Power is applied to the IA (U1) with test points V+, GND, and V– located at the top of the board. For the voltage reference buffer (U2), power is applied using test points OAV+ and OAV–. Additionally, you can tie V+ and V– to OAV+ and OAV– using jumpers J3 and J4 to power U2 and U1 from the same connection.