we are confused about input / output common voltage & input / output range !
Please let me know, which is correct.
In the datasheet, following is it.
INPUT/OUTPUT CHARACTERISTICSInput Common-Mode Voltage Adjustment Range 1.2 to 3.8 V typMax Output Voltage Swing 1 dB compressed 4.75 V p-p typ
Pin Function Descriptions
INHI Balanced Differential Input. Biased to midsupply, typically ac-coupled.INLO Balanced Differential Input. Biased to midsupply, typically ac-coupled.
VOCM Voltage applied to this pin sets the common-mode voltage at both the input and output. Typically decoupled to ground with a 0.1 μF capacitor.
The common-mode output voltage level can be adjusted from 1.2 V to 3.8 V by driving thedesired voltage level into the VOCM pin
What is input common voltage range?
What is input range & AMR about input pin ?
What is output common voltage range?
What is true function about Vocom pin ?
Can you provide the example of a single-ended-to-differential, dc-coupled, INHI input circuits w/ AD8351 ?
I'm not an expert on AD8351 but I'll try to respond to your questions:
Response: AD8351 is essentially meant to be operated AC-coupled. The inputs (INHI and INLO) are self-biased to mid-rail. As far as VOCM is concerned, the 1.2V to 3.8V range applies.
The absolute maximum ratings for the input(s) is not specified. It is common to limit these voltages to less than one diode drop (about 0.25V over temperature) above VPOS and to below GND.
Response: With VCOM set to mid-rail, 4.75Vpp (2.38Vpp on each output) will be the output voltage swing capability for 1dB compression. As VOCM is varied from mid-rail, this will cut into the output swing capability.
Response: The input / outputs pins bias to the voltage applied to this pin. This is very useful when using the AD8351 to drive an ADC, as shown in Figure 40 by tying the ADC VREF to VOCM.
Response: I don't think AD8351 is suitable for single ended to differential dc-coupled applications. Here are some DC coupled devices that can do the single ended to Diff conversion for you:
SE to diff devices Parametric Search Table: