Spotlight on Passives

Apr 1, 2008 12:00 PM

Multilayer Capacitors

The EVC series of multi-layer monolithic ceramic capacitors (MLCCs) from Murata Electronics features higher ripple-current capabilities, high voltage and large capacitance per volume, lower ESR and ESL compared to film and aluminum electrolytic capacitors (better surge suppression), and high operating temperature assurance.

For example, the maximum-rated capacitor in this series has a voltage rating of 630 Vdc and an effective capacitance of 12 µF at 400 Vdc. The allowable ripple current is 20 Arms at 20 kHz, with a dielectric withstanding voltage of 750 V and maximum operating temperature of 125°C. The case size is 32 mm × 40 mm × 3.7 mm for capacitors with 250-Vdc, 400-Vdc and 630-Vdc ratings or 16 mm × 20 mm × 3.7 mm for a 35-Vdc rated MLCC.
Murata Electronics
Kyoto, Japan
www.murata.com

Ultra-Thin Supercapacitors

Tecate Industries' CAP-XX ultra-thin G Series of general-purpose supercapacitors consists of single-cell and dual-cell versions. The RoHS-compliant parts boast low impedance and a very low profile. The supercapacitors offer long-life performance at up to 2.3 V in the single-cell versions and 4.5 V in the dual-cell configurations, with two cells connected in series.

The GW Series features a 28.5-mm × 17-mm footprint and combines high capacitance (up to 0.4 F at 4.5 V) with ESR as low as 60 mµ in a thin (0.9-mm to 2.9-mm) package. The GS Series features a 39-mm × 17-mm footprint and combines high capacitance (up to 0.7 F at 4.5 V) with ESR as low as 34 mV in the same thin package. Pricing starts at $3.06 each in quantities of 1000.
Tecate Industries
San Diego
www.tecategroup.com

400-F Supercapacitors

A supercapacitor from Illinois Capacitor provides 400 F at 2.7 V in a 25-mm × 62-mm package. The 407DCN2R7K has an equivalent series resistance of 3 mµ at 120 Hz with a load life of 87,600 hr at 25°C with 100% of rated voltage.
Illinois Capacitor
Lincolnwood, Ill.
www.illinoiscapacitor.com

Polymer Capacitors

Nichicon's F11 series of capacitors uses layered-aluminum construction, conductive polymer electrolyte and a three-terminal design all in a molded package. This structure decreases the magnetic field and inductance at ultrahigh frequency, so the part achieves excellent impedance characteristics over a wide frequency range. The layered-aluminum design of the F11 series provides the ultralow ESR and ESL over a wide frequency range needed in today's high-performance LSI.

With a voltage range of 2.5 V to 6.3 V and a capacitance range of 47 µF to 2400 µF, the F11 series' operating temperature range is -55°C to 105°C. The capacitors come in two sizes: 16.7 mm × 12.1 mm × 2.5 mm and 8.5 mm × 5.3 mm × 2 mm. Both sample and production quantities are available.
Nichicon
Schaumburg, Ill.
www.nichicon.com

HID Lighting Capacitors

Cornell Dubilier's series of HID lighting capacitors are rated for 60,000 hr life at 100°C. The Type DL capacitors' catalogued capacitance values range from 5 µF to 75 µF with a voltage range from 120 Vac to 400 Vac.

The Type DL capacitors are packaged in cylindrical plastic cases ranging from 30 mm to 50 mm in diameter and 55 mm to 117 mm in length. Pricing starts at $1 each.
Cornell Dubilier
New Bedford, Mass.
www.cde.com