If an output of an ic is given 14dBm and it's gain is 13dB. So if an input of 12dBm is applied then what must be it's output ?

 

If an output of an ic is given 14dBm and it's gain is 13dB. So if an input of 12dBm is applied then what must be it's output ?

It doesn't work that way. Using dBm means that you have a FIXED reference of 1 milliwatt. If the input was 12 dBm the device would probably be overloaded. The 14 dBm output is obtained with an input of 1 dBm. So 1 dBm plus a gain of 13 dB gets you 14 dBm. Got it?

 

Hello,

When you want to drive an amplifier capable of 14 dBm output and a gain of 13 dB with 12 dBm input, you will likely blowup the amplifier.
If it not gets blowup, a lot of unwanted signal will be present on the output due to the non linearity of the amplifier.

Bertus

 

It doesn't work that way. Using dBm means that you have a FIXED reference of 1 milliwatt. If the input was 12 dBm the device would probably be overloaded. The 14 dBm output is obtained with an input of 1 dBm. So 1 dBm plus a gain of 13 dB gets you 14 dBm. Got it?

Okay thank you.

 

Hello,

When you want to drive an amplifier capable of 14 dBm output and a gain of 13 dB with 12 dBm input, you will likely blowup the amplifier.
If it not gets blowup, a lot of unwanted signal will be present on the output due to the non linearity of the amplifier.

Bertus

A bit dramatic perhaps. Many amplifiers have overload protection, but your point is well taken

 

It doesn't work that way. Using dBm means that you have a FIXED reference of 1 milliwatt. If the input was 12 dBm the device would probably be overloaded. The 14 dBm output is obtained with an input of 1 dBm. So 1 dBm plus a gain of 13 dB gets you 14 dBm. Got it?

I am using hmc462lp5 which is an lna . In its data sheet the output power is given 14.5 dBm, 13dB gain and absolute maximum rating of input power which is 18dBm. With these values won't the ic get overloaded ?

 

Hello,

Did you see the specs table?



With 12 dBm input and 13 dB gain you will get vey close to the IP3 point and go over the saturation point.

Bertus

 

Hello,

Did you see the specs table?

View attachment 127671

With 12 dBm input and 13 dB gain you will get vey close to the IP3 point and go over the saturation point.

Bertus

So why they have given absolute maximum rating of input power 18dBm ? Won't it gon way over the saturation point ?

 

So why they have given absolute maximum rating of input power 18dBm ? Won't it gon way over the saturation point ?

18dBm on the input is probably where destruction begins.

 

18dBm on the input is probably where destruction begins.

I see. Thank you