BJT、JFET、MOS管，最基础的3种三极管。在原理上，他们的共性 …
网页2022年4月22日 · BJT的关键变量是Vbe、Vce、Ic，JFET与MOS管的关键变量都是Vgs、Vds、Id。. 由这些具体可以概括出： 三极管需要处理的变量都是3个，即控制量、主通道电压、主通道电流。. 做数据拟合的时候，3个变量的关系是很难处理的，都会想办法先踢掉一个，简化为2个变量的 ...
BJT - Common Emitter - exact RE calculation - All About Circuits
网页2021年5月24日 · Hi there, in a common emitter circuit, I calculate the RE ( Emitter Resistor) and RC with. Ib = Ic / BF. R3 = (Vcc - Uce - Ure) / Ic. RE = Ure / (Ic + Ib) But these Formulas do not consider the internal resistors rb and rc. A comparison with Qucs and LTSpice confirms this. ,The BJT Model in this case is.
BJT transistors as voltage-controlled devices - All About Circuits
网页2008年11月28日 · Certainly a BJT needs base current to flow for it to operate, but this is really an annoying imperfection rather than the basis of operation. I appreciate this may take some digesting; far too many textbooks say something like "a small current flowing into the base controls a much larger current flowing into the collector".
BJT transistor storage time - All About Circuits
网页Jun 26, 2015. #4. Storage time (ts) is the time required for the BJT to come out of saturation. This is the time required for the VC to reach 10% of its high-state value (Vcc) I do some real world measurements of this circuit. With anti-saturation diode (I do not have any Shockley diode). But speed-up capacitor will also help.
Saturation of a BJT - All About Circuits
网页Oct 2, 2011. #5. In a nutshell, "saturation" for a BJT is the point where a further increase in base current will not result in a corresponding increase in collector current. That's because Vce is as low as it's going to go for that particular Ic. You might find it …
LTspice avalanche bjt models - All About Circuits
网页5. Jun 6, 2023. #1. Hi all, I'm writing since I need to simulate on Spice the breakdown effect of avalanche BJT transistors. Now, the Gummel-poon model does not describe this phenomenon, so I came across several options. The first one is the VBIC model, which should be supported by LTspice, but it is hard (if not even impossible) to find some ...
How do you turn on an NPN BJT Transistor? | All About Circuits
网页2016年10月8日 · The Vebo (Emitter Base Voltage) is the positive voltage to be applied to the Base, to turn the NPN BJT Transistor on, connecting ground to Emitter. The Vceo (Collector Emitter Voltage) is the Maximum voltage I can have as my load (Collector to Emitter). The Ic (Collector current) is the Maximum current I can switch.
Replacing a BJT with a FET - All About Circuits
网页Oct 13, 2015. #1. In a simple ideal BJT amplifier the input signal I b I b is linearly amplified: I c = βI b I c = β I b. But if you replace the BJT with a FET, the input signal V gs V g s is amplified by the square: I d = K(V gs −V th)2 I d = K (V g s − V t h) 2. So really you can't just replace a BJT with a FET, right?
BJT vs MOSFET vs IGBT - All About Circuits
网页2016年4月13日 · The BJT (and I assume IGBT) are unidirectional and for the most part are fully off, when they are off. However the body diode is great for controlling something with inductance (motors, solenoids, relays, etc) as the back EMF generated when it is turned off can use it as a free wheeling diode, which reduces complexity and part count.
Re-biasing discrete bjt small signal preamp - All About Circuits
网页8. May 27, 2024. #1. I came across this phono preamp which takes in small (~5mv) audio frequency signal from a turntable and amplifies it by ~38db. The first stage transistor (TR1) is running at a very low Vce (1.5v or less). This places the Q point at the very fringe end of the vce-ice/ib curve almost near the knee of the curve.