Tool/software:
I am simulating the LM2901 using the pspice simulation model. I note in the subckt model that it states, "* If the input goes beyond the recommended input voltage range, the output will float to mid supply
* If the supplies goes beyond the recommended supply voltage ranges, the output will float to mid supply
* The real device will NOT do this."
I also note in the datasheet also stated, "4) The voltage at either input or common-mode must not be allowed to go negative by more than 0.3 V. The upper end of the common-mode voltage range is VCC+ – 1.5 V; however, one input can exceed VCC, and the comparator will provide a proper output state as long as the other input remains in the common-mode range. Either or both inputs can go to VCC MAX without damage."
In the simulation, I have the non-inverting input held at a fixed 2.5V reference voltage. VCC is 5V. The inverting input is > 3V violating the VICR requirement over the full temperature range (VCC - 2V). In the simulation the output is floating to 2.5V as stated in the pspice lib file. If I reduce the inverting input below 3V, then the output swings fully from 0V to ~5V as desired.
My question is given the statement in the datasheet quoted above (That proper output state will ensue as long as the other input remains in the common mode range), will the real actual part behave properly in hardware under the same VICR conditions as the simulation? i.e. one input at +2.5V, other at +4V, VCC at +5V.
My follow up question is if not a problem with the real device, why have a simulation model which does not represent the real device?
