FET operating conditions "Input Power MAX 0dBm". Can't understand its meaning.

[Terminator3]

FET operating conditions "Input Power MAX 0dBm". Can't understand its meaning.

I do not understand what does it mean. For example, some design use such transitors to provide amplify LO up to few dBm in. And frequency multipliers, where input already above 0dBm, maybe 5dBm or so. Does it mean that transistor is used above it recommended operating conditions?

 

[FvM]

Re: FET operating conditions "Input Power MAX 0dBm". Can't understand its meaning.

We can't know without seeing the document.

 

[Terminator3]

Re: FET operating conditions "Input Power MAX 0dBm". Can't understand its meaning.

For exmaple this one www.cel.com/pdf/datasheets/ne3210s1.pdf

RECOMMENDED
OPERATING CONDITIONS (TA = 25°C)
PART NUMBER NE3210S01
SYMBOLS PARAMETERS UNITS MIN TYP MAX
VDS Drain to Source Voltage V 2 3
IDS Drain Current mA 10 15
PIN Input Power dBm 0

But here **broken link removed**
i can't see any Pin data.

 

[FvM]

Re: FET operating conditions "Input Power MAX 0dBm". Can't understand its meaning.

Obviously the transistor is designed for linear gain stages, not frequency multipliers or class B, C ... output stages.

You may use it for other applications, if you don't have a better suited device at hand and keep the maximum ratings, particularly Vds and Vgs.

 

[crutschow]

Re: FET operating conditions "Input Power MAX 0dBm". Can't understand its meaning.

dBm is just the power in Decibels relative to 1mW. For example, 0dBm is 1mW and 5dBm is 1.78mW.

 

[FvM]

Re: FET operating conditions "Input Power MAX 0dBm". Can't understand its meaning.

dBm is just the power in Decibels relative to 1mW

I'm under the impression, the OP knows about dBm.

 

[dick_freebird]

Re: FET operating conditions "Input Power MAX 0dBm". Can't understand its meaning.

This low an input power level probably means that it's about
linearity specs or something like that; the 50-ohm voltage
is too low to be intrinsically damaging (225mV RMS, crest of
about 0.315V) especially in a high-bandgap device like the
NE3210. But in that datssheet, 0dBm is the recommended
operating input level, not a limit value - more like, the basis
of datasheet parametric specs like gain, NF, linearity and so
on.

Your other device, evidently the vendor does not feel the
need to assert a recommended condition. More likely the
input power will be a secondary determination based on
something like (say) output power at compression divided
by worst case power gain.