In the circuit mentioned in CN-0399, ADL5904 and AD7091R is used. ADL5904 is a true rms responding power detector. ADL 5904 gives output in the form of DC voltage.
What is the resolution of this detector ?
Resolution of the circuit dependent on ADC used…
Tengo un kit de evaluacion del ADL5904 desde el año 2014 y de las pruebas que he venido realizando el voltaje de salida siempre fluctua entre 0 y 3,6 voltios aproximadamente , en funcion de los dbm que ingresan. Sin embargo, ahora que reviso las especificaciones…
S-Parameters for the ADL5904's RF input can be downloaded from www.analog.com/adl5904
Hi,
The ADL5904 portable power detector board will be released in the coming months, along with the ADL5904 part also. I am currently in the process of writing the circuit note for this CFTL. After release, you will be able to find the board linked on…
One other thought. If you are just looking to do rms detection at relatively low frequencies, take a look at ADL5904 (www.analog.com/adl5904). It has a linear-in-dB rms output and is lower cost. Frequency range and input power range are similar to ADL5511…
Two related questions:
1. What is the output impedance of the Vrms pin? (I didn't see it in the data sheet but apologies if I just missed it)
2. The data sheet suggests putting a 10nF capacitor on the Vrms pin. What is the function of this capacitor…
ADL5904 has better temperature stability than AD8363 or AD8362. At 30MHz with input power = 10dBm, the threshold variation over temperatures is about 0.2dB.
The data sheet page 8, Table 2. has no value for max current from VRMS pin.
The suggested application has a capacitor directly on this pin, so some source impedance should be there, I would think.
I think I damaged the output by shorting it to ground…
The 0V number in the spec is an extrapolation of the linear region of the transfer function. In practice, at low input levels, the output voltage will go non linear. Some devices will have an offset voltage while the output voltage on others will prematurely…