Dear all, I need to design a 4.4-5.GHz power detector for direct and reflected power ( so i need 2 power detector) with a dynamic range of 55dB a temperature range of -35 to 90°C and i have just 150mA to bias them. I selected the ADL5519 and AD8318, but which is the best choice according to you?Best regardsStefano Casilli RF Power Amplifier Designer
AD8318 does not fully cover the top end of your specified operating temp range. We cannot recommend it for your application.
ADL5519 may work. Current consumption 60mA is OK. You might want to look at datasheet figures 27 and 29 to see if the range and accuracy looks acceptable.
I'm sorry, i meant AD8318EP. It should work
Either of those parts should work OK. The ADL5519 dual detector may be preferable because of smaller overall solution size and lower current. AD8318-EP looks preferable for accuracy at hot. Note that if AD8318-EP DC current consumption is near the max specified value of 82mA, 82 x 2 = 164mA would exceed your 150mA budget.
Also consider any modulation that might be present. The log detectors provide good accuracy for CW and pulsed CW waveforms, while RMS responding detectors will be best accuracy if complex modulation is present.
Also remember that there is always part-to-part variation of log slope and intercept. For best accuracy, we recommend that the system design include a provision for individual in-system calibration of the detector.