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Packaging Issues for SiGe Circuits
Published in John D. Cressler, Circuits and Applications Using Silicon Heterostructure Devices, 2018
Kyutae Lim, Stephane Pinel, Joy Laskar
The main problem with through-hole devices was their size. Furthermore, their performance in high frequencies was quite limited. The trend in PCB manufacturing was to increase density while decreasing board area and increasing signal frequencies. Through-hole devices did not easily allow this to happen. In the 1980s, through-hole devices began to give way to a new packaging technology called surface mount technology (SMT) [5]. The leads from these packages mount directly to rectangular pads on the surface of the PCBs. They did not require holes to be drilled into the PWBs. As a result, the width of the leads could be smaller and the spacing between the leads (lead pitch) could be decreased. This allowed for a package with the same number of pins as a traditional through-hole device to be significantly smaller, despite the fact that these devices were made with the same materials as the through-hole devices. Common surface mount devices included the plastic leaded chip carrier (PLCC) and the small outline integrated circuit (SOIC). In recent years, the quad flat pack (QFP) has become a predominant fine pitch, high lead count package solution. Figure 13.1 illustrates most of the previous topologies and Figure 13.2 shows some popular packaging devices used through the 1980s and 1990s [1].
Package form factors and families
Published in Andrea Chen, Randy Hsiao-Yu Lo, Semiconductor Packaging, 2016
Andrea Chen, Randy Hsiao-Yu Lo
The quad packages with J-leads are generally known as plastic leaded chip carrier (PLCC) and have lead counts up to 84. Those with gull-wing leads are known as quad flat pack (QFP) packages. The QFP subgroup has several variations, depending on body thickness and lead pitch, with lead counts ranging up to 256. QFP packages are also available with thermal enhancement, such as an exposed heat spreader.
Interconnections and Connectors
Published in Michael Pecht, Handbook of Electronic Package Design, 2018
The PLCC is used in multicontact sizes in less expensive IC applications. It is basically common to applications that do not generate much heat, because of its plastic construction. CER-DIPs are ceramic DIP for through hole mounting, and ceramic flatpacks and quadpacks are surface mounted. PLCCs are generally found in J-lead configurations.
Reliability Modeling of Reservoir-Based Tidal Power Plants for Determination of Spinning Reserve in Renewable Energy-based Power Systems
Published in Electric Power Components and Systems, 2019
Mostafa Mirzadeh, Mohsen Simab, Amir Ghaedi
The PLCC value considering four cases at different lead times and risk criteria are calculated and illustrated in Table 3. The capability of the power system to meet the required loads increases by scheduling some tidal units to its generation sector. However, the initial tidal height, lead time values and the risk criteria value can affect the value of PLCC. In this study, IPLCC as an available index calculated from PLCC is determined and discussed for different cases to more deeply investigate the effects of tidal units in comparison with the conventional ones. The obtained results are presented in Table 4. Based on the table, the scheduling tidal plants with low initial water height (Case III) cause no significant increase in the load carrying capability of the power system. However, for the tidal power plant with high water height conditions, the improvement in the value of IPLCC index is significant.