Insertion Loss in dulpexer

Could someone explain me about Typical and maximum values in Insertion loss parameter ?

I have these 2 values and a graph that indicates the Insertion loss in each frequency.

for example:
http://www.avagotech.com/docs/AV02-1877EN

Insertion Loss in Receive Band (1930.48 ? 1989.52 MHz) In 25 degrees the typical loss is 1.6dB and the max is 3.db.
And when I am looking at the graph - figure 2. Ant?Rx Insertion Loss, I see that the loos in no less the -2.1dB.

Which of them should I take in consideration ?

hi there

The typical values are the ones to consider primarily. BUT as long as you are within the guidelines for operations
that will keep you in that value range. You just need to understand that if you stray from those tolerances then you may end up seeing the max ( worst) values


cheers
Dave

Thanks Dave,

For this specific device for example:
according to the manufacturer (datasheet), What is the IL in the range of 1930.48 – 1989.52 MHz ?
Typical ?
Between typical and Max ?
According to the graph ?

They are saying that at +25C the typical insertion loss is 1.6dB

Read "typical" as their words for...... all things being equal ( take 100 of these devices off the assembly line and the average IL will be 1.6dB) and the circuit that the device is going into is built to specifications then this is the expected insertion loss.
But we appreciate that there are small variations in our manufacturing and so we will give a insertion loss range of our device to cover ourselves and our manufacturing processes.

Thats a rough guide to their thinking, but it will give u the idea :)

Dave

Thanks Dave for your answer.

In the datasheet it says that typ is the average.
Average of all the frequencies in the band ?

Any way, What tool do you use in order to simulate the RF behavior during the electronic path ?

Yes, across the specified freq range and at the specified temperature
but to qualify that a bit, the manufacturer will normally show graphs where they have swept the device with the freq range
and it will show up any peaks and dips in the performance of the device across the freq range


personally none. I'm one of those build and experiment people. If it doesnt work as expected, I will revisit the datasheets etc
and see where I may have gone wrong. One has to remember that the test layout of say a TX power transistor has been achieved after much testing by the manufacturer, so if I follow their board and component layout I shouldnt go to far wrong. :)

Well thats the theory anyway haha

With my Amateur radio activities, my main interests are from VHF to microwaves ( 140MHz to 47GHz) and for some of the higher bands like 10GHz and up I am often modifying commercial equip to operate within the amateur freq allocations. Mainly, particularly above 10GHz there is no amateur equip that can be purchased and modifying commercial gear is the only choice.

cheers
Dave

Thanks Dave.
Cheers :)