It's LM108 and LM112 (internally compensated) and there is admittedly no trick there. It has 1nA enter bias that is rather secure with temperature as in many bipolar opamps because β truly increases with temperature. Afterwards iterations like LT1008/LT1012 or OP97 pushed it down to Asides from its wide range https://pindiodeswitch91357.isblog.net/the-5-second-trick-for-pin-diode-switch-51320735