I am working one of my project called 8 Channel Receiver.
In this project, I have 8 Channel of differential Analog input.
I will get the all the 8 Channel input from external source with the range of 10Vpp as Max .
I have mentioned my design block diagram for your reference.
This differential signal is fed to the PGA AD8253 with selectable range of gain.
After this PGA I am going to remove high frequency components and allowable range of 0 -30khz Band and remove other range of signals. Hence the Output of PGA will be 20Vpp.
Due to the Input Constraints of AD7768 (AD7768 – allow only Differential or pseudo- differential Input with maximum allowable Common mode range is 5Vpp).
I am going to attenuate this signal 20Vpp to 10Vpp using LT1678. Then ,I convert this single ended bipolar 10Vpp to the differential bipolar signal 5Vpp using ADA4922-1.
And also level shift the output signal 2.5V by given REF pin of ADA4922-1.
Hence finally I will get the differential unipolar signal range of 0 to 5V. and fed to the AD7768 ADC.
My questions are below:
- Using AD4922-1: Is it ok for single end to differential Convert?
In this datasheet mentioned, AD4992-1 is Differential 18 bit ADC Driver.
my ADC is 24 bit, Is this AD4922-1 have capable to drive my differential signal ?
- By level shifting of signal of AD4922-1 by Appling 2.5V at the REF pin, Is this right way?
- Is there any part which is equivalent or better than ADA4922-1 please let me know.
Please leave your comments as soon . we are going to release the Schematic design to PCB design.
Thanks and Regards,