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The main distinguishing feature of the TL Op-Amp is that they incorporate high-voltage JFET and bipolar transistors which helps the transistor to have very high input impedance and low bias current. Also this Op-Amp has low noise and harmonic distortion making it an ideal choice for audio pre-amplifiers. If you are curious to learn about few application circuits of this IC then you can read through how LM is used since both the IC shares the same applications.
There are a plethora of application circuits for Op-Amp each having its characteristics and significance in its own way. But every Op-Amp designs will have some common design considerations or tips which are common among them and we will discuss the same further.
Inputs: Op-Amps are known for its high input impedance, meaning it will not draw any current or disturb the signal that is being given to the Input pin. The input stage of an Op-Amp is mostly complex since it involves many stages. The Input common-mode range value must be considered while supplying voltage signals because the input voltage should never exceed the rail voltage else it will create a latch-up condition which in return will create a short circuit of the supply voltage and thus damaging the circuit permanently.
Also the difference between the voltage values of the Inverting and the Non-Inverting pin should not be more than the Differential Input Voltage Rating. Output: The TL is not a rail to rail Op-Amp hence the output voltage will not reach the maximum positive or maximum negative voltage when saturated. Also remember that a saturated Op-Amp will comparatively draw more current and thus results in power loss. A Closed-Loop system provides feedback to the input this limiting the gain value of the Op-Amp and the noise associated with it.
A Negative feedback is commonly preferred, since it has predictable behaviour and stable operation. In those case it is very important to terminate the Unused Op-Amp properly. Else, the unused pins will develop some stay capacitance which might pick up noise and affect the performance, also non terminated Op-Amps will consume more power thus decreasing the efficiency of the design.
There are many ways to terminate an Op-Amp based on your design, but the most common used method is shown below. Here the Op-Amp is operating between the voltage range Vdd and Vss.
To terminate the Op-Amp the Inverting pin of the Op-Amp is connected to the Output pin and the Non-Inverting pin is provided with a constant voltage source. This constant voltage could be of any value but must be within the limits of supply voltage Common mode Voltage Range. Circuit requiring high input impedance Buffer application Integrator, Differentiator, Summer, adder, Voltage follower, etc.
SGS Thomson Microelectronics