RFLW 5N

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Vishay Electro-Films

Revision: 17-Sep-13

4

Document Number: 61087

THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT

TYPICAL COMPONENT PERFORMANCE

Inductance vs. Frequency

Quality Factor vs. Frequency

LAYOUT CONSIDERATIONS

The RF spiral inductor is electrically connected to the circuit by wire bonds. All wire bonds add parasitic inductance and

resistance, as shown in the schematic drawing above.



It is important to note that setup variations might affect the performance of the component. Special care must be given to

minimize these effects by careful design of the component host circuit board. The following aspects should be considered:

• Bond wire length should be minimized. The bond wire added inductance can be roughly estimated at 0.75 nH per mil of

1.25 mil diameter gold wire.

• Any ground plane directly under the component will increase the parasitic shunt capacitance. This will cause self resonance

at lower frequencies.

• The epoxy used to attach the component is the limiting factor in power handling. Applications that require high power handling

are recommended to use high temperature epoxy and to insure adequate heat sinking.

CUSTOM DESIGNED SPIRAL INDUCTORS

Vishay EFI will custom design and measure additional values and form factors upon request.



Typical inductance density is limited to:

It is important to note, that both series resistance and SRF characteristics will degrade as inductance values approach the

inductance density limit presented above.

10

100

1000

10 000

Frequency (MHz)

350

300

250

200

150

100

50

0

18 nH

47 nH

80 nH

52 nH

100 nH

120 nH

150 nH

10

100

1000

10 000

Frequency (MHz)

22

17

12

7

2

- 3

18 nH

47 nH

80 nH

52 nH

100 nH

120 nH

150 nH