SLVU006A Datasheet, PDF (24/28 Pages) Texas Instruments – UNIVERSAL OPERATIONAL AMPLIFIER EVALUATION MODULE

Noninverting Amplifier
3.5 Noninverting Amplifier
Figure 3–4 shows area 400 equipped with a single operational amplifier
configured as a noninverting amplifier with single supply power input. Note the
pinout for the operational amplifier in area 400 follows the TLV2771 type
pinout.
Basic setup is done by choice of input and feedback resistors. The transfer
+ ǒ ) Ǔ ) ^{function for the circuit as shown is:}
VOUT
VIN 1
R405
R407
VREF4
Note that the input signal must be referenced to VREF4.
To cancel the effects of input bias current, set R409 = R405 || R407, or use a
0 Ω jumper for R409 if the operational amplifier is a low input bias operational
amplifier.
The TL431 adjustable precision shunt regulator, configured as shown,
provides a low impedance reference for the circuit at about 1/2 V4+ in a 3 V
system. Another option is to adjust resistors R415 and R416 for the desired
+ ǒ ⁾ Ǔ ^{VREF4 voltage. The formula for calculating VREF4 is:}
VREF4
1.24
V
R415 R416
R416
Figure 3–4. Non-Inverting Amplifier with Single Supply Using Area 400
V4+
V4+
GND4
V4–
C404
0.1 µF
C403
1 µF
C409 C410
401–
Jumper 402 – to VREF4
402–
403+
Power Supply Bypass _V4–
404+
R406
R407
R408
R409
R418
C405
C412
R419
R405
V4+
5–
3+
4
4
2 ^U401
( ^{VOUT = VIN +1}
4OUT
) ^{R405 + VREF4}
R407
V4–
V4+
R414
2.2 kΩ
VREF4 = 1.24 V
+
Vin
–
R415
C
R
A
R416
U402 = TLV431ACDBV5 _{Input Signal With}
Reference to VREF4
C411
R417
C406
R409 = R405 II R407,
or Short if Using Low Input
Bias Op Amp
Voltage Reference
3-6
Example Circuits