Degradation Analysis of Thick Film Chip Resistors

2009 ◽  
Author(s):  
Bhanu Sood ◽  
Diganta Das ◽  
Michael H. Azarian ◽  
Michael Pecht
Keyword(s):  
Thick Film ◽  
Printed Circuit Board ◽  
Negative Resistance ◽  
Circuit Board ◽  
High Humidity ◽  
Circuit Boards ◽  
Chemical Modifications ◽  
Current Leakage ◽  
Printed Circuit ◽  
Degradation Analysis

Abstract Negative resistance drift in thick film chip resistors in high temperature and high humidity application conditions was investigated. This paper reports on the investigation of possible causes including formation of current leakage paths on the printed circuit board, delamination between the resistor protective coating and laser trim, and the possibility of silver migration or copper dendrite formation. Analysis was performed on a set of circuit boards exhibiting failures due to this phenomenon. Electrical tests after mechanical and chemical modifications showed that the drift was most likely caused by moisture ingress that created a conductive path across the laser trim.

The Use of Polymer Thick Film for Making Printed Circuit Boards

1982 ◽  
Vol 1 (1) ◽  
pp. 22-23 ◽  
Author(s):  
F.W. Martin
Keyword(s):  
Thick Film ◽  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
Electronics Industry ◽  
Circuit Board ◽  
Technical Knowledge ◽  
Circuit Boards ◽  
Printed Circuit ◽  
The Cost

The electronics industry is facing a situation in which the cost of electronic functions is dropping continuously while the cost of interconnecting the functions by traditional means, especially through the use of printed circuit boards, continues to rise. Polymer thick film is one proven approach to reversing the trend of rising interconnection costs. It is relatively easy for the typical printed circuit board manufacturer to convert to or adapt polymer thick film because he has most of the necessary equipment, technical knowledge and personnel.

Dielectric Breakdown in Printed Circuit Boards at Elevated Temperatures

1996 ◽  
Author(s):  
P. Singh ◽  
G.T. Galyon ◽  
J. Obrzut ◽  
W.A. Alpaugh
Keyword(s):  
Experimental Data ◽  
Thermal Degradation ◽  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
Elevated Temperatures ◽  
Dielectric Breakdown ◽  
Circuit Board ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Data Matching

Abstract A time delayed dielectric breakdown in printed circuit boards, operating at temperatures below the epoxy resin insulation thermo-electrical limits, is reported. The safe temperature-voltage operating regime was estimated and related to the glass-rubber transition (To) of printed circuit board dielectric. The TG was measured using DSC and compared with that determined from electrical conductivity of the laminate in the glassy and rubbery state. A failure model was developed and fitted to the experimental data matching a localized thermal degradation of the dielectric and time dependency. The model is based on localized heating of an insulation resistance defect that under certain voltage bias can exceed the TG, thus, initiating thermal degradation of the resin. The model agrees well with the experimental data and indicates that the failure rate and truncation time beyond which the probability of failure becomes insignificant, decreases with increasing glass-rubber transition temperature.

scholarly journals A model for the reflection of terahertz signals from printed circuit board surfaces

2018 ◽  
Vol 10 (2) ◽  
pp. 179-186 ◽  
Author(s):  
Alexander Fricke ◽  
Mounir Achir ◽  
Philippe Le Bars ◽  
Thomas Kürner
Keyword(s):  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
Simulated Annealing Algorithm ◽  
Specular Reflection ◽  
Circuit Board ◽  
Network Analyzer ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Propagation Modeling ◽  
Annealing Algorithm

AbstractBased on vector network analyzer Measurements, a model for the specular reflection behavior of printed circuit boards in the Terahertz range has been derived. It has been calibrated to suit the behavior of the measurements using a simulated annealing algorithm. The model has been tailored for integration to ray-tracing-based propagation modeling.

scholarly journals NotchPUF: Printed Circuit Board PUF Based on Microstrip Notch Filter

Cryptography ◽  
2020 ◽  
Vol 4 (2) ◽  
pp. 11
Author(s):  
Mitchell Martin ◽  
Jim Plusquellic
Keyword(s):  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
Statistical Tests ◽  
Notch Filter ◽  
Circuit Board ◽  
Circuit Boards ◽  
Printed Circuit ◽  
In Series ◽  
Commercial Off The Shelf ◽  
Using Data

Physical Unclonable Functions (PUFs) are primitives that are designed to leverage naturally occurring variations to produce a random bitstring. Current PUF designs are typically implemented in silicon or utilize variations found in commercial off-the-shelf (COTS) parts. Because of this, existing designs are insufficient for the authentication of Printed Circuit Boards (PCBs). In this paper, we propose a novel PUF design that leverages board variations in a manufactured PCB to generate unique and stable IDs for each PCB. In particular, a single copper trace is used as a source of randomness for bitstring generation. The trace connects three notch filter structures in series, each of which is designed to reject specific but separate frequencies. The bitstrings generated using data measured from a set of PCBs are analyzed using statistical tests to illustrate that high levels of uniqueness and randomness are achievable.

Downsizing an automotive junction box based on large current-carrying printed-circuit board optimization

2016 ◽  
Vol 231 (2) ◽  
pp. 267-278 ◽  
Author(s):  
Hansang Lim ◽  
Do-Hwan Jung ◽  
Geono Kwon ◽  
Young Jong Lee ◽  
Jun Seo Park
Keyword(s):  
Power Distribution ◽  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
Circuit Board ◽  
Installation Space ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Overcurrent Protection ◽  
Large Current ◽  
Analytical Estimation

An automotive junction box distributes electric power to electric systems installed in a vehicle with overcurrent protection. As a larger number of electric systems are installed, the junction box is equipped with more components, functionalities and connections. However, owing to the fuse accessibility, its installation space is so restricted that a downsized design is required for the junction box. The junction box is composed of small signal circuitry for control and monitoring, and large current-carrying circuitry for power distribution which includes many parallel traces. Because of these unique features, widely used techniques for downsizing printed-circuit boards are not applicable. Also, there is no rule for designing large current-carrying parallel traces, and it is difficult to optimize the size of the printed-circuit board for the automotive junction box. This paper presents the design rules for a printed-circuit board when downsizing a junction box. First, the layout strategy for the power distribution components is presented, which is determined by the sum of the squares of the currents flowing through connector pairs. Then, the thermal effects of parallel traces are simulated for different conditions by using thermal analysis software. Based on the results, an analytical estimation of the additional temperature rises due to parallel traces and rules for a thermally effective arrangement of the parallel traces are presented.

Future paper based printed circuit boards for green electronics: fabrication and life cycle assessment

2014 ◽  
Vol 7 (11) ◽  
pp. 3674-3682 ◽  
Author(s):  
Jingping Liu ◽  
Cheng Yang ◽  
Haoyi Wu ◽  
Ziyin Lin ◽  
Zhexu Zhang ◽  
...  
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Environmental Impact ◽  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
Circuit Board ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Future Paper ◽  
Printing Paper

A multilayer printed circuit board (PCB) can be fabricated using commercially available printing paper, which shows comparable functionalities with the conventional organic PCBs but 100 times lower environmental impact.

scholarly journals A User Made Thick Film System

1980 ◽  
Vol 6 (3-4) ◽  
pp. 151-158 ◽  
Author(s):  
M. Honore ◽  
R. Govaearts ◽  
D. Hostens ◽  
B. Bouw ◽  
B. Matton ◽  
...  
Keyword(s):  
Thick Film ◽  
Printed Circuit Board ◽  
State Of The Art ◽  
The State ◽  
Circuit Board ◽  
Film System ◽  
Printed Circuit ◽  
The Subject

This paper describes the state of the art in the development of a polymer based printed circuit board (PCB) compatible resistor ink system. The subject is treated from the standpoint of the manufacturer who, up to now, supplied himself with PCB circuitry.

Advanced Materials for Printed Circuit Boards

1987 ◽  
Vol 108 ◽  
Author(s):  
David Wei Wang
Keyword(s):  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
High Reliability ◽  
Circuit Board ◽  
Advanced Materials ◽  
Impregnation Method ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Worldwide Production ◽  
Board Industry

The printed circuit board is an integral part of the electronic packaging hierarchy. Its use began more than 40 years ago, and the demand for printed circuit boards has increased in parallel with the growth of the electronics industry.[1] According to a recent forecast, the worldwide production of printed circuit boards will reach to over 19 billion U.S. dollars' worth by 1990.[2] With continuing demands for more interconnections, the multilayer circuit board industry is experiencing its fastest growth rate. Boards with more than 20 inner planes of circuitry are being manufactured with high reliability.Based on dollar values, more than 90% of the circuit boards produced are in the rigid board category, where starting materials are based on thermosetting prepregs produced by a solution impregnation method. This article is a review of materials currently used in rigid composites.

Sign in / Sign up

Export Citation Format

Share Document