We had used T4160NXN7PQB low power version in our design and now we want to use T4081NXN7PQB as a replacement.As we understood that T4240 SENSEGND_CC (Pinball AA33) and SENSEVDD_CC (pinball Y33 ) connection will be provided to respective GND and SUPPLY,but for T4160/T4161/T4080/T4081 (Pinball AA33) ,(pinball Y33 ) are reserved pins.so we have provided pulldown option and the board is working for T4160/T4161 Processor.
We want to understand any other change is required for T4081 processor connection in place of T4160.
As per QorIQ T4240 Datasheet Rev 2,03/2018 in page number 73, comment number 29 for pin details it is mentioned that,
For T4160 (IFC_AD16 pin) may be left floating or pulled up. For T4080 this pin must be pulled to ground. Pull with a 4.7k resistor.(What does it mean?)--------Need some clarity on this.
Page number 234 of the datasheet Notes number 2 it is written that T4241/T4161/T4081 are identical to T4240/T4160/T4080 except they consume less power.(This means No hardware change is Needed,is that correct?)
We need clarification on these points to go ahead with the processor change to T4081 in place of T4160.
> (Pinball AA33) ,(pinball Y33 ) are reserved pins.so we have provided pulldown option
These pins have to be no connect - refer to the QorIQ T4160/T4080 Data Sheet, Table 1. Pinout list by bus.
> For T4160 (IFC_AD16 pin) may be left floating or pulled up. For T4080 this pin must be pulled to ground.
IFC_AD16 selects personality - either T4160 or T4080.
"Pull to ground" means connect to ground through resistor.
Useful reference is AN4559 - QorIQ T4240 Design Checklist: