I'm afraid that without these diodes we may surpass the +-1.5v differential
mode input voltage at the absolute maximum ratings.
The ADA4898-2 has a input stage which allows for a maximum differential voltage
of ±1.5V. This voltage is calculated for the complete input stage of the
powered ADA4898-2. Kindly find the “Absolute Maximum Ratings” of the datasheet
(http://www.analog.com/ADA4898-2) on page 5. The Absolute Maximum Ratings is a
stress rating only. Stresses above those may cause permanent damage to the