Search results
An Operational Amplifier, or Op-amp for short, is fundamentally a voltage amplifying device designed to be used with external feedback components such as resistors and capacitors between its output and input terminals.
The Open-loop gain called the Gain Bandwidth Product, or (GBP) can be very high and is a measure of how good an amplifier is. Very high GBP makes an operational amplifier circuit unstable as a micro volt input signal causes the output voltage to swing into saturation.
Operational amplifiers (op amp) are linear devices that have all the properties required for nearly ideal DC amplification and are therefore used extensively in signal conditioning or filtering or to perform mathematical operations such as adding, subtracting, integration, and differentiation.
For the inverting amplifier the multiplication constant is the gain −. Op amps may also perform other mathematical operations ranging from addition and subtraction to integration, differentiation and exponentiation.1 We will next explore these fundamental “operational” circuits.
negative feedback around a high gain DC amplifier would produce a circuit with a precise gain characteristic that depended only on the feedback used. By the proper selection of feedback components, operational amplifier circuits could be used to add, subtract, average, integrate, and differentiate.
Op amps with a built-in capacitor are termed compensated, and allow circuits above some specified closed-loop gain to be stable with no external capacitor. In particular, op amps that are stable even with a closed loop gain of 1 are called unity gain compensated .
The inverting operational amplifier is basically a constant or fixed-gain amplifier producing a negative output voltage as its gain is always negative. We saw in the last tutorial that the Open Loop Gain , ( A VO ) of an operational amplifier can be very high, as much as 1,000,000 (120dB) or more.
