Other Parts Discussed in Thread: TL431, TM4C1294NCPDT, , TLVH431
Internal reference VREFP = VDDA works as expected producing proper MCU temperature, dc current, dc voltage measurements ADC0/1.
With R41 removed and 10Rk in series X11 pin 34 for current limiting 3.3v reference @330ua the VREFA+ = 1vdc but sources 575ua with series 10R0 as VREFA+ tops out at 2.7vdc. Note worthy is the analog comparators ladder resistor chain also source VDDA and are configured in both internal reference and external reference modes.
The external VREFA+ ADC0/1 reference at (TP13) drags down a TL431 precision voltage source limited to 3ma and powered via U5 +3v3 1 amp LDO regulator.
TM4C1294NCPDT data sheet table 27-45 list IVREF of 330.5ua MIN / 440ua MAX @3v3.
Why does EX-TM4C1294XL ADC0/1 VREFP require much more current externally versus internally configured? Is this normal for it to source so much current as it scares me to smoke MCU if hot wire X11 pin 34 without some value of series resistor to maintain current listed in table 27-45?