Quantcast Tunnel Diode Devices - Continued - 14183_122

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
2-42 mechanical action called TUNNELING. Tunneling causes the negative-resistance action and is so fast that no transit-time effects occur even at microwave frequencies. The lack of a transit-time effect permits the use of tunnel diodes in a wide variety of microwave circuits, such as amplifiers, oscillators, and switching devices. The detailed theory of tunnel-diode operation and the negative-resistance property exhibited by the tunnel diode was discussed in NEETS, Module 7, Introduction to Solid-State Devices and Power Supplies, Chapter 3. Figure 2-39.—Tunnel-diode characteristic curve. TUNNEL-DIODE OSCILLATORS.—A tunnel diode, biased at the center point of the negative- resistance range (point B in figure 2-39) and coupled to a tuned circuit or cavity, produces a very stable oscillator. The oscillation frequency is the same as the tuned circuit or cavity frequency. Microwave tunnel-diode oscillators are useful in applications that require microwatts or, at most, a few milliwatts of power, such as local oscillators for microwave superheterodyne receivers. Tunnel-diode oscillators can be mechanically or electronically tuned over frequency ranges of about one octave and have a top-end frequency limit of approximately 10 gigahertz. Tunnel-diode oscillators that are designed to operate at microwave frequencies generally use some form of transmission line as a tuned circuit. Suitable tuned circuits can be built from coaxial lines, transmission lines, and waveguides. An example of a highly stable tunnel-diode oscillator is shown in figure 2-40. A tunnel-diode is loosely coupled to a high-Q tunable cavity. Loose coupling is achieved by using a short, antenna feed probe placed off-center in the cavity. Loose coupling is used to increase the stability of the oscillations and the output power over a wider bandwidth.


Electrical News
TV Reboots with Web-Like Service
The next-generation U.S. standard for terrestrial TV will embrace Web...
eetimes.com
MWC Wrap-Up: 15 Curious Things We Spotted
The Mobile World Congress has literally morphed into the Everything...
eetimes.com
Shifting Mindsets: Static Verification Transforms SoC Design at RT Level
Teams 'shift left' to tackle challenges earlier in the design...
eetimes.com
TechInsights: Overcoming Smart Glasses' Performance Challenges
Power may be the key to success in smart glasses...
eetimes.com
Friday Quiz: More Spectrum and Network Measurements
Robert Witte's book "Spectrum and Network Measurements" provides us with...
eetimes.com
Smartphone, Samsung in Trouble
With its Galaxy S6 announcement at MWC, Samsung and smartphones...
eetimes.com
Wireless Links to Provide Automation & Enhanced Efficiency in Medical Apps
Using FPRF devices, manufacturers can add a cost-effective enhancement to...
eetimes.com
Full-featured power system manager with accurate input current and energy metering
The LTC2975 is a four-channel PMBus Power System Manager with...
eetimes.com
Musings With Regard To Being a One-Armed Engineer
Have you ever considered how difficult it would be to...
eetimes.com
Versatile Comparators enable fast signal detection, level translation and clock recovery
In this video, a new high speed CMOS output comparator...
eetimes.com
VR is New Reality at GDC
Oculus, Sony, Google and an open source project showed virtual...
eetimes.com
IBM's Watson Does Deep-Learning Too
IBM Corp. recently acquired AlchemyAPI for its "deep learning" capabilities,...
eetimes.com
EEVblog #721 – Globalstar Satellite Phone Teardown
What’s inside a 2000 vintage Globalstar GSP1600 Tri-Band Satellite Phone?...
eevblog.com
Intel Calls for 3D IC
Intel is right: heterogeneous integration enabled by 3D IC "increasingly...
eetimes.com
Engineers Can Solve Great Problems
Today's engineering students get to see what it's like to...
eetimes.com
Qualcomm CTO on LTE-U, 5G Challenges
EE Times caught up with Matt Grob, Qualcomm CTO. We...
eetimes.com
Low-Power Wireless MCUs Proliferate
Wireless device developers now have a new range of RF...
eetimes.com
Engineers on Creating Better Technical Documentation
Everyone benefits from good documentation. So why does so much...
eetimes.com
ESC Boston 2015 Sneak Peek -- Awesome Analog Meters
In this Fantastical Theatre presentation at ESC Boston 2015, Max...
eetimes.com
2D Material Beats Graphene
Black Phosphor is a 2D material with advantages over graphene,...
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 +