IPC9850_Surface Mount Equipment Characterization.pdf - 第2页
IPC-9850 Official Proposal May 2001 2 INDEX [This will be generated by the typesetter when the document is published; it’s included just to assist reviewers and should not be commented against.] 1 Introduction 1.1 Scope …
IPC-9850
Surface Mount Equipment Characterization
Assembly Equipment Sub-Committee (5-41)
Official Proposal
May 2001
Published by IPC
2215 Sanders Road
Northbrook, IL 60062-6135
847/509-9700
Fax 847/509-9798
URL: http://www.ipc.org
IPC-9850
Official Proposal
May 2001
2
INDEX [This will be generated by the typesetter when the document is published; it’s included just to assist
reviewers and should not be commented against.]
1 Introduction
1.1 Scope
1.2 Purpose
1.3 Background
1.4 Implementation
1.4.1 Characterization Limitations
1.4.2 Binding Requirements
1.4.3 Test Components
1.4.4 Test Panels
1.4.5 Measurement
1.4.5.1 Equipment
1.4.5.2 Reporting
1.5 Forms
1.6 Data Methods
1.7 Terms and Definitions
1.8 Units of Measurement
2. Referenced Documents
3 Placement Performance Metric
3.1 Placement Performance Form IPC-9850-F1
3.1.1 General Performance
3.1.2 Performance Validation
3.2 Characterization Methodology
3.2.1 Background
3.2.1.1 Component-to-Component Variability
3.2.1.2 Machine’s Component Accomodation
3.2.1.3 Panel-to-Panel Variability
3.3 Machine Performance Parameters
3.3.1 Test Conditions
3.3.1.1 Number of Heads/Spindles
3.3.1.2 Type of Heads/Spindles
3.3.1.3 Type of Camera
3.3.1.4 Number of Feeders/Trays
3.3.1.5 Type of Nozzles
3.3.1.6 Number of Nozzles
3.3.1.7 Number of Panels Built
3.3.1.8 Number of Parts Per Panel
3.3.2 Time-Based Parameters
3.3.2.1 Build Time
3.3.2.2 Transfer Time (T
t
)
3.3.2.3 Total Tact Time
3.3.2.4 Tact Time
3.3.2.5 Net Throughput
3.3.3 CMM Measured Parameters
3.3.3.1 Repeatability
3.3.3.2 Accuracy
3.3.3.2.1 Spec limits for Cpk
3.3.3.2.2 Cpk for Termination-to-Land Coverage
4 Attribute Defect Rate and Reliability Performance
Metric-- Form IPC-9850-F2
4.1 Attribute Defect Rate
4.2 Reliability Parameters
4.2.1 Mean Placements Between Assists (MPBA)
4.2.2 Mean Time To Recover from Assists (MTTR
a
)
4.2.3 Mean Placements Between Failures (MPBF)
4.2.4 Mean Time To Repair Failures (MTTR
f
)
4.2.5 Total Time
4.2.6 Non-Scheduled Time
4.2.7 Operations Time
4.2.8 Equipment Dependent Uptime
4.2.9 Preventative Maintenance (PM) Time
4.2.10 Mispick Rate (in PPM)
4.3 Reporting Sites
4.3.1 Number of Machines
4.3.2 Total Number of Placements
4.3.3 Total Pickup Attempts
5 Measurement Capability Verification–Form IPC-
9850-F3
5.1 Gauge Repeatability and Reproducibility Capability
5.2 Accuracy Capability
6 Test Vehicles
6.1 Placement Verification PVP Specifications
6.2 PVP Carrier Specifications
6.3 Glass Slug Specifications
6.4 Sticky Media Application
6.5 Placement Program
6.5.1 1608C Component
6.5.2 SOIC-16 Component
6.5.3 QFP-100 and BGA-228 Slug
6.5.4 QFP-208 Slug
7 Forms and Diagrams
Appendices
A. Capability Indexes
B. Specification Limits for Cpk Values
C. Guidelines for Adhesive Used for Machine Capability
Testing
D. Suggested Methodologies for Measuring
Components using an Optical CMM
E. Component Locations for Placement Verification
Panel Population
F. Component Location for Accuracy Verification Panel
G. How to Perform a GR&R Test
H. Instruction for Using the Gauge R&R Spreadsheet
I. Placement Verification Panel Carrier
J. Component Location for GR&R evaluation
K. Instruction for Using The ‘Termination-to-Land
Calculations.xls’ spreadsheet
IPC-9850
Official Proposal
May 2001
3
1 Introduction
1.1 Scope
This standard establishes the procedures to characterize machine placement capability of surface mount assembly
equipment in specification documents, as well as in documentation used to verify a specific machine’s placement
capability conformance to the specification, while maintaining a placement accuracy to placement speed
relationship.
1.2 Purpose
IPC-9850 has been developed to standardize the parameters, measurement procedures, and the methodologies used
for the specification, evaluation, and continuing verification of assembly equipment characterization parameters.
These standardized tools shall be used to develop and report the information called out in this standard.
1.3 Background
With the proliferation of Surface Mount Technology (SMT), placement equipment users have struggled with the
question of which machine will perform best in a given manufacturing environment. The advantage of the SMT
assembly process to rapidly place components in precise alignment to the land patterns on the printed wiring board
(PWB) was the initial yardstick by which machines were selected. Machines that could place components the
quickest and with the least amount of scrap were considered the best.
Initially, the most common evaluation method was placement yield. For this evaluation, a machine is made to
populate a large number of the user product where visible placement errors are counted as defects. Machines with
the least defects and the most robust operation were considered best. The high yield and reliability of modern SMT
placement systems require that very large amounts of data be collected to meaningfully assess yield and reliability.
This standard provides new tools for gauging the yield and reliability of placement equipment yet presents
performance results in the traditional metrics.
In addition to the high yield and reliability expected of modern placement equipment, the SMT assembly process
has become significantly more demanding. Components have decreased in size, component terminations are smaller,
and placement locations have moved closer together. All this while the number of components on the PWB and
product volumes have increased significantly. Placement equipment must now place components more rapidly and
with extreme precision to be financially viable. This has made requirements on placement machines more
demanding.
Historically, placement equipment vendors have selected their own parameters and methodologies to present the
specification of their machines’ throughput and placement capabilities. The many representations of this information
have made the comparison between similar types of placement machines very difficult. To obtain comparable data,
users have been forced to conduct on-location evaluations of various machines under the same conditions. This type
of methodology is very time consuming for users and very capital intensive for suppliers.
This standard simplifies the evaluation process by standardizing the performance parameters that describe the
placement machines’ capabilities. It also couples placement throughput and placement quality so speed and accuracy
parameters are dependent on each other. This standard also specifies the methodologies by which the capability
parameters are measured. This reduces potential user-vendor friction created when the user believes the equipment
is not functioning properly. The methodologies specified herein are consistent and verifiable, thus providing
common-ground-methodologies between users and vendors.
These methodologies were achieved by separating machine performance from the rest of the SMT process variables,
which include paste printing, component quality, packaging type and PWB quality. The speed and quality evaluation
methods of this standard specify that measurements will be made by placement of standardized components into
sticky media on clear glass panels. Experience shows that surface mount equipment must perform well on sticky
media before it can perform well in production. Furthermore, improved process capability on sticky tape usually
translates into enhanced process capability in production. Although this method does not provide information that
can be utilized to perfectly predict production quality, this methodology was selected in order to remove as much of
the variation as possible between facilities, products, process, and operators.
While the ultimate goal is to evaluate a machine’s capability to place components in paste on actual PWBs, it is not
currently possible to make such measurements at the required precision and speed. It is anticipated that future in-line