Re: U1 fried

Allard PE1NWL
 

NJM2073D seems to be a replacement for TDA2822, price is about one dollar:

http://mklec.com/components/integrated-circuit/op-amps/jrc-njm2073d-stereo-audio-power-amplifier

73 Allard PE1NWL

On Thu, March 1, 2018 01:45, Jerry Gaffke via Groups.Io wrote:
Ah, the TDA82822D part in the SOIC8 package is a good find.
Feeling much better now!

Digikey has it for a bit over a dollar (Mouser says a minimum buy of
2000).
Maybe hfsignals will move to the more easily gotten SMD part if they ever
roll the board.
Though I'm pretty sure I could solder the SMD into place with just some
short wires,
not bothering with the adapter board.

The chip is rated to work with a 4Ω load so a 4Ω resistor should do. I
doubt the chip would blow so fast that FB fuse wouldn’t protect it.
Yes, I think a 4 ohm resistor would probably do, I was getting rather
cautious when I saw how hard the M part was to obtain.
I'm suspicious that with a 12v supply it is close to the edge, they seem
to blow with little provocation.
Most of the datasheet seems to assume a max of 9v.
The fact that it works down to 1.8v reinforces this notion.

The fuse might protect it, depends on the failure mode.
The fuse costs about as much as the TDA2822D.

Jerry

On Wed, Feb 28, 2018 at 04:02 pm, Clark Martin wrote:


The TDA2822D in effect replaces the “M� version.  It appears the
same
except it’s an SMD part.  You can get SMD to through hole adapter
boards
that would let you use one with the µBitX.  It would likely be cheaper
than buying the “M� version.
 
 

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