Snap-in Aluminum Capacitors Enable Higher Power Density


Miniature Devices Offer Increased Ripple Current to 5.05 A and Useful Life of 5,000 Hours at 85 °C

Vishay Intertechnology, Inc. introduced a new series of miniature snap-in power aluminum electrolytic capacitors that enables higher power density designs. The Vishay BCcomponents 257 PRM-SI series offers up to 20 % higher ripple current than previous-generation solutions in case sizes that are up to 20 % smaller while providing longer useful life to 5,000 hours at 85 °C.

With ripple currents up to 5.05 A, the devices released today allow designers to utilize fewer components to save board space and lower costs. Featuring a cylindrical aluminum case, insulated with a blue sleeve, 257 PRM-SI series capacitors feature rated voltages to 500 V in 25 compact case sizes ranging from 22 mm by 25 mm to 35 mm by 60 mm. The RoHS-compliant devices are also available with 3-pin keyed polarity snap-in terminals.

As polarized aluminum electrolytic capacitors with a non-solid electrolyte, the devices are ideally suited for smoothing, buffering, and DC-Link filtering in switch mode power supplies used in medical, consumer welding, and test and measurement equipment, in addition to general industrial control and audio / video system applications.

Device Specification Table:

Case size (D x L in mm)

22 x 25 to 35 x 60

Capacitance range

56 µF to 3300 µF


± 20 %

Rated voltage

200 V to 450 V

500 V

Category temperature range

-40 °C to +85 °C

-25 °C to +85 °C

Useful life at +85 °C

5,000 h

Max. ESR at 100 Hz

70 mΩ to 3740 mΩ

Max. impedance at 10 kHz

60 mΩ to 3240 mΩ

Sectional specification

IEC 60384-4 / EN130300

Climatic category IEC 60038

40 / 85 / 56

25 / 85 / 56

Samples and production quantities of the 257 PRM-SI series capacitors are available now, with lead times of 14 weeks. Pricing depends on capacitance and voltage rating. For example, the price for 1200 µF / 250 V devices in the 30 mm by 45 mm case size is $3.34 per piece in 2,000-piece quantities.

Vishay can be found on the Internet at