Ferrite Pot Cores
What are Ferrite Pot Cores?
he pot core shape provides a convenient means of adjusting the ferrite structure to meet the specific requirements of the inductor. Magnetics® classifies the following cores as a pot core type; PQ, Pot Cores, RS, DS, RM and EP. Hardware is available for most sizes. Because of their design and composition, pot cores offer a number of advantages, including: self-shielding, space efficiency, convenience, good temperature stability, low losses, and high Q. Typical applications for pot cores include power transformers, power inductors, converter and inverter transformers, switched-mode power supplies and filter inductors.
For more technical information including: material properties, core losses, and a comparison with other materials view the official Magnetics Ferrite Core Catalog
PQ Cores
PQ cores are designed specifically for switched-mode power supplies. This design provides an optimized ratio of volume to winding area and surface area. As a result, both maximum inductance and winding area are possible with a minimum core size. The cores provide maximum power output with minimum assembled transformer weight and volume, in addition, to taking up a minimum amount of area on the printed circuit board. This efficient design provides a more uniform cross-sectional area; thus cores tend to operate with fewer hot spots than with other designs. Typical applications include power transformers and power inductors.
Industry standard PQ core sizes include: PQ20/16, PQ20/20, PQ26/20, PQ26/25, PQ32/20, PQ32/30, PQ35/35, PQ40/40, PQ50/50
Pot Cores
The pot core shape is a convenient means of adjusting the ferrite structure to meet the specific requirements of an application. Both high circuit Q and good temperature stability of inductance can be obtained with these cores. Pot cores, when assembled, nearly surround the wound bobbin. This self-shielded geometry isolates the winding from stray magnetic fields or effects from other surrounding circuit elements. Typical applications for pot cores include; differential inductors, power transformers, power inductors, converter and inverter transformers, filters, both broadband and narrow transformers and telecom inductors.
Industry standard pot core sizes include: P9/5, P11/07, P14/08, P18/11, P22/13, P26/16, P30/19, P36/22, P42/29
RS-DS Cores
Slab cores are modified pot cores with the sides removed. The slabs can be paired with one round half of a standard pot core (RS combination) or two slabs can be paired together for a double slab (DS combination). The RS geometry offers all the advantages of pot cores for filter applications, plus many additional features for power applications. DS cores accommodate large size wire and assist in removing heat from the assembly. Typical applications for RS-DS combinations include; low and medium power transformers, switched-mode power supplies, and converter and inverter transformers.
Industry standard RS-DS core sizes include: 14/08, 18/11, 23/11, 23/18, 26/16, 30/19, 36/22, 42/29
RM Cores
RM cores are square-designed cores that offer all the magnetic and mechanical advantages of pot cores, plus the added feature of maximizing magnetic performance while minimizing PC board space. Easy to assemble and adaptable to automation, completed units provide at least 40% savings in mounting area compared to a similar size pot core assembly. Typical applications include differential inductors, power inductors, filter inductors, telecom inductors and broadband transformers.
Industry standard RM core sizes include: RM4, RM5, RM6, RM7, RM8, RM10, RM12, RM14
EP Cores
EP cores are round center-post cubical shapes which enclose the coil completely except for the printed circuit board terminals. This particular shape minimizes the effect of air gaps formed at mating surfaces in the magnetic path and provides a larger volume ratio to total space used. EP cores provide excellent shielding. Typical applications for EP cores include differential and telecom inductors and power transformers.
Industry standard EP core sizes include: EP7, EP10, EP13, EP17, EP20