I'm now using an Xeon E5 1650 instead of the I7. So I stuffed a couple of cheap ssd's into a used workstation with a nice little Xeon and started anew.īut I'm still migrating all the stuff and haven't even fired up Daz, and I'll try and keep up with your feedback, comments and most important all the wonderful art in my watches, but I'm severely lagging behind. OP-AMPs and linear ICs are microelectronic circuits (Integrated circuits).Since I was not all happy with my machines performance lately (The last time I installed it was when W10 just deployed), especially lugging some really old hard drives around, I decided to tackle a new start. These circuits are replacing transistors in electronic circuits just as transistors once replaced vacuum tubes. Use direct coupling (eliminating need for coupling capacitor).Its design eliminates need for emitter by pass capacitor.It can discriminate against common mode signals (Noise or pick up).I – OPERATIONAL AMPLIFIER AND ITS CHARACTERISTICS Most recent general purpose OP-AMPs are BIFETs, combination of FETs and BJTs. OP-AMP is a direct coupled, high gain, high input impedance negative feedback amplifier. The term operation amplifier refers to an amplifier that performs mathematical operations such as addition, subtraction, multiplication, integration, differentiation etc. OP-AMP basically is a difference amplifier, followed by more stages of gain and class- B push-pull emitter follower. The difference amplifier amplifies the difference of two input voltages (inverting and non inverting). The configuration is most suited to Integrated Circuits. It eliminates the need for emitter by pass capacitor. When the voltage applied to two inputs in a differential amplifier is same it is called common mode signal. If the difference amplifier is perfectly symmetrical there is no output with common mode signal. These common mode signals may be due to interference, undesirable pickups or noise etc. The difference amplifier is most popular since it can discriminate against these common mode signals. The Block Diagram representation of an op amp is shown in the Figure (video). Input Stage: Provides most of the gain and sets input resistance. Intermediate Stage: Dual input single ended output. Due to direct coupling between first two stages the dc level of output is much above ground level. Level Shifting: Since the dc output of intermediate stage is higher so level translator is used. This circuit is emitter follower using constant current source. Output Stage: Complimentary symmetry push-pull amplifier provides large output voltage and current swing capability and low output resistance. The schematic symbol of OP-AMP is given in the figure. The positive input (Pin 3) is non inverting i.e. ac input applied produces in phase output. The negative input (Pin 2) is inverting i.e. applied input produces 180 0 out of phase signal at output. It uses dual power supply, +V CC and -V EE. When a piece of wire is connected between a point in the circuit to ground, both voltage and current are grounded. This concept is introduced to simplify the analysis of Inverting Amplifier circuits. This concept has come due to ideal OP-AMP. The circuit shown is of inverting amplifier (Figure shown in video). Since i 2 = 0, the current through R f should be same as i in Since v 2 = 0, so input acts like a ground for voltage but open for current. Virtual ground is like half of a ground, i.e. Short for voltage but an open for current. No current can flow to ground(no current sink).Īlthough it is an approximation, but it gives accurate results for negative feedback circuits.