Capacitors, one of the unsung workhorses of the electronics industry, continue to broaden their capabilities. High-capacity versions are beginning to push battery technologies in some applications, providing quick bursts of power, while passives designed for military applications help trim costs and shorten development times.
In more conventional markets, versatile capacitors are constantly improving performance despite the constant pressure to save space. “The industry continues to make parts smaller yet we’re getting more power and functionality from them,” says David Valletta, senior vice president for Vishay Worldwide Strategic Sales.
Ultracapacitors fit C-cell format, reducing weight
Maxwell Technologies Inc.’s Boostcap 2.5V ultracapacitor cells and multi-cell packs have the same external dimensions as the familiar C-size battery but weigh only one-third as much.
The 120-farad BCAP0120 P250 Power-type C-cell is engineered for high-cycling applications that require the lowest equivalent series resistance (ESR) and highest efficiency, while the 140-farad BCAP0140 E250 Energy version is designed to provide more economical solutions for lighter duty applications. Both lines can be packaged in a six-cell, 15-V pack.
The ultracapacitors are hermetically sealed with a double seaming process to ensure long life and reliability. Applications include industrial robotics, actuators, telecommunications back-up, aircraft door and air bag actuation, and distributed power nodes for automotive subsystems.
Tantalum capacitors meet military requirements
Solid tantalum chip capacitors from Vishay Intertechnology Inc. provide high-reliability screening and surge current testing options. The Tantamount ®Hi-Rel COTS T95 series, designed for safety-critical avionics and military applications, offer designers ratings not currently available MIL specifications.
These conformal-coated capacitors have a capacitance range of 0.1 ́F to 680 ́F and a voltage range from 4V to 50V. They offer low ESR values that extend down to 0.055 Ù at 25C and 100 kHz. T95 devices series operate over a temperature range of –55 to 125C.
The surface-mount capacitors, which can be tested to the MIL-PRF-55365 specification, come in standard EIA tape-and-reel packages and feature standard SnPb terminations, with 100 percent tin terminations available. Pricing varies with values.
Compact RF capacitor line extends performance
RF capacitors from AVX Corp. extend their capabilities, offering the lowest ESR available in a 0805 package size. The SQCF line is designed for RF amplifier applications, as well as base stations, wireless infrastructures and point-to-point, multipoint radio applications.
Along with low ESR, the line has high series resonance, and high stability when voltages, frequency and temperature change. The EIA 0805 case size packages are RoHS compliant with 100 percent Tin terminations. Tin/Lead terminations are available for military and other exempt applications.
The SQ Series also comes in 0603, 0605 and 1210 case sizes. Operating voltages range up to 250V dc with capacitance of 240 pF. Pricing starts at $.092 for 10,000 pieces. Smaller 500 piece reels are available for prototypes.