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
Top 10 Candidates for Next-Gen Storage
What's the next step in the evolution of memory? This...
eetimes.com
A Taste of LabVIEW
I attended an introduction to LabVIEW workshop to get some...
eetimes.com
Designing for Wearables: Tremendous Opportunity but Not Without Challenges
The wearables space is wide open and exploding with opportunity,...
edn.com
Memory Product Round Up: September 2014
Summaries of memory products making news this month, including SD...
eetimes.com
Some Days You're the Pigeon, Others You're the Statue
Are cities still commissioning new statues, or is this practice...
eetimes.com
M2M & IoT Meet Asset Tracking
The advent of highly integrated and low cost Field Programmable...
eetimes.com
Where's the Silicon in Silicon Valley?
An engineer who has experienced firsthand the changes that the...
eetimes.com
Teardown.com Analysis: Apple iPhone 6 Plus
Qualcomm appears but not as RF, and the A8 is...
eetimes.com
Maker Faire Meets the Big Apple
Hundreds of large companies, startups, maker spaces, and scientists converged...
eetimes.com
Why You Can't Judge a Company by Its Version 1.0 Product
You really don't need to spend your valuable time fighting...
eetimes.com
Inside Intel's Gen 8 GPU
Intel recently gave a tour inside the workings of its...
eetimes.com
Australian Crowd Source Equity Funding Report
I have been made aware of this Australian government requested...
eevblog.com
Startup's Piezoelectric MEMS Mics May Take Over
By using piezoelectric diaphragm, Vesper claims its MEMS mics today...
eetimes.com
EEVblog #664 – Peltier TEG Energy Harvesting Experiments
Dave plays around with an energy harvesting kit to see...
eevblog.com
Tesla Model S – Australian Test Drive
Dave test drives one of the first right hand drive...
eevblog.com
What Apple Stuffed Inside iPhone 6 Plus
The iPhone 6 Plus packs a host of new tech...
eetimes.com
Secure WiFi Shield for Arduino Platforms
The Arduino Wi-Fi Shield 101 is designed to enable rapid...
eetimes.com
Digital Level Shifting
Do you need to take your signals to the next...
eetimes.com
Steve Wozniak Reacts to Latest iPhone
Being presented with his very own iCups communications system certainly...
eetimes.com
Five Challenges to FPGA-Based Prototyping
The state-of-the-art has progressed spectacularly since early forays into FPGA-based...
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 +