As the electronics content in the automotive industry continues on its steady upward climb, passive component manufacturers are responding to the industry's need for higher performing capacitors, inductors and resistors with the roll out of several new product developments over the past year.
By using any combination of new processes, materials or technologies, component manufacturers such as AVX, EPCOS, IRC, Perllo, Stackpole, Vishay and Welwyn have addressed several key component concerns in the auto industry including thermal issues and reliability. They are also making big strides in the development of lead-free components.
When it comes to automotive applications, cooler operation is a top priority. TT electronics IRC Wirewound and Film Technologies Division, for example, said its new OAR and OARS series of precision current sense resistors offer high dissipation and cooler operation for automotive subsystems. Both lines feature a unique form factor of the copper leads that keeps the resistors "hot spot" off the PC-board for better air circulation around the devices. (Search www.eeProductCenter.com for article ID: 18401066)
The company also notes that although the OARS series resistors are only rated for 1W at 85°C, automotive customers have successfully increased the device's heat dissipation to as high as 4 watts by using high temperature solder, ceramic or metal substrates or extra copper on the PC-board landing pads. They are also capable of handling surge currents higher than conventional resistors.
Similarly, Stackpole Electronics said its new BR series of open air current sense resistors for motor control and power regulation applications features a resistive element with a unique off the board design that keeps the resistor's "hot spot" off the PC-board and allows air to circulate around it, contributing to cooler operation. (Search www.eeproductcenter for article ID: 159402971)
Stackpole's BR series current sense resistors
Responding to thermal performance concerns, AVX Corp. has developed a unique soft termination layer system (Search www.eeproductcenter for article IDs: 18400642 and 60407841) for its multilayer ceramic chip capacitors (MLCCs) that improves temperature cycling performance and reduces failures associated with mechanical board flexure, which makes these devices more than suitable for use in harsh automotive applications particularly in the engine compartment.
AVX's FlexiTerm soft termination system
Also developed for harsh automotive environments, TT electronics' Welwyn Components Division claims it has developed the highest power surface-mount resistor that can handle these severe conditions. (Search www.eeproductcenter for article ID: 18402631). The WA80Z series also resolves thermal management problems, and will fuse safely under fault conditions. Similar to IRC and Stackpole designs, this device incorporates a lead configuration design that raises the resistor off the PC-board for better heat dissipation.
Withstanding high vibration is another critical area for auto applications, EPCOS's B41605 and B41607 aluminum electrolytic capacitors feature high vibrational strength and maximum ripple current capability at high temperatures and frequencies. The company attributes these characteristics to its special corrugated design which has passed all vibration tests up to 30 g and 2 kHz, even after prolonged thermal stress over 2,000 hours at 125°C. (Search www.eeproductcenter for article ID: 49900372)
In critical safety applications, TT electronics IRC Wirewound and Film Technologies Division has designed a new series of rugged surge resistors to manage overloads in motor control circuits for automotive and industrial applications. The HSF resistors also provide excellent heat dissipation and a higher surge/pulse capability with its cylindrical design. They can be used in harsh environments where heat and vibration are trouble spots. (Search www.eeproductcenter for article ID: 29100187)
IRC's HSF surge resistors
Passive component manufacturers are also focused on complying with the European Union's Restriction of Hazardous Substances (RoHS) directive. In addition to its lead-free status, the new Vishay Beyschlag ACAC 0612 precision series and ACAC 0612 professional series resistor arrays are designed for applications that demand high component densities and stable resistor performance. (Search www.eeproductcenter for article ID: 60402608)
For inductors, Vishay offers a new IHLP inductor with a 100% lead-free construction. These tough devices are also resistant to moisture, salt, and chemicals, which make the new low-profile, high-current IHLP inductor suitable for automotive applications and other extreme environments. In addition, a molded construction gives IHLP devices a higher dielectric withstanding voltage that allows for enhanced protection against electrical shock, and the flame-retardant encapsulant provides resistance to corrosion and moisture. (Search www.eeproductcenter for article ID: 56200537)
Similarly, Perllo Technologies LLC and manufacturing partner ECM Electronics Ltd. have introduced a new ECxxC series of lead-free power inductors for automotive and industrial control applications. These devices tout better reflow solderability and higher current handling capability. (Search www.eeproductcenter for article ID: 60403491)