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TDA2822 ill treatment test! Photo of blown TDA

DrZ <zehrhj2@...>
 

Here is what mine looks like - it's the one that came in the Bitx - Howard

Michael Hagen
 

Needs some Crazy Glue!!


On 3/2/2018 6:16 AM, DrZ wrote:
Here is what mine looks like - it's the one that came in the Bitx - Howard

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...

Michael Aiello
 

Mine failed immediately after apply power to the board after wiring up the power connector. Nothing else was connected. There was a loud crack, and a puff of magic smoke, then silence.
Photos  of failed chip look similar.
I think the chip may have been already replaced once on the board before I got it - see the soldering of the chip pins vs. the soldering ot the other surrounding connections. Looks like it was manually soldered to me. These photos were taken before I replaced the bad chip with a socket, but after the failure happen.
Probably one or more bad chips involved, the replacement in the socket has been completely well behaved.

73
Mike N2HTT

Jerry Gaffke
 

So two reports of "WX" TDA2822M's going up in smoke.
I'm very very curious if all blown chips turn out to be WX branded,
and none are FCI.
 
There is a website for  WX:  http://www.wx-ic.com/Cn/Product_Detail_Images.aspx?id=105303&UserInfo_ID=216432&CorpProductImages_ID=106897
though I can't find a datasheet.
Probably a 3'rd tier clone manufacturer.

May need either a chip from a "good" manufacturer whoever that might be,
or a regulator to make it a max of 6v or so into the TDA2822.

Jerry, KE7ER



On Fri, Mar 2, 2018 at 06:59 am, Michael Aiello wrote:
Mine failed immediately after apply power to the board after wiring up the power connector. Nothing else was connected. There was a loud crack, and a puff of magic smoke, then silence.

Rick Price
 

The one that went up in smoke yesterday in my brother-in-laws was a WX make
and has the same numbers on it like the picture in msg#43297. Mine is also a
WX make, has the same numbers, but has not given me a problem as yet, and
runs cool. I put the 4 ohm resistor in the speaker line and also put a 12V
regulator on the red receiver power wire. No problems with mine yet.

Rick
KN4AIE

John
 

Mine didn't look as bad but it also blew my 2A fuse.

Jason Schlager
 

Have the same chip on mine. Worried about powering it up now.
--
Jason Schlager
KM6AUS

Jacob Farnes
 

Finally got mine on the bench. Just wired up audio pot, encoder with button, tip & sleeve of 1 heaphone jack, power, and Antenna. 

Used my N2CQR-designed 160m-capable HPF with the original ceramic caps to knock out the AM stations. (Now to dig out the Silver Micas from the Christmas trip).

Plugged in a 8-ohm Realistic communication speaker with a TS plug. Nice and loud so far. Just wish I could find some SSB Amateur Radio stations. Heard various usual shortwave on 5085 but not WWV at 5. Heard WWV at 2.5 but wasn't quite right with the carrier bleeding through.

So far RX hasn't been trouble with this WX TDA2822M. So far... I'll report back to this thread if that changes.

Jacob Farnes
 

Forgot another important detail: powered by battery measuring 12.6V under load.

Vince Vielhaber
 

160 has some kind of contest going on as well as a number of QSOs. 75 is quite busy. Should be able to find traffic on either of those bands.

Vince.

On 03/03/2018 12:13 AM, Jacob Farnes via Groups.Io wrote:
Finally got mine on the bench. Just wired up audio pot, encoder with
button, tip & sleeve of 1 heaphone jack, power, and Antenna.

Used my N2CQR-designed 160m-capable HPF with the original ceramic caps
to knock out the AM stations. (Now to dig out the Silver Micas from the
Christmas trip).

Plugged in a 8-ohm Realistic communication speaker with a TS plug. Nice
and loud so far. Just wish I could find some SSB Amateur Radio stations.
Heard various usual shortwave on 5085 but not WWV at 5. Heard WWV at 2.5
but wasn't quite right with the carrier bleeding through.

So far RX hasn't been trouble with this WX TDA2822M. So far... I'll
report back to this thread if that changes.

Lawrence Galea
 

Dedicated to the TDA2282Ms who have given up the ghost with a puff of smoke

Puff The Magic Dragon -- Peter, Paul & Mary ~ Live 1965 

Seriously since the maximum supply for the TDA 2281M is 12V and absolute maximum is 15 volts, I suggest that a lower supply be used such as using a 7806 or 7805 regulator to supply the TDA. I had previously suggested a 7808 or 7809 but a 7806 or 7805 will be better.
The Data sheet also states that "Absolute maximum ratings are stress ratings only and functional device operation is not implied. The device could be damaged beyond Absolute maximum ratings."
The Data sheet suggests a 4Ω speaker for supply voltages between 3  and 6 volts single ended amplifier with an 8Ω speaker if using the two amplifiers in the IC as a bridge.
It is to be noted that the Data sheet measurements are made using 3 and 6V and NOT 12V.
Remember that as someone else had said, a component will sacrifice itself to protect the fuse (or something to this effect)
Regards
Lawrence


On Fri, Mar 2, 2018 at 3:16 PM, DrZ <zehrhj2@...> wrote:
Here is what mine looks like - it's the one that came in the Bitx - Howard


Tim Gorman
 

Has anyone tried one of those adhesive heatsinks made for the Raspberry
Pi ic's? Is this a long-term heat problem the heatsink might help. It
certainly won't if it is from charging current into the series
capacitor in the output.

tim ab0wr

On Sat, 3 Mar 2018 16:34:06 +0100
"Lawrence Galea" <9h1avlaw@...> wrote:

Dedicated to the TDA2282Ms who have given up the ghost with a puff of
smoke

https://www.youtube.com/watch?v=z15pxWUXvLY
Puff The Magic Dragon -- Peter, Paul & Mary ~ Live 1965

Seriously since the maximum supply for the TDA 2281M is 12V and
absolute maximum is 15 volts, I suggest that a lower supply be used
such as using a 7806 or 7805 regulator to supply the TDA. I had
previously suggested a 7808 or 7809 but a 7806 or 7805 will be better.
The Data sheet also states that "Absolute maximum ratings are stress
ratings only and functional device operation is not implied. The
device could be damaged beyond Absolute maximum ratings."
The Data sheet suggests a 4Ω speaker for supply voltages between 3
and 6 volts single ended amplifier with an 8Ω speaker if using the
two amplifiers in the IC as a bridge.
It is to be noted that the Data sheet measurements are made using 3
and 6V and NOT 12V.
Remember that as someone else had said, a component will sacrifice
itself to protect the fuse (or something to this effect)
Regards
Lawrence


On Fri, Mar 2, 2018 at 3:16 PM, DrZ <zehrhj2@...> wrote:

Here is what mine looks like - it's the one that came in the Bitx -
Howard


Arvo W0VRA
 

The subsequent frying of the resistor on pin 6 suggests a catastrophic failure within the chip that's way beyond a thermal management problem. The chip should be replaced.

Jerry Gaffke
 

Many of the datasheets I see give a max operating voltage of 15v, including the original ST part
and the FCI part.  No uBitx with the FCI part has failed, only the WX part. 
All datasheets say 15v Absolute Max (above which damage may occur).

There is no WX datasheet on the web.
Two posts here describe previous experience with some unknown make of TDA2822 clones
that can fail at supply voltages above 7 or 8 volts.
That may well apply to the WX part.
First thing I would do if I had the WX part is order a better part.
I don't know of any FCI parts that have smoked, even when abused with a short to ground.

That datasheet table with speaker impedances shows the maximum supply voltage at
which less than 10% distortion will be experienced for the specified output power.
It does not show when damage to the part will occur.

The datasheet says damage will occur if the Absolute Max supply voltage of 15v is exceeded,
or the output current exceeds 1 Amp, or the device power dissipation exceeds 1 Watt.
With a 12v supply, you might exceed the max current or power dissipation if you crank up
the volume too high with a low load impedance, but otherwise 12v should not damage the device. 
According to the datasheet. 

Reducing the supply voltage to 5v would pretty much eliminate these risks,
and an extremely good idea if you wish to keep the WX part.
First step is to cut the short trace on the back of the board into the square pad of C76 (near X2).
Then add an LM7805 regulator, pin 3 goes to that square pad of C76,  pin 1 goes to
the feedthrough at the other end of the cut trace, pin 2 goes to ground.
Ideally, add a 0.33uF (or anything from 0.1 to 10uF) cap from pin 1 to ground.
Maybe glue the LM7805 face down onto the back of the board, the leads in the vicinity of C76.

Jerry



.

The only TDA2822's that have blown that I am aware of were marked "WX", not "FCI".



On Sat, Mar 3, 2018 at 07:34 am, Lawrence Galea wrote:
Seriously since the maximum supply for the TDA 2281M is 12V and absolute maximum is 15 volts, I suggest that a lower supply be used such as using a 7806 or 7805 regulator to supply the TDA. I had previously suggested a 7808 or 7809 but a 7806 or 7805 will be better.
The Data sheet also states that "Absolute maximum ratings are stress ratings only and functional device operation is not implied. The device could be damaged beyond Absolute maximum ratings."
The Data sheet suggests a 4Ω speaker for supply voltages between 3  and 6 volts single ended amplifier with an 8Ω speaker if using the two amplifiers in the IC as a bridge.
It is to be noted that the Data sheet measurements are made using 3 and 6V and NOT 12V.
Remember that as someone else had said, a component will sacrifice itself to protect the fuse (or something to this effect)
Regards
Lawrence
 

Mike Woods
 

I have continued to update the news story about the TDA2822 woes on http://ubitx.net

Go to the article directly here: http://ubitx.net/2018/03/01/tda2822-problems/

Hopefully it reflects the state of play on what we know about failure modes for the TDA2822, and how to address these problems.

It would be good to know if anybody tries Jerry's 5v mod below and how much it reduces audio output (if at all).

73 Mike ZL1AXG

On 4/03/18 10:37 AM, Jerry Gaffke via Groups.Io wrote:

Reducing the supply voltage to 5v would pretty much eliminate these risks,
and an extremely good idea if you wish to keep the WX part.
First step is to cut the short trace on the back of the board into the square pad of C76 (near X2).
Then add an LM7805 regulator, pin 3 goes to that square pad of C76,  pin 1 goes to
the feedthrough at the other end of the cut trace, pin 2 goes to ground.
Ideally, add a 0.33uF (or anything from 0.1 to 10uF) cap from pin 1 to ground.
Maybe glue the LM7805 face down onto the back of the board, the leads in the vicinity of C76.
--
Mike Woods
mhwoods@...

Jerry Gaffke
 

I haven't tried it yet.
Would expect the gain to be the same, but distort a bit sooner at the highest volume settings.


On Sat, Mar 3, 2018 at 02:18 pm, Mike Woods wrote:
It would be good to know if anybody tries Jerry's 5v mod below and how much it reduces audio output (if at all).

John
 

Bought some TDA2822L's on eBay, seller seemed to be Tayda. Even after a few hours, no heat whatsoever without hardware changes.

John

Jerry Gaffke
 

Keep us posted on how this works out.
Tayda sells several versions of the TDA2822.
Can you tell us what is printed on the parts you have?
My guess is that they are made by UTC in Taiwan:
  https://www.taydaelectronics.com/datasheets/A-1002.pdf
The "L" in the part number just means it is lead free.

Jerry


On Sun, Mar 4, 2018 at 07:18 pm, John wrote:
Bought some TDA2822L's on eBay, seller seemed to be Tayda. Even after a few hours, no heat whatsoever without hardware changes.

ohwenzelph
 

Has no one tried changing the TDA2822 to the “bridge” configuration?

Wired to tip and ring there would be no ground connection and it would work with stereo or mono plug. ( I guess the phasing might be messed up with the sereo phones for voice)

John
 

On Mon, Mar 5, 2018 at 03:16 am, ohwenzelph wrote:
Has no one tried changing the TDA2822 to the “bridge” configuration?

Wired to tip and ring there would be no ground connection and it would work with stereo or mono plug. ( I guess the phasing might be messed up with the sereo phones for voice)

 This is my replacement TDA2822L ordered through eBay. In the package was a folder from Tayda.