (100) has at least C
It comprises a PU (101) and a main memory (102). The external storage device (110) is composed of, for example, a hard disk device, and the external storage device (110) has a program file ( 11
1), a basic data table (112), a man-hour prediction approximate expression file (113), and a man-hour prediction data file (114) for storing predicted man-hours. The input device (120) is an input device such as a keyboard. The output device (130) outputs a man-hour prediction result to a CRT or a printer. Hereinafter, the contents of the basic data table (112) stored in the external storage device (110), the man-hour prediction approximate expression file (113), and the man-hour prediction data file (114) for storing the estimated man-hours will be described. I do.

(A) Man-hour prediction approximate expression file (113)
(Separation of work items) First, the work related to the LSI consignment is separated into a plurality of work items. In general, sorting is mainly performed in consideration of two points, that is, whether or not it can be contracted and accepted and whether or not it is a sorting unit for which man-hours can be predicted. An example of classification is shown in FIG. 9 and will be described. In FIG. 9, what is described in the column of classification is that the work process is roughly divided into groups, and what is described in the column of item is the extracted work item of the man-hour calculation execution unit.

First, regarding the group classification, in addition to the four steps of specification design, logic design, layout design, and evaluation test of commonly used processes, logic basic cell design for creating a basic cell for performing logic design, analog Add follow-up equivalent to cell design and post-design maintenance. Furthermore, design preparations and evaluation preparations necessary for the development of LSIs in new fields and other difficulties in grouping are also added.

Next, actual work items in each group classification will be described. As shown in FIG. 9, in the column of classification “design preparation”, only one of the work items, “design preparation”, was extracted. In the column of specification design classification, two work items were extracted: a specification study for designing LSI functions and an electrical property study for designing electrical characteristics such as power consumption and output transition time. . In the column of the logic basic cell design classification, the work items include circuit design, layout design, and parameter extraction for obtaining cell delay information. In the category of logic design, the work items are basic logic design for assembling logic on a desk, creating a logic diagram for inputting drawings of logic assembled on a desk by CAD, and creating inputs and expected values for logic verification. Simulation vector design and logic simulation were extracted. In the column of the layout design classification, the work items include a layout specification for determining a floor plan and the like, a layout design for actual arrangement and wiring, and a parameter extraction for obtaining delay information due to wiring and the like. In the column of the category of preparation for evaluation, the work items extracted were preliminary examination, evaluation specifications, creation of a test program for using an LSI tester, and creation of an evaluation jig. When the classification is in the column of the evaluation test, the work items are an ES level evaluation that performs up to the determination of ES shipment, a CS level evaluation that performs up to the determination of CS shipment,
The electrostatic withstand capability evaluation for examining the withstand capability when a high voltage is instantaneously applied to the LSI due to static electricity or the like, and the sorted shipment were extracted. In the column where the classification is “follow”, two work items, mass production follow and customer follow, were extracted. In the other columns of the classification, the work items are items that cannot be classified into the above classifications.

(A) Configuration of basic data table (112) (selection of basic data) In selecting basic data of the basic data table,
Needless to say, this is the basis for calculating the man-hour correctly, but it is necessary to select one that is not subjective in order to eliminate the variation in the estimated man-hour due to human factors of the manager of the contractor. In consideration of this, the work item required for man-hour calculation is selected.

The common items will be described. The common basic data necessary for man-hour calculation of many types of LSIs include, of course, the number of pins A1, the gate size A2, and the like, but in addition, the total number of memory bits A3 and the total number of analog section elements A4 are selected. . This is an LS with built-in memory and analog
This corresponds to the rapid increase of I in recent years. Memory is simply calculated from the number of bits and the design difficulty and test vector /
It is extracted because it is easy to estimate the time. The development man-hours related to analog are difficult to calculate with other items, and it is easy to estimate based on the number of elements, and the accuracy can be improved to some extent.

The logic basic cell related items will be described. As for the logic basic cell, since the circuit configuration is almost determined because of the basic cell, it is not appropriate to consider the difficulty due to the scale or the like in the circuit design. Therefore, as the extraction items, the number B1 of circuit diagram creation cells, the number B2 of simulation cells, and the number B3 of function descriptions are selected. Although the layout of the logic basic cell can be originally made only by the number of cells to be created, for example, in LSI design, in many cases, the only difference is the size of the output transistor and the others are exactly the same. In this case, since the accuracy of man-hour calculation is not improved only by the number of created cells, two items of the number of master cells B4 and the number of slice cells B5 are used. That is, the number of master cells B4 is the number of cells for which the layout creation work must be performed for a certain amount or more, and the number of slice cells B5 is the number of cells that can be completed based on the master cells for a work of a certain amount or less (mainly correction). is there. In addition, with respect to the layout, there are many operations in which only a few layers are changed for a cell group that has already been created. In this regard, the revised mask number B6 accompanying the change is used as basic data and used as a parameter representing the amount of work. Since the contents of work are greatly different between the internal cell and the I / O cell, respective items are prepared for each.
Since most of the simulation parameter extraction after the completion of the circuit design and the layout design depends on the CAD input operation, the number of DLF extraction cells B10 and the number of TV extraction cells B11 that directly indicate the number of operations are selected.

The logical design related items will be described. Conventionally, in logic design, man-hours are generally obtained simply from the number of gates A2. However, in this case, man-hours are greatly different when design resources are diverted in the past. Large-scale LSI
Now, it is almost normal to design with multiple people and multiple teams, and it is essential to reflect this. Therefore, this logic design is an intellectual production of devising and assembling the basic logic on a desk, and in this regard, the number C1 of the basic logic design gates is simply selected. Creating a logic diagram is a process of inputting a logic diagram into a CAD for LSI design. In this regard, the number of gates C2 and a logic diagram interface C3 are required as basic data. Further, both C2 and C3 have different levels of difficulty in the logic diagram at the top of the LSI and other logic diagrams. Therefore, C
2, each of C3 is divided into two regions of a top and a block. In addition, since the logic synthesis is performed while considering the whole, it is sufficient if there is only one item of the total number of logic synthesis gates C7 without dividing. In the simulation vector design, the creation vector C5 is simply selected. However, since the difficulty is greatly different between the top and the other, the basic data is divided into the top and the block. The logic simulation is to execute a simulation to find out a small defect at a logic design level, and requires a vector number C6 to be supplied as a simulation vector in addition to the created vector. Also, a simulation verification level C4 is of course required. These also divide the basic data into two parts: top and block.

The layout design related items will be described. Layout design uses CA using logic basic cells.
D means automatic placement and routing and correction of the output result. In addition to the above common basic data, a basic assignment of a pin assignment presentation D1 indicating whether or not to work, a delay information extraction D3, and a delivery level D4 are selected. Also, a critical path designation D2 is entered as basic data indicating the degree of difficulty. This is the amount of work to reduce the delay amount of the node where the delay is a problem in the placement and routing, and it has been empirically known that this optimization work greatly affects the work time.

The evaluation / test related items will be described.
Work items related to the evaluation mainly include an evaluation of electrical characteristics, an evaluation of an electrostatic immunity, and a sorting shipment. In the electrical characteristic evaluation, the number of measurements E1, the number of DC items E2, the total number of function vectors E3, and the number of AC items E4 are selected. This is because the electrical characteristics evaluation method has been almost determined in the current LSI, and it has been determined that basic data for estimating only the workload is sufficient. However, since the man-hour varies depending on the evaluation level, that is, the level of the ES shipment or the level of the CS shipment, it is determined for each. Although the evaluation of the electrostatic withstand voltage is usually considered based on the number of times of measurement, it is impossible to predict the number of times of measurement, including for the purpose of analysis when a defect actually occurs. Therefore, the standard numbers E13 and E14 to be cleared are added to the basic data in addition to the number of pins, and the calculation based on this is performed. As a result, it is possible to eliminate individual variations due to the conventional estimation of the number of measurements.

The follow-related items will be described. Follow-up refers to assisting in troubleshooting a mass-production factory that occurs after the completion of LSI development, answering questions from customers, and analyzing defective products. In many cases, these are not known until the actual work comes, and in the past, they were hardly calculated. In this example, in order to introduce the concept of the maintenance fee in the calculation and make it a general man-hour, as the basic data, the follow-up years F1,
F2 was extracted.

FIGS. 3 to 8 show data extracted as described above. What is described in the parameter columns of FIGS. 3 to 8 is the basic data. Basic data is 6
A1 to A5 which are divided and are common items are shown in FIG.
FIG. 4 shows B1 to B11 which are logic basic cell related items.
FIG. 5 shows logical design related items C1 to C11, FIG. 6 shows layout design related items D1 to D4, FIG. 7 shows evaluation / test related items E1 to E16, and follow-related items. F1 and F2 are shown in FIG.

(C) Configuration of the basic data table (112) (table creation) The basic data table (112) is a conversion table for facilitating extraction of calculation parameters. Is uniquely determined as a parameter for calculation. As for the basic data selected as described above, it is a table in which values that can be taken by the data of each item are divided into several sections. As shown in FIG. 3, for example, regarding the number of pins A1 which is a representative factor of the LSI scale of the common item, “80 pins or less”, “81 to 12”
0 pins, 121 pins to 200 pins, and 201 pins to 300 pins. Then, the parameters are determined as “0”, “1”, “2”, and “3”. Therefore, for example, for an 80-pin LSI, the parameter is “0”.
In the case of 256 pins, the parameter is “3”.

Incidentally, there is a type such as the average logical diagram interface C3 which is classified by a form instead of a numerical value. The average logic diagram interface C3 and the average verification level C4 are items related to the block design. However, since there are usually a plurality of blocks, they cannot be simply divided. If an attempt is made to extract each block, it becomes complicated, and in many cases, even the number of blocks is unknown at the calculation stage. Therefore, here, the item is one for all blocks,
It is determined to which block the block average belongs.

(D) Man-hour prediction approximate expression file (113)
Configuration (Derivation of Man-hour Prediction Approximation Formula) In constructing the man-hour prediction approximation expression file (113), unlike simple work, LS has many intelligent production processes.
In the I design, since the man-hours also depend on the ability of the individual and the difficulty that cannot be expressed by a numerical value, the configuration is made by paying attention to the fact that a complicated calculation formula has little meaning. In this case, a simple calculation formula has a greater merit that the concept of calculation of man-hour calculation becomes clear.

In the LSI design, man-hours required for development can be largely divided into an initial examination time and an actual development time. The initial examination time is various investigations and preliminary examinations performed prior to actual development, and the man-hour is substantially the same regardless of the type of LSI to be developed. Further, the actual development time can be represented by man-hours in proportion to the calculation parameters of each basic data table if the division can be appropriately divided. For example, the logic design-logic diagram creation man-hour T52 is calculated by the following equation (1).
Can be represented by This is also referred to as the logical design 5 in FIG.
-2 Shown in the column of logic diagram creation.

[0026]

T52 = 50 + 50 × C2 × C3 + 25 × A2
× C8 + 150 × C7

The first term in Equation 1 is that 50
Indicates time. The second term is the time required for inputting the gate level logic diagram of the block, and is proportional to the number of logic gates in charge and the logic diagram interface. The third term is the time required to enter the top gate level logic diagram and is proportional to the total number of logic gates and the logic diagram interface.
The fourth term is the time for automatically generating a logic diagram by logic synthesis, and is proportional to the number of logic synthesis gates.

The layout design-layout design man-hour T62 can be expressed by the following equation (2). Also,
This is shown in the column of 6-2 layout design in the layout design of FIG.

[0029]

T62 = 100 + 50 × A1 + 25 × D2 + 25 × D4

The first term in Equation 2 is that 10
Represents 0 hours. The second and third terms are work times that vary depending on the designated number of critical paths and the delivery level.

Further, follow-mass production follow man-hour T91
Can be represented by the following Equation 3. Also, this is shown in the column of 9-1 Mass production follow of FIG. 9.

[0032]

## EQU3 ## T91 = 200 + 100 × F1

The first term in Equation 3 is 200 in the initial study.
The second term indicates the maintenance fee per year. FIG. 9 shows a list of the approximate expressions defined in this manner.

Next, the operation of the development man-hour prediction support using the system of this embodiment will be described in time series.

FIG. 2 shows a processing flow of man-hour calculation using the man-hour prediction support system according to the present embodiment. First, among the specification items in the design stage, such as the power consumption, the chip size, the number of pins, the number of gates, and the like of the LSI for which the development man-hour is predicted, the items shown in FIGS. 3 to 8 are extracted.

Next, calculation parameters are selected for the extracted items. That is, for each of the extracted items described in FIGS. 3 to 8, a parameter is selected from the value of the specification. Thereby, “0”, “1”, “2”, “3”, or “X” is displayed in the parameter column shown in FIGS.
Is selected. Here, it was thought that “X” did not appear from the viewpoint of the normal technical level at the time of developing the man-hour prediction support system, but with the development of LSI technology thereafter, specifications that had not been predicted appeared. At that time,
It takes a value such as "4", "5", "6" or the like.

Next, the parameters of the basic data selected as described above are substituted into the approximate expression shown in FIG. Thereby, the estimated man-hours for each item described in the classification column and the item column of FIG. 9 are selected.

Next, the estimated man-hours for each item calculated as described above are added. Thereby, the estimated man-hours for each category are calculated in the estimated man-hour column shown in FIG. 10, and the sum thereof is calculated in the total column. Next, after the result is stored in the man-hour prediction data file (114), it is output to a CRT or a printer by an output device (130) as needed.

In this way, the man-hours required for LSI development are predicted. If the predicted value and the actual value are significantly different from each other, correction is necessary. When there is a major technological progress or a change in the design method, it is necessary to change the basic data and the table. However, such a change is usually rare, and the approximation formula Tnn stored in the man-hour approximation formula file (113) is used.
It is enough to review (n is a natural number). why? For example, the logic design-logic diagram creation man-hour T represented by Formula 1
52 is a constant at the head of each term (first term = 50, second term = 5
0, the third term = 25, the fourth term = 150) may be changed according to the actual results.

[0040]

The following is a calculation example. It is assumed that the specification of the LSI for development is as follows. Total number of logic gates = 20K Logic block design Number of logic gates in charge of our company = 5K Logic block design average logic diagram interface = Logic diagram Logic top design logic diagram interface = Specifications Logic synthesis gate number = 0 In this case, each parameter is as shown in Fig. 3. From FIG. 5 and FIG. 5, A2 = 2, C2 = 1, C3 = 1, C7 = 0, and C8 = 2. For example, if the logic design-logic diagram creation man-hour is obtained, the above equation 1 (No5-2 in FIG. 9) is used. If substituted, it can be calculated as 200 hours. These tasks, namely,
The parameters of the other items shown in FIG. 9 are obtained from the basic data tables shown in FIGS. 3 to 8 and are substituted into the calculation formulas shown in FIG. 9 to calculate each item and perform an addition operation. Then, by adding these, the total man-hour required for the development of the target LSI is obtained. The form on which this was output is shown in FIG. Further, the actual estimated amount is, for example, 1
If it is 5000 yen per hour, this will be multiplied.

[0041]

According to the invention described in claim 1 of the present invention, it is difficult to grasp the number of development steps at the time of estimation.
It is possible to accurately estimate man-hours related to the I development work. In addition, since the specification of the LSI is not directly used in the man-hour calculation but is calculated through a parameter, the calculation can be performed regardless of the specification of the LSI having various values. Also, since there are no human factors, there is no variation among assessors. Next, according to the invention described in claim 2 of the present invention, in addition to the effects of the invention described in claim 1, it is not clear even what has conventionally been a factor in LSI development man-hours. Man-hour calculations can now be performed in practice.

[Brief description of the drawings]

FIG. 1 is a hardware configuration diagram of a system according to an embodiment.

FIG. 2 is a flowchart of man-hour prediction using the system of the present embodiment.

FIG. 3 is a table showing a data table of common items of a basic data file.

FIG. 4 is a chart showing a data table of logic basic cell related items of a basic data file.

FIG. 5 is a table showing a data table of logical design related items of a basic data file.

FIG. 6 is a table showing a data table of layout design related items of a basic data file.

FIG. 7 is a chart showing a data table of evaluation / test related items of a basic data file.

FIG. 8 is a chart showing a data table of follow-related items in a basic data file.

FIG. 9 is a chart showing an approximate expression of a man-hour prediction approximate expression file.

FIG. 10 is a chart showing man-hour prediction result data of a man-hour prediction data file.

[Explanation of symbols]

 1 Development man-hour prediction support system according to the present embodiment 100 Central processing unit 110 External storage device 120 Input device 130 Output device

Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/82 C

Claims (2)

[Claims] 1. A development man-hour prediction support system for supporting estimation of man-hours occurring in LSI development work, comprising: a storage device for storing programs and data; and a man-hour by executing a program stored in the storage device. A central processing unit for performing a prediction support process, an input device for the central processing unit, and an output device for outputting a prediction man-hour or a quotation as a result of the data processing; A basic data table that ranks according to the specifications and defines parameters according to the rank, and a man-hour prediction approximation formula file storing a man-hour prediction approximation formula for obtaining a prediction man-hour, wherein the man-hour prediction approximation formula is between Characterized by an approximate expression using at least one parameter known to have a correlation in System. 2. The method according to claim 1, wherein the parameter is at least one of the following:
2. The work man-hour prediction support system according to claim 1, wherein the system is defined by an LSI specification. A) Number of cells for creating circuit diagrams in logic basic cell design b) Number of cells for simulation in logic basic cell design c) Number of master cells and slice cells in logic basic cell design d) Types of logic diagram interface in logic design E ) Verification level in logic design F) Number of created vectors and supply vectors in logic design g) Number of critical paths specified in layout design h) Number of surge standards in evaluation test i) Number of latch-up standards in evaluation test Nu) Years of follow-up for mass production in follow-up.