EC5821 datasheet(5/11 Pages) E-CMOS

5 / 11 page

10MHz, Low Power, CMOS,

Rail-to-Rail Operational Amplifier

EC5821

E-CMOS Corp. (www.ecmos.com.tw)

3K29N-Rev.P001

Page 5 of 11

The amplifier in Figure 5 is a high input impedance differential amplifier with gain of R2/R1. The two differential

voltage followers assure the high input impedance of the amplifier.

Two-Op-Amp Instrumentation Amplifier

EC5821 can also be used to make a high input impedance two-op-amp instrumentation amplifier as shown in

Figure 6.

Figure 6. Two-Op-Amp Instrumentation Amplifier

Where R1=R3 and R2=R4. If all resistors are equal, then Vo=2(VIP-VIN)

Single-Supply Inverting Amplifier

The inverting amplifier is shown in Figure 6. The capacitor C1 is used to block the DC signal going into the AC

signal source VIN. The value of R1 and C1 set the cut-off frequency to ƒC=1/(2πR1C1). The DC gain is defined

by VOUT=-(R2/R1)VIN

Figure 7. Single Supply Inverting Amplifier

Low Pass Active Filter

The low pass active filter is shown in Figure 8. The DC gain is defined by –R2/R1. The filter has a -

20dB/decade roll-off after its corner frequency ƒC=1/(2πR3C1).

EC5821 Datasheet(PDF) 5 Page - E-CMOS Corporation