31 UREF Reference Output

The UREF feature is used to provide a voltage reference for many applications including biasing op amps and touch guarding. UREF provides a reference voltage to internal nodes and to an external, dedicated pin. A high-level diagram is shown in Figure 31-1.

UREF is implemented as a unity-gain non-inverting buffer. The feedback connection directly connects the amplifier output to the inverting input. The amplifier non-inverting input can be connected to multiple signals, shown in Table 31-2.