Quantcast Figure 3-45.JFET structure

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
3-39 The elements of one type of FET, the junction type (JFET), are compared with the bipolar transistor and the vacuum tube in figure 3-44. As the figure shows, the JFET is a three-element device comparable to the other two. The "gate" element of the JFET corresponds very closely in operation to the base of the transistor and the grid of the vacuum tube. The "source" and "drain" elements of the JFET correspond to the emitter and collector of the transistor and to the cathode and plate of the vacuum tube. Figure 3-44.—Comparison of JFET, transistor, and vacuum tube symbols. The construction of a JFET is shown in figure 3-45. A solid bar, made either of N-type or P-type material, forms the main body of the device. Diffused into each side of this bar are two deposits of material of the opposite type from the bar material, which form the "gate." The portion of the bar between the deposits of gate material is of a smaller cross section than the rest of the bar and forms a "channel" connecting the source and the drain. Figure 3-45 shows a bar of N-type material and a gate of P-type material. Because the material in the channel is N-type, the device is called an N-channel JFET. Figure 3-45.—JFET structure. In a P-channel JFET, the channel is made of P-type material and the gate of N-type material. In figure 3-46, schematic symbols for the two types of JFET are compared with those of the NPN and PNP bipolar transistors. Like the bipolar transistor types, the two types of JFET differ only in the configuration of bias voltages required and in the direction of the arrow within the symbol. Just as it does in transistor symbols, the arrow in a JFET symbol always points towards the N-type material. Thus the symbol of the N-channel JFET shows the arrow pointing toward the drain/source channel, whereas the P-channel symbol shows the arrow pointing away from the drain/source channel toward the gate.


Electrical News
Last Man on Earth: How Would You Behave?
How do you think you'd behave if you were the...
eetimes.com
Channel Consolidation & Conflict: Back to the Future!
As much as everything changes, everything still stays the same....
eetimes.com
Is Formal Verification Artificial Intelligence?
Artificial intelligence or not, formal verification is a technology that...
eetimes.com
Is Formal Verification Artificial Intelligence?
Artificial intelligence or not, formal verification is a technology that...
eetimes.com
Wearable Cameras Next Boom Market for Image Sensors
Annual shipments of wearable cameras will surpass 30 million units...
eetimes.com
Resistive RAM Memory is Finally Here
Resistive RAM's low power consumption and small cell area make...
eetimes.com
NVM Express SSDs Hit Servers, Workstations
HGST begins shipping its Ultrastar SN100 series for servers announced...
eetimes.com
Moore's Law Demise: Maybe It's a Good Thing
Moore's Law will celebrate its 50th anniversary on April 19,...
eetimes.com
The GaN Era Approaches
Gallium nitride possesses many characteristics that will allow production of...
eetimes.com
Making Wireless LoRa Design Easier, Faster
Microchip has a pre-certified coin-cell sized module to accelerate deployment...
eetimes.com
Engine Yard Pivots Toward Container Management
New Engine Yard CEO Beau Vrolyk is moving the company...
eetimes.com
Transceiver Supports Dual 2.4 GHz IoT Networks
Industrial applications, home automation, and the like often need multiple...
eetimes.com
Moore's Law @50 in the News
Here's a sampler of some of the best of the...
eetimes.com
When Blueprints Were Really Blue: Is Engineering Becoming Less Satisfying?
Back then, working as a professional EE was like being...
eetimes.com
MINI Giving Drivers a Peek at 'Augmented Reality'
Although most drivers have yet to embrace the idea of...
eetimes.com
eevBLAB #9 – Meet Dave
Meet Dave2, the first EEVblog employee....
eevblog.com
Qualcomm to Leverage Monolithic 3D for Smartphones
Qualcomm is looking to leverage Monolithic 3D IC technology to...
eetimes.com
Full Human Head Transplant May Be Closer Than You Think
Suddenly, some of the things we read in science fiction...
eetimes.com
Automotive Chip Reliability: A Matter of Design Methods
Up to 90% of all innovations today are generated through...
eetimes.com
Paper Memory Ready to Roll
Researchers at the Finish VTT Technical Research Centre have demonstrated...
eetimes.com
 


Privacy Statement - Copyright Information. - Contact Us

comments powered by Disqus

Integrated Publishing, Inc.
9438 US Hwy 19N #311 Port Richey, FL 34668

Phone For Parts Inquiries: (727) 755-3260
Google +