RF System in Package Design for Portability Between Suppliers and Technology Platforms

摘要

Today, the System-in-Package approach offers a new dimension to system integration, far beyond mere dense micro-packaging of existing System on Chip solutions. Not only does SiP offer the capability to integrate almost any kind of companion passive component with a given active circuit, but it also enables flexible combinations of analogue circuits and RF functions with digital integrated circuits. The SiP approach is a key driver for the miniaturization trend for portable devices (Cell-phones, PDAs, Ultra-miniature PCs), particularly with respect to the growing number of RF functions that need to be integrated. Most SiP design methodologies, that include integrated passive components, rely on fixed libraries of components that are locked to a particular substrate supplier and stack-up. For high volume consumer devices it is increasingly important to ensure that any given SiP can be sourced from at least two independent manufacturers. The novel design methodology that is presented in this paper is aimed at allowing easy transfer of integrated passive circuit design from one supplier to another and even from one technology to another (e.g. LTCC to IPD). The methodology is based on a user extendable library of mechanical objects for which the electrical models are created automatically for a given stack-up and/or technology. Thus any design that is initially made for a particular supplier can easily be re-tuned for an alternative source. The second manufacturer can have a completely separate set of electro-mechanical parameters (stack-up, dielectric constant, layer thickness, loss factors, metal types) and may even use an alternative technology. The paper will illustrate the design method with some examples of RF SiP designs that have been ported between LTCC suppliers and between LTCC and IPD technologies.