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Design >> RF Design >> Transceiver Design (Inductors)
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Message started by vicm6799 on Oct 12^th, 2015, 10:12am

Title: Transceiver Design (Inductors)
Post by vicm6799 on Oct 12^th, 2015, 10:12am

Hello. Could any of you RF engineers be able say if a die contains inductors (octogonal shaped structures) located on the top most layer of a die would this automatically imply that the IC has RF capabilities ? Another words that the IC could be considered a transceiver or a transmitter device ? Could inductors found on the top most layer of the die indicate anything else other then containing RF properties ?

Thanks

Title: Re: Transceiver Design (Inductors)
Post by loose-electron on Oct 14^th, 2015, 9:54am

Generally the presence of inductors within an IC indicates an RF front end circuit of some form.

Inductors take up a lot of space and except for RF circuits, designers have generally been able to avoid putting them inside an IC.

Title: Re: Transceiver Design (Inductors)
Post by vicm6799 on Oct 19^th, 2015, 7:47pm

loose-electron wrote on Oct 14^th, 2015, 9:54am:

Thanks loose-electron. Would you be able to share that once a De-cap is done to expose the die (top layer) what further examination could be done to confirm and verify that the inductors are in fact representing a transceiver or transmitter design ? Would the presence of these inductors also represent receiver (receive but not send out) technology ? Would locating amplifiers, modulation circuits, oscillator etc on the top layer also facilitate the presence of a transceiver or transmitter ?

Thanks very much

Title: Re: Transceiver Design (Inductors)
Post by sheldon on Oct 20^th, 2015, 9:52pm

The presence of inductors could also indicate the presence of an LC
oscillator for a PLL. This does not have to be for Rf applications,
they are also used in high speed I/O applications.

Title: Re: Transceiver Design (Inductors)
Post by vicm6799 on Oct 20^th, 2015, 11:11pm

sheldon wrote on Oct 20^th, 2015, 9:52pm:

The presence of inductors could also indicate the presence of an LC
oscillator for a PLL. This does not have to be for Rf applications,
they are also used in high speed I/O applications.

Hello and thank you. Could please explain in layman's terms what exactly what is a PLL technology ? The basis of the question was to address the circuit design of Northbridge logic core IC found on desktop and laptop motherboards. However the question could also apply to MCU's which have no RF capabilities such as an older model DVD player. Having said the above would you still find these inductors on the top most layer of either the NB logic core die or on a MCU both with no disclosed RF capabilities ?

Thanks for the response.