Industry Directory | Manufacturer
QISMT Co.,ltd provide a full SMT assembly line solutions, including SMT reflow oven, wave soldering machine, pick and place machine, solder paste printer, PCB loader, PCB unloader, SMT inspection machine, SMT assembly line
Technical Library | 2024-07-24 00:51:44.0
A blade server system (BSS) utilizes voltage regulator modules (VRMs), in the form of quad flat no-lead (QFN) devices, to provide power distribution to various components on the system board. Depending on the power requirements of the circuit, these VRMs can be mounted as single devices or banked together. In addition, the power density of the VRM can be high enough to warrant heat dissipation through the use of a heat sink. Typically, at field conditions (FCs), the BSS are powered on and off up to four times per day, with their ambient temperature cycling between 258C and 808C. This cyclical temperature gradient drives inelastic strain in the solder joints due to the coefficient of thermal expansion (CTE) mismatch between the QFN and the circuit card. In addition, the heat sink, coupled with the QFN and the circuit card, can induce additional inelastic solder joint strain, resulting in early solder joint fatigue failure. To understand the effect of the heat sink mounting, a FEM (finite element model of four QFNs mounted to a BSS circuit card was developed. The model was exercised to calculate the maximum strain energy in a critical joint due to cyclic strain, and the results were compared for a QFN with and without a heat sink. It was determined that the presence of the heat sink did contribute to higher strain energy and therefore could lead to earlier joint failure. Although the presence of the heat sink is required, careful design of the mounting should be employed to provide lateral slip, essentially decoupling the heat sink from the QFN joint strain. Details of the modeling and results, along with DIC (digital image correlation) measurements of heat sink lateral slip, are presented.
Career Center | Tampa, Florida USA | Accounting/Finance,Production,Purchasing
Reptron Manufacturing Services needs an experienced Assistant Buyer/Planner for their large contract manufacturing facility. The qualified candidate must be a self-starter with an understanding of PC board manufacturing and component procurement with
The Innovation in logistics for SMT components Technical data: •Count accuracy: more than 99,9 % •Cycle time: less than 10 sec •Weight: 450 kg •Dimensions: 70x75x220 cm •Reel diameter: max. 38 cm •Reel height: max. 10 cm Your advantages with OC-SCA
Solder joint inspection of bottom-side PCBs Intelligent Inspection of Solder Joints, THT and SMD Components Today, the industry standard quality assurance in electronics production is automatic optical inspection (AOI) of SMD components on printed
Career Center | Van Nuys, California USA | Production
We are an ISO 9000, AS 9100, ISO 13485 and NASA certified; Quick Turn, High Reliability, Contract Manufacturer of PCB assemblies, located in the San Fernando Valley. We serve the aerospace, military, space, medical and telecommunications and other L
The long-term inspection solution for wave, reflow, pre-reflow and selective soldering. In the manufacturing of electronic assemblies, optimization of the production processes is a major factor in the success of producing to the high demands of qual
Overview • higher performance than standard 68000 • delivered with fully automated test-bench • complete set of tests The D68000 soft core is binary-compatible with the industry standard 68000 32-bit microcoprocessor. It has a 16-bit data b
New Equipment | Test Equipment
This product is NEW USD $6960.00 Megger BITE 2 Megger Model # BITE 2 Catalog # 246002B Battery Impedance Test Equipment Determines condition of lead-acid and NiCd cells up to 7000 Ah On-board Pass/Warning/Fail indications Robust,
New Equipment | Selective Soldering
The PLUS of Flexibility and Precision. Time plays a key role in modern electronic production. With the SelectLine SEHO developed a selective soldering system featuring miniwave processes. Its revolutionary design convinces with highest precision and
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