Analog Devices UG-397 User Manual page 5

Evaluation Board User Guide
Signal Amplifier
RDAC can be operated as a noninverting signal amplifier
supporting pseudo logarithmic gain. Table 6 shows the available
configurations.
The noninverting amplifier with pseudologarithmic gain is
shown in Table 6, and the gain is defined in Equation 4.
R
 1 
AW
G
R
WB
where:
R is the resistor between the W and A terminals.
AW
R is the resistor between the W and B terminals.
WB
Table 6. Amplifier Selection Link Options
Amplifier Gain
Noninverting Pseudo logarithmic
1
Daughter board
2 Motherboard
Figure 4. Pseudologarithmic Noninverting Amplifier
(4)
R42 can be used to set the maximum and minimum gain limits.
1
Link(DB )
A2 = A3 = A4-A
A1 not inserted
Rev. 0 | Page 5 of 16
R41
1.7kΩ
V
+
IN
C1
–
W2
10nF
W
A2 B2
R42
B A
RDAC
2
Link (MB ) Label
A7 LOC
A6 N-INV
A8 N-INV
UG-397
VOUT2
V Range
IN
0 V to V
DD