Overheated 6 Watt 2 Channel Power Amplifier IC CD4440
A customer brought in this 5C Amp999 Stereo Amplifier for me to repair and the complaint was no sound output. This stereo amplifier can be turned On but no sound at all.
I connected the speakers at the output of the amplifier to double confirm it and indeed it was totally no sound.
I opened the cover and saw a linear transformer, USB Kit and the main pcb-see the photo below:
I focused on the main PCB because this is the heart of the amplifier.
From visual inspection, it seems that all the components were good and the wires connectors were also intact.
However, there was only one problem that cannot be detected with visual inspection and the problem was overheated IC. I touched both the power amplifier ICs ( CD4440) and both were so hot.
I took out the overheated ICs and replaced with another part number and brand which were the Sanyo LA4440 IC -see the photo below:
You can view the IC datasheet by clicking on the photo below:
Once the new ICs were fitted and powered On, the sound came back and I was delighted
Conclusion- Assuming after the replacement of the ICs and still no sound, then I have to check on all the nearby or corresponding components since the DC supply voltage to both the ICs were within range. If you want to learn how to accurately check electronics components, you can get Jestine Yong’s ebook here-fully recommended.
This article was prepared for you by Suranga Bandara who owns an Electronics repair shop in Anuradapura, Sri Lanka.
Please give a support by clicking on the social buttons below. Your feedback on the post is welcome. Please leave it in the comments. If you have electronic repair articles to share with us, please contact us HERE.
P.S- If you enjoyed reading the above article, click here to subscribe to my blog (free subscription). That way, you’ll never miss a post. You can also forward this website link to your friends and colleagues-thanks!
Note: You may check out previous post about fixing active speaker in the below link:
https://www.electronicsrepairfaq.com/tactical-switch-problem-in-fan-control-board
About admin
Jestine Yong works as an Electronics Repair Lecturer in Kuala Lumpur Malaysia and his training website is http://www.NoahtechElectronicsTraining.com. You can check out his repair blog at http://www.JestineYong.com
8 comments on “Overheated 6 Watt 2 Channel Power Amplifier IC CD4440”
Leave a Reply
Leave a Reply
This site uses Akismet to reduce spam. Learn how your comment data is processed.
Excellent an-expert-easy fix!
Pro repair with always interesting datasheet Mr. suranga! I do hope that the customer’s loudspeakers have survived blowing up both 6 Watt 2 Channel Power Amplifier CD4440 IC’s. Which also may happen again if they were the wrong impedance.
You are right Albert when it comes to wrong impedance of the loudspeakers.
Anyway, I’ve enjoyed reading this article of Suranga.
Good job, Suranga.
Great job I really enjoy your articles.
What an insightful repair article. Thank you so much Mr Suranga Bandara,keep it up.
Thanks for helping
Hi Engineers,
My Phillips AZ2100/12 bought in 1998 is not sounding. Only low sound at MW radio through headphone.
1.No sound in cassette player.
2. No sound in FM/AM
I have consulted nearby repair shops and even Phillips service center but all refused by saying parts may not available.
Please advice to fix problem.