Quantcast AMPLIFIER CLASSES OF OPERATION - 14180_18

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
1-6 You might hear that a vacuum tube is a voltage-operated device (since the grid does not need to draw current) while the transistor is a current-operated device. You might agree with this statement, but both the vacuum tube and the transistor are still current-control devices. The whole secret to understanding amplifiers is to remember that fact. Current control is the name of the game. Once current is controlled you can use it to give you a voltage gain or a power gain. This chapter will use transistor amplifiers to present the concepts and principles of amplifiers. These concepts apply to vacuum-tube amplifiers and, in most cases, magnetic amplifiers as well as transistor amplifiers. If you wish to study the vacuum-tube equivalent circuits of the transistor circuits presented, an excellent source is the EIMB, NAVSEA 0967-LP-000-0120, Electronics Circuits. The first amplifier concept that is discussed is the "class of operation" of an amplifier. AMPLIFIER CLASSES OF OPERATION The class of operation of an amplifier is determined by the amount of time (in relation to the input signal) that current flows in the output circuit. This is a function of the operating point of the amplifying device. The operating point of the amplifying device is determined by the bias applied to the device. There are four classes of operation for an amplifier. These are: A, AB, B and C. Each class of operation has certain uses and characteristics. No one class of operation is "better" than any other class. The selection of the "best" class of operation is determined by the use of the amplifying circuit. The best class of operation for a phonograph is not the best class for a radio transmitter. Class A Operation A simple transistor amplifier that is operated class A is shown in figure 1-4. Since the output signal is a 100% (or 360º) copy of the input signal, current in the output circuit must flow for 100% of the input signal time. This is the definition of a class A amplifier. Amplifier current flows for 100% of the input signal. Figure 1-4.—A simple class A transistor amplifier. The class A amplifier has the characteristics of good FIDELITY and low EFFICIENCY. Fidelity means that the output signal is just like the input signal in all respects except amplitude. It has the same


Electrical News
Google Preps Virtual Network
Google described Andromeda, a central server-based controller users will be...
eetimes.com
EEVblog #656 – Pacemaker Monitor Teardown
What’s inside a dial-in pacemaker monitor system? Datasheets: LMV824 MAX4330...
eevblog.com
Getting Your First Sales Pick Right
A company needs to create a repeatable sales process to...
eetimes.com
The People Who Created Our Jobs
Without the likes of Ohm, Faraday, Henry, and many others,...
eetimes.com
Mobile Engineering: 10 Cheap, Mostly Android Apps
Whether Android- or Apple-based, your mobile phone can be an...
eetimes.com
Brazil's Path to Hardware Manufacturing at Home
John Hall, president of the Linux Foundation, lays out a...
eetimes.com
Fairchild to Close 2 Manufacturing Facilities
Fairchild is eliminating its internal 5-in wafer fabrication lines and...
eetimes.com
JEDEC Unveils Low-Power Memory Standard
JEDEC published its LPDDR4 specification, which, with a redesigned architecture,...
eetimes.com
SanDisk Bullish on SSD Adoption
Ultra II is aimed at consumers looking to upgrade HDD...
eetimes.com
Live Chat Wednesday, Aug. 27: Is iPhone Relevant?
Join industry analysts and EE Times editors for a live...
eetimes.com
Live Chat Wednesday, Aug. 27: Is iPhone Relevant?
Join industry analysts and EE Times editors for a live...
eetimes.com
Digital Light Projectors Downsize & Diversify
Digital light projectors (DLPs) were used in the first and...
eetimes.com
Memory Design Articles: DDR4, LRDIMMs, MBIST, Embedded Flash
A roundup and summary of memory design articles across the...
eetimes.com
IoT Needs Open Discovery Scheme
The Internet of Things will require an open-source self-classification scheme...
eetimes.com
US Launches Smart Cities Effort
The US has launched a challenge to municipal governments around...
eetimes.com
Bitcoin Bill Begs Questions
A California law passed in late June attempted to legalize...
eetimes.com
Breadboard for Lunch, Conclusion
In the conclusion, you'll see why there's a difference between...
eetimes.com
Intel Shrinks 3G Chip for IoT
Intel's latest modem for the mobile Internet of Things, the...
eetimes.com
Google Glass & Lookalikes Find Niches
Google Glass, Recon Jet, and Epson Moverio have been solutions...
eetimes.com
Murata to Buy RF IC Vendor Peregrine for $471M
Passive component powerhouse, Japan's Murata Manufacturing Co. Ltd., has taken...
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 +