TweetDC Biasing & AC Performance Analysis of BJT and FET Differential Amplifier Sub-circuits with Active Loads Any op-amp worth its salt has a differential amplifier at its front end, and you’re nobody if you can’t design one yourself. So, this article presents a general method for biasing and analyzing the performance characteristics of single-stage BJT [...]
Tags: ac analysis, ac performance analysis, active loads, bjt current mirror, bjt differential amplifier, BJTS, CMRR, common mode gain, common mode input impedance, common mode rejection ratio, current mirror, current mirrors, dc biasing, Diff Amps, Differential Amplifiers, differential input impedance, differential mode gain, FET, FET Differential Amplifiers, transconductance
TweetWhy We Need Smith Charts In the world of RF (Radio Frequency) electronics, normal “bench-top” circuit components cease to operate the way they were designed to. This means a normal resistor can become a capacitor, a capacitor can become an inductor, and a normal wire can become a distributed network of inductors and capacitors. This [...]
Tags: smith chart, smith charts, using smith charts
TweetThe frequency response of a BJT or MOSFET can be found using nearly the exact same process, with the only variations being caused by a single resistor and simple naming conventions that differ between the two devices. Before we start let’s think a little bit about what we’re doing: Our goal is going to be [...]
Tags: Basic Electrical Engineering Concepts, BJT, Cadence, Electrical Engineering, Electrical Engineering Concepts, Engineer, MOSFET, Parallel Resistance Formula, pole, PSPICE, transistor
TweetThe following is an explanation of symbol conventions , voltage polarities and current directions for npn and pnp BJTs. The goal is to help understand these characteristics but not on the physical level of electrons and holes. The following figure shows practical operation of each BJT in the active mode. npn or pnp When looking [...]
Tags: base, BJT, collector, Current, Electronics, emitter, npn, pnp, transistor, voltage
TweetBasic BJT Equations: It is also important to know that can be modeled as . These equations are not very informative by themselves so a few examples are demonstrated below. In both examples we will assume is very large. What this means for our calculations is . Since we also assume that . Finding missing [...]
Tags: alpha, base, beta, bipolar, BJT, collector, Current, emitter, junction, npn, pnp, transistor, voltage