Amplifier, function of BT 4840 IC ?

Papabravo

Joined Feb 24, 2006
21,256
Who can know the function of BT 4840 IC by the company Boomtech 1008s of an audio ic for A335
Any chip where "alldatasheet" comes up as the #1 hit is probably past EOL, no longer in production, and obsolete. You can only know the function of such a chip if you can get your hands on a complete datasheet. Without a complete datasheet there will always be holes in that understanding.
 

MisterBill2

Joined Jan 23, 2018
18,928
Any chip where "alldatasheet" comes up as the #1 hit is probably past EOL, no longer in production, and obsolete. You can only know the function of such a chip if you can get your hands on a complete datasheet. Without a complete datasheet there will always be holes in that understanding.
PB is correct, BUT if you can get a copy of the circuit that the IC is in you should be able to understand the function that it provides.
If it is in a product produced by a company called "BOOMTECH" it is probably an audio amplifier, either a power amplifier or a lower level stage audio amplifier.
If you can tell us what sort of system the IC is in, then we can provide more assistance, possibly.

If the need is to repair something then the problem is quite different.
 

Thread Starter

Ugenya

Joined Mar 17, 2024
4
PB is correct, BUT if you can get a copy of the circuit that the IC is in you should be able to understand the function that it provides.
If it is in a product produced by a company called "BOOMTECH" it is probably an audio amplifier, either a power amplifier or a lower level stage audio amplifier.
If you can tell us what sort of system the IC is in, then we can provide more assistance, possibly.

If the need is to repair something then the problem is quite different.
This BT 4840 IC its used in connection with TL 074C amplifier to output bass, stereo system in a system known as CREATIVE A335..around 2010...low output channel in bass and one speaker help please
 

MisterBill2

Joined Jan 23, 2018
18,928
OK, so now we know that the goal is to repair an amplifier or perhaps a complete receiver. That means that the need is to understand enough to diagnose the prob so that a repair can be done in a reasonable manner. So now a few questions. First, does the thread starter have a multimeter to be able to check voltages in the unit needing repair, and then, can the TS follow a circuit schematic and relate that to the actual equipment being diagnosed. And then the third question, is the TS able to unsolder and replace a failed component? These are the basic skills and resources needed to complete a successful repair on an electronic device of almost any kind.
What I found today: The BT4840 parts are Monolithic CMOS True Color, a member of the BT484 family manufactured by BOOMTECH are available for purchase at Jotrin Electronics. So they do appear to be available even if they are out of production.

The prices that I saw are interesting: ob ebay $38 for two of them in used condition., elsewhere prices from $6.60 to about $7.75. Clearly ebay, as is often the case, is way overpriced.

BUT now it is identified as a stereo power amplifier in a ZIP19 package.
NEXT, the TS stated that the volume was low on one channel. The monolithic power amplifiers usually fail totally on one channel, or burn out completely. CERTAINLY unsoldering that IC and installing a replacement is not a task for a beginner at all. It will be quite a project for an excellent technician with all the correct tools and equipment.
AND maybe the problem is someplace else in the device. This is where following a circuit schematic and using a meter come into play. Does the TS have those skills and some equipment???
 
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Papabravo

Joined Feb 24, 2006
21,256
Just because a chip is no longer in production does not mean that it is unobtainable. There is a gray market for obsolete parts that will disgorge any remaining supply of parts in the hands of speculators.
 

Thread Starter

Ugenya

Joined Mar 17, 2024
4
OK, so now we know that the goal is to repair an amplifier or perhaps a complete receiver. That means that the need is to understand enough to diagnose the prob so that a repair can be done in a reasonable manner. So now a few questions. First, does the thread starter have a multimeter to be able to check voltages in the unit needing repair, and then, can the TS follow a circuit schematic and relate that to the actual equipment being diagnosed. And then the third question, is the TS able to unsolder and replace a failed component? These are the basic skills and resources needed to complete a successful repair on an electronic device of almost any kind.
Actually l have a basic in soldering parts and a bit of electronic components..most of the amplifier circuits are the big problem how resistors and capacitors are used more than usual..how the tl 074 ic amp is used to output through BT 4840 ic
 

Thread Starter

Ugenya

Joined Mar 17, 2024
4
Actually l have a basic in soldering parts and a bit of electronic components..most of the amplifier circuits are the big problem how resistors and capacitors are used more than usual..how the tl 074 ic amp is used to output through BT 4840 ic
Datasheet l can work on very nicely....since of the electronic schematic diagrams l am well conversant with sir
 

MisterBill2

Joined Jan 23, 2018
18,928
What I found today Is a Source of the part at a reasonable price. And I am glad that the TS is able to do electronic soldering. I commented because I have seen examples of soldering efforts that resulted in circuit boards not being repairable at all. That was other people, elsewhere. So I had to ask.
And now, once again, it may be a different portion of the system that is not functioning correctly. THAT is where the diagnostic effoert will need to be, to see where the problem actually is located.
 
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