As sensitive inline RF performance influences new designs, designers are scrutinizing components quite differently. One popular technique being utilized by designers is “planarizing” the components so they align in the same plane as the transmission line in RF applications. Keeping the resistor and the transmission line in the same plane reduce losses and minimizes the effects of capacitance. At DC, the resistor is simply governed by ohms law. However in an RF environment, certain parasitic effects and contributions must be accounted for. The same resistor that performs termination functions adequately at DC or low frequencies can often exhibit different performance at higher frequencies due to unwanted capacitance and inductance present when utilizing various package designs. When using a wraparound, (WA) termination, the resistor forms a small series inductance and the chip terminals form a small shunt capacitance. As frequency increases the capacitance value eventually becomes dominant and must be managed. The partial wrap, PW resistors are designed to be mounted face down and therefore have better parasitic performance than the WA style under similar layout and operating conditions. The terminals are partially wrapped around the side of the chip so when they are mounted face down, the solder joint can [...]

Introduction Contemporary electronic board designs are becoming more challenging to designers than ever before. In today’s thick film, component applications designers are often faced with a trade-off between process flexibility and component performance. In terms of magnetic sensitive applications, this often requires the use of components that are sensitive to processing or attachment methods and therefore limit options for installation. At times this restricts the use of certain solders, temperatures or multiple re-flow operations. In applications where extreme processing is used with vulnerable components, failure modes can include component detachment or intermittent loss of continuity due to metal leaching of contacts and terminals. In order to understand this challenge and its factors, it is helpful to list the perfect performance characteristics of a thick film component. 1) Withstands high heat 2) Resists high Sn content solder 3) Non-magnetic 4) RoHS compliance 5) Affordability 6) Value diversity In designs where magnetism and RoHS compliance are in demand (i.e. medical imaging) resistance to high temperature solder and “non-magnetic” properties are critical. Unfortunately, they oppose each other from a process perspective. Traditionally, highheat RoHS compliant applications could often be addressed with nickel-barrier parts. These parts are readily available and very durable due to [...]

A ThermaBridge™ is a specialty thick film component developed and offered by IMS for use in the thermal management of electronic devices and modules. These products operate under the simple principle of conducting as much heat energy as possible, while simultaneously serving as an outstanding insulator of electrical energy and signal. The combination of these characteristics makes the ThermaBridge™ a very useful and flexible component that designers use to move heat either in, out, or to balance the temperature between two locations. ThermaBridges™ accomplish this without any fans, power, or moving parts making them useful for every electrical design sensitive to the effects of thermal energy. ThermaBridges™ operate by providing an electrically isolated, thermally active link between high heat generating areas and low temperature heat sinks or other locations within a circuit. According to Fourier, maximizing heat flow from one high temperature area to a lower one is made efficient by limiting the distance between the two points, maximizing the area of the conductive path and optimizing the material’s conductive heat properties. ThermaBridges™ do this by using Aluminum Nitride ceramic and offering a variety of thicknesses, lengths and widths to suit any thermal/mechanical requirement. For example if we take the [...]