About LTCC

Can anyone discuss LTCC used in RF front end?Maybe I could do it in coming future.
From some webs, I find that it is mainly used in passive elements,especially filters and vco...

Anyone advices?

Hi,
LTCC is one of the low cost MCM technologies, you can find good info about this in the following website www.valtronic.com.
regards,

- long delivery time
- not for high power design (bad heat conducting)

They are very good for making modules that use transmission lines like filters and couplers. I saw one that was multilayered and had about six filters in a square cm or two.

LTCC is a good approach for a front end when cost and/or complexity are driving the design. It has decent thermal charateristics, although electrically, due to the roughness of the metalization, the losses can be a little higher than soft substrate.

Reasons to use LTCC:
- Extremely complex multilayer circuits (30+ Layers) including over 80,000 vias (blind, if necessary) per layer

- Touch labor is low compared to similar circuits in other substrates

- Very good precision

Reasons not to use LTCC:

- Vendor stability. The vendor's firing profiles vary to the point that you design to their process

- Shrinkage. While in local precision is excellent, a large scale shrinkage is rather unpredictable. Flatness is also an issue