Op Amp Circuits

This article is a collection of different Op Amp circuits. The term “OP AMP” or “OPAMP” stands for – Operational Amplifier. Operational Amplifier (Op Amp) is a type of voltage amplifier that provides thousands output gain more than the potential difference which is applied at it input(s). This output can go up to hundred thousand and more (100,000+) compared to the one at its inputs in an open loop state.

An open loop state of an op amp is a state where there is no external feedback from its output to the input. For these reasons, Op Amps Integrated Circuits are mostly used in Pre Amplifier Circuits.

Usually, an ideal Operational Amplifier (Op Amp) has two (2) differential inputs and one (1) single output. The differential inputs are Inverting and Non Inverting input. Inverting input with negative voltage is indicated by the symbol (-) while the Non Inverting input with positive voltage has (+) symbol.
Below are some Circuits using OP AMP Integrated Circuits (ICs)

TL072 Op Amp Preamplifier Circuit

TL072 Preamplifier circuit Parts

• C1 = 1µF (Electrolytic polarized Capacitor)
• C2 = 0.1nF (Ceramic Non Polarized Capacitor)
• C3 = 10µF (Electrolytic polarized Capacitor)
• VR = 100KΩ Potentiometer
• R1 = 100KΩ (Fixed Resistor)
• R2 = 1KΩ (Fixed Resistor)
• R3 = 1.8MΩ

741 OP AMP Preamplifier Circuit

Among the OP AMP circuits, the Op Amp IC 741 is very common. This IC is also applicable in preamplifier circuits. In the circuit is LM manufacture’s version however, you can use any of the 741 manufacturers for the circuit.

Parts of the LM741 preamplifier circuit

• C1 = 1µF (Electrolytic)
• C2 and C4 = 10µF (Electrolytic)
• C3 = 47nF (Ceramic Non polarized capacitor)
• R1 = 1KΩ
• R2 and R3 = 22KΩ
• R4 = 100Ω
• R5 = 220KΩ
• VR = 50KΩ (Potentiometer)

See also; LM386 amplifier circuit

JRC4588 OP AMP Low Pass Filter 

I will be updating and uploading  more Op Amp Circuits here, you can always come back for the updates