Texas Instruments Universal EVM for Single/Dual OpAmps with Shutdown in MSOP/SOIC/SOT-23 Packages OPAMPEVM-SOT23SHDN OPAMPEVM-SOT23SHDN Datenbogen

Differential Amplifier

4-10

Example Circuits

Figure 4–6 shows area 300 equipped with a single operational amplifier
configured as a differential amplifier using a voltage reference and single
power supply.

Basic setup is done by choice of input and feedback resistors. The transfer
function for the circuit as shown is:

V

OUT

+

V

IN

ǒ

R302
R304

Ǔ

)

VREF3

Where

R302
R304

+

R309
R308

The TLV431 adjustable precision shunt regulator, configured as shown,
provides a low impedance reference for the circuit at about 1/2 V3+ in a 3 V
system. Another option is to adjust resistors R311 and R310 for the desired
VREF3 voltage. The formula for calculating VREF3 is:

VREF3

+

1.24

V

ǒ

R311

)

R310

R310

Ǔ

Figure 4–6. Single Operational Amplifier Differential Amplifier with Single Supply Using

Area 300

(

)

µ

µ

Ω

µ