dimension of inductors used on chip

[raghavg02]

Hello,

I am designing a dc-dc step down converter. I was wondering if anybody could guide me about the actual dimension of the inductors usually employed for this purpose? I have come to know that the inductance values used for step-down converters ranges between 1 to 100 uH. Thanks in advance !

 

[FvM]

inductance values used for step-down converters ranges between 1 to 100 uH

I doubt that the inductance range is available for on-chip implementation. What are your design objectives?

 

[raghavg02]

I doubt that the inductance range is available for on-chip implementation. What are your design objectives?

Well I am going to design a simple step down dc-dc converter and then will be testing its performance by using a 'hybrid inductor' fabricated by another research group. So, this experiment to actually test the effect of this 'hybrid inductor'. I found somewhere on the net that for step down dc-dc converters inductance values that are used is between 1-100uH. So, by choosing say 20uH, how can I come to know about its on-chip dimension ? It is necessary to know the on chip dimension because then accordingly the other group will make the 'hybrid inductor'.

 

[FvM]

In usual terms, "on-chip" refers to IC design and dimensions of e.g. several 100 µm. If you refer to hybrid circuits, larger inductors might come into sight. But there's also a problem of conductor resistances and magnetical stray fields. At the end of the day, discrete inductors with ferrite core might give considerable better performance. As far I'm aware of, this is also the way how converter modules e.g. from Linear are made.