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Input dynamic voltage range of ADC

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monoj

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I am using an ADC(AD9042, 40MSPS) to digitize the incoming analog signal. This ADC is having input dynamic range of -0.5volt to +0.5volt, i.e. 1 volt. Now I have analog unipolar pulse at the input, and because of the ADC input range limitation, I am able to use only 0 to +0.5volt input range of the ADC. So how to use or utilize the full input dynamic range of this ADC or how to convert the input unipolar pulse into a bipolar one ?
By the way, I have to stick to this particular ADC as it is the only space qualified ADC available and meeting our other requirements.
 

Hi,
you have to insert an Opamp with offseting voltage of 0.5V for your rabge of +/- 0.5V...
Small problem, that best offseting becoms you if its a inverting circuit.
K.

Added after 2 minutes:

Tell us pls, what for an driver amp your ADC has, trhan maybe its simplest to adapt for +/- Input...
 

but this DC offset will be blocked by the capacitor at ADC input. so effectively only that 0.5V will reach to ADC.
 

Hi,
I think not.
If your ADC has a C-coupling, that means its range is, self the IC/after C-Coupling, i.e. at + 2.5V(Uref)...
K.
 

AC coupling of the ADC input is an option but not the only way to operate the device. For pulse signals with asymmetrical duty cycle,
DC coupling is more suitable I think. All possible variants are discussed in the datasheet.
 

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