One of the biggest challenges integrated passive device (IPD) manufacturers still face is trying to sell the IPD concept of looking at total installed cost, not just cost of the part, when compared with discrete solutions. Despite this challenge, there are many new IPD and passive-array products that are well-suited to high-reliability designs in which higher performance, coupled with a need to save space, are top priorities.
With this in mind, several passive-component suppliers have developed interesting IPD and array products.
Vishay Intertechnology (Malvern, Pa.) has developed a surface-mount multilayer ceramic chip capacitor with an integrated resistor for controlled-discharge applications. Appropriately dubbed the controlled discharge capacitor (CDC), this IPD targets circuits that use a bleed resistor to discharge a capacitor faster, typically for safety reasons.
|HIGH-PERFORMANCE SPACE-SAVERS: Novacap's Cap-Rack component arrays offer mix-and-match capacitance values and dielectrics, along with integrated resistors and inductors; Vishay's controlled discharge capacitor includes an integrated resistor.
By integrating the resistor with the capacitor, the CDC improves the performance of this type of circuit because it discharges very fast and improves reliability, said David Valletta, executive vice president of worldwide sales for Vishay.
Preliminary electrical specs include a capacitance value of 0.18 µF, voltage rating of 1,000 Vdc to 1,500 Vdc, and resistor value of 500 ±30 Mohms. The operating temperature range is -55 º C to +125 º C. Dissipation factor is 2.5 percent maximum at 1.0 Vrms and 1 kHz. The temperature coefficient of capacitance (TCC) is ±15 percent from -55 º C to +125 º C with 0 Vdc applied (X7R dielectric).
The technology was developed for military applications and can be used in detonation devices, downhole drilling, construction and mining applications.
Specialty component manufacturer Novacap (Valencia, Calif.) launched its Cap-Rack (CR) series of component arrays earlier this year, integrating a custom selection of individual ceramic components in a single surface-mount package. These components can consist of highly matched multilayer ceramic capacitors (MLCCs) and/or a combination of MLCCs with dissimilar capacitance values and dielectrics (NPO, X7R, Y5V). They also can be configured to include other passive devices, such as ceramic resistors and inductors.
Initially targeted at medical implantable devices, these are smaller, very reliable capacitors in terms of design, materials and process, said Scott Sentz, Novacap director of marketing. Medical device designers were looking for space savings and a reduced cycle time by placing one device instead of putting down four to six components, he explained.