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AD8131 Output Voltage Swing when powered single-ended

Question asked by tom.usenet on Jan 16, 2012
Latest reply on Jan 20, 2012 by AndyR

I'm working on a design with an AD8131 powered from 0V and 5V.

 

It has the Vocm set to 2.5V.


The only specification I can find in the data sheet on the maximum output level is in Table 1:

 

25°C, VS = ±5 V, VOCM = 0 V, G = 2, RL, dm = 200 Ω,

Output Voltage Swing  Maximum ΔVOUT; single-ended output −3.6 to +3.6 V

 

That is within 1.4V of each power rail.

 

For supplies of 0V and 5V, does that convert to +1.4V to 3.6V?

 

Given I'm driving the chip in normal "gain = 2.0 mode" from an input signal referenced to ground (NTSC video), then the maximum input signal level I think it will handle is 1.1V. That would result in a positive output signal from 2.5 to 3.6 and a negative output from 2.5 down to 1.4.

 

The AD8131 is specified to run from 2.7V to 11V. I don't think the "1.4V from the rails" figure can apply over the whole range as that would require a minimum power supply of 2.8V to deliver no output swing at all!

 

Is there a specification of the output drive level over 2.7V to 11V?

 

Thanks

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