This program uses the SOT-23-6 package.For precise voltage measurements, 0.1% is the tolerance.There is a part with 6 pins that have been settled.There is 2.5V voltage output.
LT6654BHS6-2.5#PBF Features
0.1% Tolerance
LT6654BHS6-2.5#PBF Applications
There are a lot of Analog Devices, Inc. LT6654BHS6-2.5#PBF Voltage Reference applications.