Typical Application Circuits

DIFFERENTIALAMPLIFIER

Figure 5 Differential Amplifier

The circuit shown in Figure 5 performs the difference function. If the resistors ratios are

equal R4/R3 = R2/R1, then:

VOUT = (Vp – Vn) × R2/R1 + VREF

INSTRUMENTATION AMPLIFIER

VOUT = (V1 – V2) × (1+ R1/R2 + 2R1/RG) + VREF

Figure 6 Instrumentation Amplifier

The AD854xA family is well suited for conditioning sensor signals in battery-powered

applications. Figure 6 shows a two op-amp instrumentation amplifier, using the AD854xA

op-amps. The circuit works well for applications requiring rejection of common-mode noise

at higher gains. The reference voltage (VREF ) is supplied by a low-impedance source. In

single voltage supply applications, the VREF is typically VS/2.

1.1MHz, 85µA, CMOS, RRIO Operational Amplifiers

UMW

AD8541,AD8542,AD8544

R

www.umw-ic.com

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UTD Semiconductor Co.,Limited