OA
16-9OA

Figure 164 shows an example of a three-opamp differential amplifier using

OA0, OA1 and OA2. The control register settings are shown in Table 164.

The gain for the amplifier is selected by the OAFBRx bits of OA0 and OA2. The

OAFBRx settings for both OA0 and OA2 must be equal. The gain settings are

shown in Table 165. The OAx interconnections are shown in Figure 165.

Table 164.Three-Opamp Differential Amplifier Control Register Settings
Register Settings (binary)
OA0CTL0 00 xx xx 0 0
OA0CTL1 xxx 001 0 x
OA1CTL0 00 xx xx 0 0
OA1CTL1 000 111 0 x
OA2CTL0 11 11 xx x x
OA2CTL1 xxx 110 0 x
Table 165.Three-Opamp Differential Amplifier Gain Settings
OA0/OA2 OAFBRx Gain
000 0
001 1/3
010 1
011 1 2/3
100 3
101 4 1/3
110 7
111 15
Figure 164. Three Opamp Differential Amplifier
OA1
+
OA2
+
1
2)12(
R
xRVV
Vdiff
=
R2R1
V2
V1
OA0
+
R2R1