Vertically-stacked capacitor assemblies help reduce PCB footprint

Knowles Precision Devices, a division of Knowles Corporation, has expanded its capacitor assembly offering with the new SV series of capacitor assemblies for power supply filtering applications. Suited for the input and output stages of switch mode power supplies and DC/DC converters, these vertically-stacked ceramic capacitor assemblies help to reduce the overall circuit board footprint.

“Capacitor assemblies have the advantage of minimizing board space for a given capacitance,” said Dan Callen, product manager, Knowles Precision Devices. “Also, as the assemblies are separate individual capacitors, they have increased overall surface area which helps reduce mechanical and thermal stress.”

The assemblies can incorporate up to 10 chips of the same size with various lead configurations to safeguard against thermal and mechanical stresses, he added. “The SV series is 100% tested for dielectric withstanding voltage, insulation resistance, capacitance, and dissipation factor.”

The capacitor assemblies are built on the company’s Cap-Rack technology that bonds chips of the same size using a high-temperature epoxy, resulting in high capacitance in a small footprint.

The SV series capacitor assemblies are available in the X7R dielectric with a high capacitance-to-volume ratio. Low equivalent series resistance (ESR) and low equivalent series inductance (ESL) are inherent in the SV series design, according to Knowles, which gives the assemblies the capability to handle high ripple currents at high frequencies.

The low ESR helps reduce power loss and improve reliability particularly at high ripple currents, which can cause self-heating losses and degradation in a capacitor, said Knowles.