Chapter III Operational Amplifierseee.guc.edu.eg/Courses/Electronics/ELCT401 Electric Circuits...
Transcript of Chapter III Operational Amplifierseee.guc.edu.eg/Courses/Electronics/ELCT401 Electric Circuits...
Chapter III
Operational Amplifiers
Objectives
• To introduce Operational Amplifiers as linear circuit elements.
• To identify the I-V characteristics of the operational amplifiers.
• To write KCL and KVL equations for the common amplifier
circuits.
• To calculate the gain of cascaded amplifiers’ circuits.
Pin Assignment
Ideal OPAMPs
Ideal Op Amp Applications
The most widely used op amp applications are,
1. The inverting amplifier.
2. The non inverting amplifier.
3. The summing amplifier.
4. The difference amplifier.
5. The voltage follower.
Inverting Amplifier
Vp = Vn = 0
0−𝑣𝑖
𝑅1+ 0−𝑣𝑜
𝑅𝑓
+ 0 = 0
𝑣0
𝑣𝑖= -
𝑅𝑓
𝑅1
The Non-Inverting Amplifier
+
–
vin
+
–
vout
R1
R2
+
–
• Hence, the non-inverting amplifier has a
gained output (> unity) relative to the
resistance ratio
Summing Amplifier
–
+vb+
–
vo
R2
RfR1
va
+
–
+
–
The Difference Amplifier
Voltage Follower
What is the point?
Vo = Vin
Example
• Calculate Vo assuming
• ideal OPAMP
Example
• Show that
The Integrator
The Differentiator