This thread has been locked.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.
SE-TF-Diff-ADS_01_11_2019.TSCPart Number: ADS4222
Please suggest the front end circuit to connect ADS4222,
Currently designing an custom board in which the single ended pulse signal has to be isolated.
The Pulse duration is 1us to 6us, which is having amplitude of 0 to +10V with 50 ohm impedance.and Frequency of the signal 150KHZ to 10MHZ .
so transformer has been chosen to isolate from primary to secondary
The question is how to step down the voltage from 0 to +10V to 0 to 1V ? as ADS4222 supported is Max 2Vp-p
I went through few application notes from TI but am not able to come up with solution. Which method to use,
1) A transformer having Primary to secondary with 4:1 ratio from coilcraft (SWB1010-SML ) then connect to differential amplifier with unity gain (THS4500) to ADS4222
2)A Transformer with 1:1 ratio (WBC1-1TL) and voltage divider circuit at secondary side (attached the TINA file) then connect to differential amplifier with unity gain (THS4500) to ADS4222
3)To Use an Inverting amplifier attenuate the signal and connect to the primary side of transformer with 1:1 ratio and then connect to differential amplifier with unity gain (THS4500) to ADS4222
4)To Use an Inverting amplifier attenuate the signal and connect to the primary side of transformer with 1:1 ratio and connect using transformer coupled path as in Evaluation schematic circuit of ADS4222
ADS4222 is connected to FPGA using CMOS outputs.
The clock signal is driven from FPGA LVCMOS 65MHZ to ADT4-1WT Minicircuits 50ohm single ended to differential
Attached the TINA circuits. (issue: Differential Output swing is not as per the datasheet, please let me know what to be corrected)
I Purchased ADS4222EVM and TSW1400EVM , before testing it . it would be better for me to fix the front end circuit and test it. Request to suggest ASAP.
How about using an in-line attenuator or resistor pie network to drop down the voltage before it connects to the transformer? I would also send this post to the amplifier forum to see if they have any suggestions.
We are glad that we were able to resolve this issue, and will now proceed to close this thread.
If you have further questions related to this thread, you may click "Ask a related question" below. The newly created question will be automatically linked to this question.
In reply to jim s:
Thank you for valuable suggestion.
I have attached the circuit and output for review (circuit with pi network of ideal values considering source 50 ohm and load 50 ohm). Please let me know for any corrections.
also i will wait for Amplifier team recommendations.
In reply to chiranjeev N:
As long as the INP/M are within the limits of the data sheet, you should be Ok.
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.