1. There is a typical value of internal reference accuracy, do we have the max and min value for this spec? As I understand, the accuracy of the reference should be calculated by: accuracy=(Max-Min)/typ*100%, so we must know the max and min value.
2. when using external reference mode, there is a requirement that V_REF should < VDD, so V_REF must ramp up after VDD and ramp down before VDD. Is there any explanation for this requirement? As it is not easy to design a circuit to meet this requirement, can you provide some guidance on this?