Hello TI Support Team,
I am using the TPS51916 in a DDR4 application (1.2V) in DCAP-2 mode with tracking discharge - Mode 0 (using 1kOhm resistor at R7 in schematic photo below). Targeting 6.5A as my limit of the output current.
When picking R1 and R2 for DCAP-2 mode, should I just use equation 6 from the datasheet with 0-ESR? That gets me 20K for my application and matches Webench.
The Rtrip calculations come out to about 12K, but simulations in PSpice seem to indicate that 10K will be closer to the 6.5A limit. What would be TI's take? No damage should occur above 6.5A, but I will start to hit the 10% inductance drop of the selected inductor. I honestly don't even expect to see more than 4.2A.
Is there a target corner frequency for the low pass filter mentioned in the Layout Guidelines on page 29? I am certain that my ESR of the VTT output cap (C8 in the photo) is >2mOhm.
Would TI have an issue with the use of the XGL5050-152MEC inductor from Coilcraft, and would the output capacitance shown in the photo suffice? I have used Murata's simsurfing to get the voltage derating and paracitics for my output caps in order to be a bit more accurate... They are a 47uF and 3x 100uF X5R caps. Wide temp range is not a major concern.
Thank you,
Donald Weaver