Hi to all! I've build a Power amp based on the TDA7250 that i think is a good amp and economic amp!
I use a SMPS as Power Supply. From +14 to +/-42V@2.2A that i think should be enough for this amp.
OR not?
My problem is that i don't ear no sound from it.. what should be? I know that maybe a mistake on soldering but
What are the main things to check...?
As Q1 and Q2 i've used TIP142/147 that should be enough to have 70W+
Thanx in advance for all the suggest and to all the ppl that will give an answer...
I use a SMPS as Power Supply. From +14 to +/-42V@2.2A that i think should be enough for this amp.
OR not?
My problem is that i don't ear no sound from it.. what should be? I know that maybe a mistake on soldering but
What are the main things to check...?
As Q1 and Q2 i've used TIP142/147 that should be enough to have 70W+
An externally hosted image should be here but it was not working when we last tested it.
Thanx in advance for all the suggest and to all the ppl that will give an answer...
I have no clue what the problem is, but next time, please don't post the same question in 3 different forums.
Firstly, as I'm sure you're aware...you only need to post this in one forum. Since the heart of this circuit is an IC, it should go in either the Car Audio or Chip Amps forums. If it is for a car then you have a choice - otherwise it should be in the Chip Amps. People will answer you if they want to and spam won't change that.
Assuming that all is soldered correctly (check for dry solder joints) then you should check pinouts (especially for short circuits at input signal, power supply and output signal.
Have you measured the voltage in the power supply at the pins of the chip?
Gaz
Assuming that all is soldered correctly (check for dry solder joints) then you should check pinouts (especially for short circuits at input signal, power supply and output signal.
Have you measured the voltage in the power supply at the pins of the chip?
Gaz
Pretty complicated for first amp... you should stick with something like the LM3886...that was my first high power amp. After I figured out it needs a split supply and not a single, it worked the first time. www.national.com
TDA7250 - nice chip
Hi MaXiZ
Nothing wrong with chip. The schematic you showed is not meant for TIP142/147.
You can find some info here:
schematics
TDA7250 Amp
TDA7250 in Pro Use
Cheers
Hi MaXiZ
Nothing wrong with chip. The schematic you showed is not meant for TIP142/147.
You can find some info here:
schematics
TDA7250 Amp
TDA7250 in Pro Use
Cheers
At http://www.ampslab.com/ia502schema.htm is reported to use the 142/147 and u say to don't use them.. why?
And i saw "input sensitivity 1v".. This mean that if my car stereo give and output of 30mV@360mA i can't hear nothing. Right?
check your rails for power...if there is...check for any obvious connecion problems and heating...
Sure and the power is less than 1v so if i'm not wrong this mean that all the power is take from the circuit right?
I'll make some now.. if u'll be patient! 😉
I would dare to say that probably your PSU is not working well...try it without he switchmode PSU...use a "standard" PSU to power it up and test...before you proceed to the SMPSU...
How? I don't own a 220v=>40-0-40 transformer and i don't think that i can find a commercial one...
Anyway i've tested the PSU and a it produce 2.2A from 1.4A as input. Infact i use a 220=>+14V@1.5A to feed the SMPS(my old Creative supply 🙂).
So u think my problem is the SMPS????
Anyway i've tested the PSU and a it produce 2.2A from 1.4A as input. Infact i use a 220=>+14V@1.5A to feed the SMPS(my old Creative supply 🙂).
So u think my problem is the SMPS????
An externally hosted image should be here but it was not working when we last tested it.
You really should heatsink the Darlingtons...and try another PSU...seems to be the SMPSU...under a volt...under load is not a good thing...
Absolutely but for the moment that was only for a test... 🙂
BUt this should be mean that thecircuit take all the curren/voltage or not?
Even if they take all the current..the voltage should not "drop" meaning the SMPSU might not be giving enough power to the amp...OR the amp is having a really heavy short which is causing such a BIG current draw...but since you told me it's less than 1 amp current drawn...I'm not really sure the figures tally...so might be your SMPSU...
I don't understand so clearly.. u say that the voltage is too low for th amp... my SMPS don't produce enough current?
Yup...your SMPSU is not having enough current...but the voltage is probably enough...only because the amp draws a big current does the voltage dip...
So my problem maybe only the current...
I've made a check...
At the input of primary 9A.. output of each secondary...0.5A!!! AAAAAAAAAAAHHHHHHHHHHH!!!! 🙂
What maybe? Wrong frequency? Wrong winding of transformer?
I've made a check...
At the input of primary 9A.. output of each secondary...0.5A!!! AAAAAAAAAAAHHHHHHHHHHH!!!! 🙂
What maybe? Wrong frequency? Wrong winding of transformer?
COuld u explain this to me?
An externally hosted image should be here but it was not working when we last tested it.
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