adc front end design using ada4930 -2

Hi nias, 

ADA4930-2 can be configured as a single-ended to differential driver for the LTM9011. The input signal will need to be attenuated and level shifted to match the ADC's selected input range and common-mode voltage.

Before recommending a circuit, could you please clarify the following?
- What is the signal frequency or required bandwidth?
- Is the 0-10V signal unipolar and DC-coupled?
- Are you planning to use the LTM9011's 1 Vpp or 2Vpp input range?

Best Regards,
Ian

70Mhz is possible bandwidth, as of now. yes the input to the ada4930 is from amplifier(mscf16) is having following features

amplifier Output amplitude: 0 to 10 V at 1 kΩ  with DC-Offset: VDC ← 5 mV, . the amplifier has 50 output imedance and 1k load impedance . and this is the input to pur ada4930... so we need to attenuate the input. i can you ada4930 with single supply +5v or 3.3v  plz suggest 

i want to use ltm9011 with 0-1v range to have future leverages. 

 plz suggest

Hi nias,

Thanks for the additional information and schematic. Since the MSCF16 output is 0-10V at a 1k ohm load with 50 ohm output impedance, I would recommend operating the ADA4930-2 from a 5V supply. This provides more input common-mode headroom for the required attenuation and level shifting.

Please note that the LTM9011 1V input range refers to 1 Vpp differential, with the inputs centered around the ADC VCM voltage.

I also noticed that PD1 and PD2 are biased at approximately 2.5V by the two 2.2k ohm resistors. For a 5V operation, the ADA4930-2 requires PD > 3V to guarantee the enabled state, so these pins should be pulled high if power-down control is not required.

Best Regards,
Ian

ok i ll connect PD to >3v but what about the rest of the circuit, as i wan to know about the values for RF and RG in single ended single supply mode of operation along with the attenuation part of the input stage of the circuit ....

I hope after removing one 2.2k to GND the ciruit is completly fine