e2e,
The question is related to the corner frequency and BW of TSA5A3159. I understand the typical value for bandwidth is 100Mhz. I would like to understand the minimum bandwidth value over the full temperature range.
I understand TI cannot guarantee the minimum BW, since it is not measured in the datasheet, nevertheless, is it possible to share the data of the BW at min-max temperature range, data by design , or share the distribution across many units?
Thank you,
Adam
Hello Adam,
Please understand that when designing systems that are bandwidth sensitive, there are special routing techniques one must follow (i.e. shortest possible trace route, minimize parasitic, etc.). These things are key to having the best possible performance.
With that being said, we currently do not have any in house boards ready for such tests and we do not normally characterize bandwidth outside of typical.
However, I was able to gather a PCB from Proto Advantage and put it together with a perforated board to run these tests under the temperature of -40C, 25C and 125C.
Please see below for the board I used for testing:
Top View:
Bottom View:
You will note from the bottom that i tried as much as I could to make sure the pins where the signals traveled through were as close as possible to the SMA's which went to my vector network analyzer (VNA). As you can imagine, there are still plenty of parasitic that effect the performance of my system still.
I have attached the S-Parameters pulled from the VNA which show that despite these challenges, the device still has a bandwidth(-3dB point) roughly around 100 MHz. You will want to look at S12.
-40C:
TS5A3159_Q1_SPARAMETERS_M40C.S2P
25C:
TS5A3159_Q1_SPARAMETERS_25C.S2P
125C:
TS5A3159_Q1_SPARAMETERS_125C.S2P
Thank you,
Louie
Hello Adam,
I would like to stress again that the measurements I took are not the most ideal, but just to give us a rough idea of what our bandwidth is and how it changes with temperature.
With that being said, the BW at all three temperatures remain around the same point (98MHz at -40C and 100MHz at 125C). Please see the attached plot below. You will note that there are some fluctuations in the measurement, but as mentioned above, this is because these tests were done on a perforated board (not ideal for these type of measurements due to parasitic) so these slight fluctuations were expected.
Also a note for future readers, .S2P files can be opened with any text editor, I usually use Sublime Text as it has built in highlighting short keys that I like using.
Thank you,
Louie
