The data sheet recommends starting with RS15 equal to 100K and calculating RS16 for our target output voltage of 1.1V.
RS16=RS15 x 0.8V/Vo - 0.8V so 266K=100K x 0.8V/1.1V - 0.8V
I notice that when probing the VSense Pin on this part, using a 6pF probe, that it will cause a core reset on the DSP. This implies to me that it is very sensitive. Is this normal? If I lower the values of R1 and R2 from 266K/100K to 26.6K/10K, this effect goes away.
Question 1: Is it necessary to keep R1 at 100K or can it be lowered?
Question 2: The layout has US3 and RS16 on the top of the board and RS15 on the bottom, connected through 2 vias. Are the vias combined with the larger values of RS15 and RS16 causing the reset?
Question 3: Is this effect an artifact and no cause for concern?