ScanINSPECT VPI is a fully integrated, stand-alone process control, measurement and inspection and programming workstation for use in process setup and new product introduction in the PCB or Hybrid Microcircuit assembly industries. ScanINSPECT VPI
Littelfuse PulseGuard® ESD Suppressors offer extremely low capacitance which makes them ideal for use in high-speed data circuits (IEEE 1394, USB 2.0, HDMI, DVI, etc.). Available in single-line and multi-line packages, they provide ESD protection whi
Nanovea Mechanical Testers provide unmatched multi-function Nano and Micro/Macro modules on a single platform. Both the Nano and Micro/Macro modules include scratch tester, hardness tester and wear tester modes providing the widest and most user frie
Technical Library | 2013-01-24 19:16:35.0
The electronics industry has mainly adopted the higher melting point Sn3Ag0.5Cu solder alloys for lead-free reflow soldering applications. For applications where temperature sensitive components and boards are used this has created a need to develop low melting point lead-free alloy solder pastes. Tin-bismuth and tin-bismuth-silver containing alloys were used to address the temperature issue with development done on Sn58Bi, Sn57.6Bi0.4Ag, Sn57Bi1Ag lead-free solder alloy pastes. Investigations included paste printing studies, reflow and wetting analysis on different substrates and board surface finishes and head-in-pillow paste performance in addition to paste-in-hole reflow tests. Voiding was also investigated on tin-bismuth and tin-bismuth-silver versus Sn3Ag0.5Cu soldered QFN/MLF/BTC components. Mechanical bond strength testing was also done comparing Sn58Bi, Sn37Pb and Sn3Ag0.5Cu soldered components. The results of the work are reported.
Technical Library | 2019-10-03 14:27:01.0
Knowing how package warpage changes over temperature is a critical variable in order to assemble reliable surface mount attached technology. Component and component or component and board surfaces must stay relatively flat with one another or surface mount defects, such as head-in-pillow, open joints, bridged joints, stretched joints, etc. may occur. Initial package flatness can be affected by numerous aspects of the component manufacturing and design. However, change in shape over temperature is primarily driven by CTE mismatch between the different materials in the package. Thus material CTE is a critical factor in package design. When analyzing or modeling package warpage, one may assume that the package receives heat evenly on all sides, when in production this may not be the case. Thus, in order to understand how temperature uniformity can affect the warpage of a package, a case study of package warpage versus different heating spreads is performed.Packages used in the case study have larger form factors, so that the effect of non-uniformity can be more readily quantified within each package. Small and thin packages are less prone to issues with package temperature variation, due to the ability for the heat to conduct through the package material and make up for uneven sources of heat. Multiple packages and multiple package form factors are measured for warpage via a shadow moiré technique while being heated and cooled through reflow profiles matching real world production conditions. Heating of the package is adjusted to compare an evenly heated package to one that is heated unevenly and has poor temperature uniformity between package surfaces. The warpage is measured dynamically as the package is heated and cooled. Conclusions are drawn as to how the role of uneven temperature spread affects the package warpage.
Technical Library | 2022-10-31 17:30:40.0
This paper presents a quantitative analysis of solder joint reliability data for lead-free Sn-Ag-Cu (SAC) and mixed assembly (SnPb + SAC) circuit boards based on an extensive, but non-exhaustive, collection of thermal cycling test results. The assembled database covers life test results under multiple test conditions and for a variety of components: conventional SMT (LCCCs, resistors), Ball Grid Arrays, Chip Scale Packages (CSPs), wafer-level CSPs, and flip-chip assemblies with and without underfill. First-order life correlations are developed for SAC assemblies under thermal cycling conditions. The results of this analysis are put in perspective with the correlation of life test results for SnPb control assemblies. Fatigue life correlations show different slopes for SAC versus SnPb assemblies, suggesting opposite reliability trends under low or high stress conditions. The paper also presents an analysis of the effect of Pb contamination and board finish on lead-free solder joint reliability. Last, test data are presented to compare the life of mixed solder assemblies to that of standard SnPb assemblies for a wide variety of area-array components. The trend analysis compares the life of area-array assemblies with: 1) SAC balls and SAC or SnPb paste; 2) SnPb balls assembled with SAC or SnPb paste.
280°C). Unlike PTFE based microwave materials, no special through-hole treatments or handling procedures are required. RO4003C was designed with a dielectric constant of 3.38. The RO4350B has a dielectric constant of 3.48 and is UL94V-0 rated. RO445
New Equipment | Solder Materials
Superior Drop Shock Performance AND Thermal Cycling Reliability Current Industry Dilemma The standard set of Pb-free alloys has a dramatic trade-off between thermal cycling and drop testing. Additionally, all these SAC alloys are far inferior to
Used SMT Equipment | In-Circuit Testers
Rohde & Schwarz CMD60-B1-B3-B4-B6-B41-B44-B61-K61 Digital Radiocommunication Tester R&S CMD60 Digital Radiocommunication Tester. (formerly marketed as Tektronix CMD60) Production High production output at low investment for test equipmen
Used SMT Equipment | In-Circuit Testers
-178 dBc/Hz Noise floor lowering method: Two-channel cross correlation Frequency and power test: Parameters: Frequency and power Sweep type: DC power voltage or DC control voltage Transient tests: Parameters: Frequency, phas
