Via structures in multi-layer printed circuit boards (PCBs) and packages are studied using an equivalent transmission line model. Thus, transmission line theories, such as characteristic impedance and propagation constant, can be used to characterize the performance of via structures in a signal path. The closed-form expressions of R, L, G, C parameters of the equivalent transmission line model...

This paper describes a simulation-based analysis of a printed circuit board (PCB) testing process. The PCBs are used in a defense application and the testing process is fairly complex. Boards are mounted on a test unit in batches and go through three thermal test cycles. As boards fail testing during the thermal cycling, operators can either replace the failed boards at fixed points during the ...

Printed circuit boards (PCBs) are currently being dumped in landfills or incinerated which is causing a serious environmental harm in the form of toxic gases or leached hazardous compounds. PCBs contain high amounts of precious metals; about 20 wt% copper, 0.04 wt% gold, 0.15 wt% silver, and 0.01 wt% palladium. The extraction of these metals from PCBs is both profitable and environmentally wort...

Printed circuit boards (PCBs) are a valuable source of raw materials for metal recycling considering that base concentration analyses have confirmed PCB powders multimetallic in nature and contain high concentrations Cu, Zn, Ni, Fe. Given minerals not renewable resources, these metals can be recycled through hydrometallurgical processes. In this study, we determined 2 M sulfuric acid, 0.55 MPa ...

The electronics industry includes: the manufacture of: passive components (resistors, capacitors, inductors); semiconductor components (discretes, integrated circuits); printed circuit boards (single and multilayer boards); and printed wiring assemblies. This document addresses the environmental issues associated with the latter three manufacturing processes. The manufacturing of passive compon...

The design to market time of printed circuit boards (PCBs) is a function of individual cycle times of different processes that comprise the production of the PCBs. Production of a family of PCBs with common electronic component layout, composition and interconnections can also be greatly reduced by implementing the principle of Reverse Engineering (RE). This will reduce the PCBs cycle time and ...

The light emitting diode (LED) is widely used in modern solid-state lighting applications, and its output efficiency is closely related to the submounts' material properties. Most submounts used today, such as low-power printed circuit boards (PCBs) or high-power metal core printed circuit boards (MCPCBs), are not transparent and seriously decrease the output light extraction. To meet the requi...

Wasted printed circuit boards, PCBs, contain not only valuable metals such as Cu, Au, etc., but also smelting-repellent components Al, Br, and Sb. The latter should be removed before feeding them to the smelting process. In this study, we applied processes a pretreatment (i) heating screening remove devices on (ii) roasting remove/decompose Br Sb from (iii) two-stage selective grinding concentr...

Electronic waste (e-waste) is one of the fastest increasing waste streams worldwide due to unprecedented growth of the electronics industry, rapid obsolescence and subsequent disposal of electronic devices. Printed circuit boards (PCBs), the central component of electronic devices, are highly complex. PCBs are an important resource of metals, and contain substantial amounts of copper, tin, lead...

This paper addresses the problem of schedulingN printed circuit boards (PCBs) on a single machine equippedwith an automatic component interchangemechanism. Assume that the total number of di€ erent components required to process all N PCBs is greater than the capacity of the spool. If the requisite components are not on the spool, then one or more component switches must occur before the PCB ca...