Darlington transistor

Figure 10. Diode/Darlington-transistor circuit of a series (OEM) charger [39].

Many semiconductor manufacturers have data sheets and PSpice models available online for easy access by engineers. In this section we will show how to obtain those models so that we can use them in a simulation. The types of models we will show can be split into two types. The first type of models are primitives that use only a. model statement. Examples of these are diodes, bipolar junction transistors (BJT), and MOSFETs. The second type of models we will download are subcircuit models such as op-amps, IGBT s, Darlington transistors, and MOSFET subcircuit models. 

Other temperature transducers employed in calorimetric analyzers include Peltier elements, Darlington transistors, and thermopiles. Thermopiles can be made in very small dimensions using current semiconductor technology and are less flow-sensitive than thermistors, though the latter provide higher temperature resolution. 

The designer must check the power dissipated by the pass transistor (the Darlington transistor) to determine the heat sinking requirements. 

Figure 6.16 Circuit symbol for a two-junction transistor or power Darlington...

This amplifier has two problems. The first is that most op-amps cannot drive this push-pull amplifier when it is driving an 8 2 load. The second is that the transistors turn on and off. This adds a phase delay, which can cause the amplifier to oscillate. The Darlington push-pull amplifier on page 373 works much better. ... 

Darlington NPN Subckt Subcircuit model for a Darlington NPN transistor... 

The second alternative is an electronic load. This device is a circuit that has a controllable switch (typically a Darlington configured pair of bipolar transistors or a MOSFET) that can be modulated to conduct any level of current the user desires. An example of an electronic load circuit is presented in this chapter. The electronic load will be constructed piece by piece and tested separately. When all the pieces are constructed and simulated, the whole sum of the electronic load can be assembled and tested as a unit. 

One problem, or should we say challenge, in designing this type of circuit is to ensure that the Darlington pair transistors are not overstressed by causing them to dissipate too much power. The maximum power the transistor can dissipate decreases with increasing collector-emitter voltage. 

Darlington pain A configuration of two transistors, the emitter of one feeding the base of the other, used to increase gain. 

One transistor can feed its amplified signal directly to another, and this is called the Darlington circuit, named after its innovator. If each transistor has a gain of about 100, the overall gain is about 10,000. They can be bought in a single... 

Transistor, NPN Darlington pair, NPN Piezo transducer Diode, silicon, 1N914 ... 

Q103 can be replaced with two transistors in Darlington connec t ion. 

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