RC4277
PRODUCT SPECIFICATION
5
Typical Applications
(continued)
Figure 3. Precision Absolute Value Circuit
Figure 4. High Voltage Differential Amplifier
Figure 5. Polarity Changing Gain Controlled Amplifier
Figure 6. Gain Controlled Amplifier Transfer Function
65-4234
1/2 4277
A
-15V
+15V
2
1
8
4
3
1/2 4277
B
-15V
+15V
6
7
8
4
5
R5
10K
R4
10K
R3
10K
D1
D2
0V to +10V
R2
10K
R1
10K
V
IN
V
OUT
V
A
±
10V
IN
V
OUT
A
V
= R4
65-4427
R5
R1 = R5 = 10 R2
R2 = R3
R4 = R5
R1
50K
5K
(+)
R2
5K
R3
5K
R4
5K
5K
R5
50K
V
(-)
1/2
4277
1/2
4277
Note:
This circuit can tolerate input voltages that
exceed the 4277’s supply voltage rating as long as
the slew rate do not exceed the op amp's slew rate.
n
0.5
1
X
-n
V
OUT
V
IN
R3 POT
Position
65-3062
V
IN
V
OUT
= 2(2X-1)
65-4428
R1
R/n
xR3
R2
V
OUT
1/2
4277
R/(n-1)
R