Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Class AB power dissipation?

Status
Not open for further replies.

wat007

Junior Member level 3
Joined
Apr 28, 2009
Messages
27
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,283
Activity points
1,455
Hello All,

How can I calculate the power dissipation of a class AB audio amplifier?
Any idea or reference will be a great help.


Regards

monix
 

Look at the datasheet of one of the many class-AB IC power amplifiers like the LM3886:
1) When its output is almost at clipping driving 50W into 8 ohms with a plus and minus 35V supply, it dissipates 31W.
2) When the output is 30W into 8 ohms and everything else is the same as above then it dissipates 34W (its max dissipation).
3) When it is idling without a signal with a plus and minus 35v supply, its current is typically 50mA then it dissipates 2.8W.

With a 4 ohm load its output power and dissipation are more.
 

Another factor is the peak to average ratio. TI once had a program to calculate the dissipation with different types of music.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top