TPA3250 somebody is listening?

I got a pair of LME49720 chips today. How do I tell the direction they go in? There is the printing on the top of the chip and the half-circle notch out of the left side. Do I put them in with the writing going the same direction as the stock chips? There is not a mark on the first leg as some pictures show (and others do not).

yes...as discribed above, half circle notch or a dot at the left corner = leg 1

8 7 6 5
)
1 2 3 4

the legs of the new chips are going little outside. so bind it carefully together that it fits better into the socket.

have fun for burn in ...and better SQ
 
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tpa3250 can be used with psu up to 38V
tpa3255 can be used with psu up to 53.5V (even 56.5V for easy loads)
lm2596 can be used with inputvoltage up to 40V
lm2596hv can be used with inputvoltage up to 60V, hv=high voltage.
(TI hasn't produced the 2596hv I think, so production stopped when TI bought National Semi in 2011)(clones/fakes :D)
 
tpa3250 can be used with psu up to 38V
tpa3255 can be used with psu up to 53.5V (even 56.5V for easy loads)
lm2596 can be used with inputvoltage up to 40V
lm2596hv can be used with inputvoltage up to 60V, hv=high voltage.
(TI hasn't produced the 2596hv I think, so production stopped when TI bought National Semi in 2011)(clones/fakes :D)

Aaah.. you are an expert....thank you !,,,,now i can mentoined what you mean:D
actually i use the original psu and and will try not more then about 30V-32V because of caps.

chris
 
Does the ceramic resistorhousing make outside enclosure feel warmer ?

i have just a smal room with smal speakers and actually i play some more punchy music..........zhu....gogo penguin...

but i think i psuh the amps not so hard.

yesteday i forgott to low down the level at tidal and i played "a hundred moons" by gogopenguin, tidal level nearly max = 92 and the fx502s was set about 12 o clock --> at second 11 of the title the amp shut down on the left channel and push down the right channel -->with error led blinking. after switch off and 5 seconds wait it works again.

yes i can feel the difference slightly.
 
my room is under my terrace a exra living room.
4x6 m but just 2,25cm high. speakers are 2,90m from listening position . and about 1,2m from the back wall. behind my sofa is 1,7m

now artist boomshakkalakka - title "warum"....sorry its german...but..... no problem ...no switch off.... :rofl::cool::D
 
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Shut down doesn't have to be thermal, although pcb=heatsink looks very narrow, but TI's first versions of EVM boards also had too early shutdown of one channel, that was voltage related I think. Ground causing voltage differences, because of high frequency high current in that groundplane.

Getting chip above 150 degrees Celsius with 24 volt PSU and music as source, I think that is very hard if not impossible.
 
Shut down doesn't have to be thermal, although pcb=heatsink looks very narrow, but TI's first versions of EVM boards also had too early shutdown of one channel, that was voltage related I think. Ground causing voltage differences, because of high frequency high current in that groundplane.

Getting chip above 150 degrees Celsius with 24 volt PSU and music as source, I think that is very hard if not impossible.

yes i understand you...you are right the psu is not as strong..... gets undervoltage..i guess...next step is to mod / check the psu.
i have some 15V 16A power psu-RC car psu......, but then i get the problem with not regulated LM317, as i get reminded previous pages before.

thx
 
I have a question about power used. The FX502SPRO is quite powerful for my high-efficiency speakers, so in order to have a usable volume range, I turn down the output of my Chromecast so that I can use more range on the FX502SPRO's volume knob.

2 questions = does that mean that the amp is using more power? Does it mean the 3250 chip will generate more heat?

I don't know if the answer is yes to both of those or if the chip is at the same power and the volume pot is just cutting the output.
 
I have a question about power used. The FX502SPRO is quite powerful for my high-efficiency speakers, so in order to have a usable volume range, I turn down the output of my Chromecast so that I can use more range on the FX502SPRO's volume knob.

2 questions = does that mean that the amp is using more power? Does it mean the 3250 chip will generate more heat?

I don't know if the answer is yes to both of those or if the chip is at the same power and the volume pot is just cutting the output.

hi swank42

i think you are too afraid about the heat of this amp. general this chip has a thermal and OVC (over current protection) circuit implemented! so dont worry.;)

the amps job is to amplifie the level of his input to a regulated (volume knob) gain. depending of the voltage of psu and the max technical requiremnt of this amp you get more or less the possible "power" - if the psu keeps stable.


the position of the volume knob or your volume level of the amps input is not releated to the power. it should give you a wider range for adjust your needed volume during playing music.
youknow. the volume knob of the fx502spro is very sensitive, that means little movement of this knob is generating a big step louder.


clear?:D;)
 
i have just a smal room with smal speakers and actually i play some more punchy music..........zhu....gogo penguin...

but i think i psuh the amps not so hard.

yesteday i forgott to low down the level at tidal and i played "a hundred moons" by gogopenguin, tidal level nearly max = 92 and the fx502s was set about 12 o clock --> at second 11 of the title the amp shut down on the left channel and push down the right channel -->with error led blinking. after switch off and 5 seconds wait it works again.

yes i can feel the difference slightly.

happend again - amp 2 BB2134 but exactly some as obave discribed
but other channel shut down = right channel

switch of ...3 sec waiting.....and go ahead :D:D:D with volume 83 volume at tidal... !


nice afternoon...
 
..psu check...

Hi

i used the "stronger" (current max 16A). its a psu with 15V:
corally 250Watt psu
corally netzteil 250W - Google Search

my impression is that this psu really give me exact the same volume of music and a sound with more "darkness". the disadvantage of this psu is that the fan is real loud. so i have to play tiltes with more action:)

i tryed to push the amp as hard as described before. the amp is not switching of --> so the previous shut down was a weakness of the original psu.


 
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...smsps measurements...

Good morning

yesterday i checked this RC smps shortly. recommended 15V /16Amax

my loadbox has 3x4,2 Ohm /100W resistors = 1,4 Ohms overall resistor.:)

10,53 Ampere at 14,74Volt is fine. no noise measurements with scope.

the fan is very loud.:rolleyes:
 

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