AD604
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The AD604 is an ultralow noise, very accurate, dual-channel, linear-in-dB variable gain amplifier (VGA) optimized for time-based variable gain control...
Datasheet
AD604 on Analog.com
Hi
I am using AD604 in my project, i am not sure how this is working,
G (20 dB/V) = 20 × VGN – 5, VREF = 2.500 V
Vref input is 2.5V, VGN is 0.5volt with this input,
I am not getting gain as per the above formula, instead i am getting 0db gain for the first channel instead of 15db gain.
It is having R-1.5R ladder network with 7 tap, Using preamplifier gain as 14db by connecting FB pin to Output pin of preamplifier 1 stage and fixed 34.4db of gain at the output, this itself gives 48.4db of gain, what is the use of ladder network attenuator gain of 48db.
please let us know how it works and what is the use of using this amplifier in the RF front end.
Thanks
