Activity for LvW
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Answer | — |
A: Design high -pass filter with 2 points of the bode plot Miss Mulan - I am a bit late with my answer. Nevertheless - there is formula which gives you the necessary filter order "n" - as a function of two frequencies and both associated damping figures. If applied to the most simple case (Butterworth approximation) the result is n>1.2 Hence, a 2nd-... (more) |
— | over 1 year ago |
| Answer | — |
A: Results of analysis of Hartley oscillator dont make sense MissMulan - at first, you should show which nodes are connected (crossing points). Secondly, where are the voltages Vo and Vin in your diagram? Please keep in mind, that it is essential to OPEN the feedback loop at a suitable point for injecting a test signal. Then, you can/must analyze the LOOP G... (more) |
— | almost 2 years ago |
| Answer | — |
A: Re model of transistor is the same in 2 different configuration I never would recommend to use the "re model" for a BJT. The reason is as follows: The BJT is a voltage-controlled device (Ic is controlled by Vbe and the base current is an unwanted by-product). Hence, the characteristic transfer parameter is the transconductance gm=d(Ic)/d(Vbe)=Ic/Vt.. The ... (more) |
— | almost 2 years ago |
| Answer | — |
A: Find feedback of circuit I must admit that your question (the described problem) is an interesting one. Speaking about the circuit (without consideration of the parts values), there are two feedback effects: At first, the resistor R1 provides negative feedback resulting in a low closed-loop gain slightly below unity. S... (more) |
— | over 2 years ago |
| Answer | — |
A: Help with differential to single ended voltage converter Question: What is the purpose of the current mirror? Answer: It allows to combine the current changes in BOTH transistors (T1, T2). Explanation In a classical differential amplifier (with separate collector resistances for T1 and T2) we must use the difference between the collector voltages or... (more) |
— | almost 3 years ago |
| Answer | — |
A: Using FET based followers and design rules "Also, if there is a way to control this drop (without using an oamp), what are the design rules, or perhaps the rules of thumbs ?" "I reformulate this question:do you see any reason to use a FET follower?" (1) As outlined by Olin Lathrop, the voltage drop (that means: The potential differenc... (more) |
— | over 3 years ago |
| Question | — |
Usage of modern active building blocks In the past, a large number of new active building blocks have been proposed and published by many researchers all over the world. In most cases, these new building blocks were used for realizing novel filter and/or oscillator circuits. In addition to the well known amplifier types Operational... (more) |
— | over 3 years ago |
| Answer | — |
A: Why Ib=const. for BJT output characteristics Ic=f(Vce) My Answer: There are only practical reasons for a representation with Ib=const. These characteristics are primarily used to determine the DC working point (Ico, Vceo) - together with the working line (resistors Rc and Re). Would it be helpful and useful to be able to read the corresponding ... (more) |
— | over 3 years ago |
| Question | — |
Why Ib=const. for BJT output characteristics Ic=f(Vce) Introduction: In some books and other technical papers (also from universities) it is - surprisingly - still claimed that the bipolar transistor (BJT) would be a current-controlled element. This is simply stated - without any explanation or proof (which I think is impossible). But of course, the... (more) |
— | over 3 years ago |
| Answer | — |
A: Purpose of emitter resistor in a common collector amplifier In most cases, the common-collector stage (emitter follower) is used as a buffer stage (unity gain). It is, therefore, an independent stage, whose mode of operation should not be determined by the next stage (which is to be decoupled). That means: Even without a connected load this stage should o... (more) |
— | over 3 years ago |