ADL5385 allowed baseband input signal range?

Question Which is the allowed input range for the baseband inputs of ADL5385?? Answer Under 2Vpp (1Vpp at each input) baseband amplitude operation is highly recommended to meet the absolute maximum ratings. Each input has to be biased with 500mV. The dc common-mode bias level for the baseband inputs can range from 400 mV to 600 mV. This results in a reduction in the usable input ac swing range. The nominal dc bias of 500 mV allows for the largest ac swing, limited on the bottom end by the ADL5385 input range and on the top end by the output compliance range on most Analog Devices DACs. By the way, the absolute maximum range of the basband inputs IBBP, IBBN, QBBP, QBBN is 0V to 2V.

What is the low frequency operating limit for ADL5385 and ADL5386?

Q. What is the low frequency operating limit for ADL5385 and ADL5386? ------------------------------------------------------------------------------------------------------------ A. The ADL5385 and ADL5386 are specified to work down to output frequencies of 50 MHz. In practice you can operate them at slightly lower frequencies. There are however two constraints. Firstly, the output of the IQ Modulator is ac-coupled. This results in a 3 dB high-pass corner frequency of approximately 10 MHz (see attached plot). In practice, you should not operate close to this frequency as it will result in phase and amplitude distortion of the output signal. Operation at a minimum frequency of around 30 MHz is more realistic. In addition to this constraint, the gain of the LO input path decreases with decreasing frequency. Below, the level shown in the attached plot, the IQ modulator core will not operate (you will see a massive rise in the noise floor). So for good operation down to 30 MHz, an LO power level that is well above this is recommended (an LO power level of 0 dBm was found to work well). Author's Note (May 3rd, 2013): Since this original posting was made, the datasheet for ADL5385 has been updated and now includes specs at 30 MHz and a minimum specified operating frequency that has been reduced from 50 MHz to 30 MHz with the proviso that a mimumum LO power level of 0 dBm should be used.