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I changed mine to 100u in the B40s and even reduced the input 1uf as we
response below 300hz. I calculated the time constant from the roll off
freq and worked
out the cap.
In bridge mode you get double the power! I had originally recommended
bridge to Farhan.
At 02-03-2018, you wrote:
I think you're right.
The output pin has a quiescent DC voltage of around half the supply
voltage, or about 6v,
so the 470uF cap will have a 6v charge on it when operating. A
significant bit of energy
for the TDA2822 to provide, and it tries to do so almost instantaneously
in the case of a short.
A series resistor seems prudent.
Perhaps the 470uF cap could be reduced to 100uF.
At 500hz the 100uF would have an impedance of 1/(2*pi*500*100e-6) = 3.18
which seems borderline for good sound quality when using an 8 ohm
I vote for the resistor. Something like 4 or 8 ohms, 1/2 Watt.
But worth experimenting if somebody has a stash of cheap TDA2822's on
Configuring the TDA2822 for Dex's bridge configuration does away
with the cap charging problem,
but now the headphone jack has to be floating. The bridge would be
ideal for an internal speaker.
On Thu, Mar 1, 2018 at 11:47 am, Jim Sheldon wrote:
- My take is that huge 470 uF electrolytic in the output of the
TDA2822M and the speaker gets a huge surge at turn on and during any loud
noise or POP in the audio chain.