> The feedback resistor path needs to be as short as possible.
With the 1519 it's inside the chip :
https://utcdn.utsource.info/goods_files/pdf/19/19205_PHILIPS_TDA1519C.pdf
With the 1519 it's inside the chip :
https://utcdn.utsource.info/goods_files/pdf/19/19205_PHILIPS_TDA1519C.pdf
You use a more rare bridge-coupling.
I found a similar coupling on the net but here they leave out the 100uF capacitor on pin 3. Does that help (quick to try)?
Schematic Reference: November 2013
I found a similar coupling on the net but here they leave out the 100uF capacitor on pin 3. Does that help (quick to try)?
Schematic Reference: November 2013
Hi thanks. I removed the cap bettwwwn Pim 2and 3 with no joy so I decided to start again so I removed all components and started again keeping all paths as short as possible. Now all o get is a series of pops from the speaker and the chip still warns up quickly. I Just can't figure it out all negatives go to pin 5and 2.
Pin 7 is the supply pin. You have 3V on that pin. Minimum operating voltage is 6V. Have you intentionally used a 3V supply or has the supply simply collapsed under too much loading?
First mandatory action: raise the supply voltage to at least 6V.
Pin 6 is at 0V. It is one of the two outputs. Pin 4 is the other output having at least a very small voltage (0.02v-0.1V). Is there a possibility that pin 6 is shorted to GND (please check with an Ohm-meter with power OFF)?
First mandatory action: raise the supply voltage to at least 6V.
Pin 6 is at 0V. It is one of the two outputs. Pin 4 is the other output having at least a very small voltage (0.02v-0.1V). Is there a possibility that pin 6 is shorted to GND (please check with an Ohm-meter with power OFF)?
At least the voltages got up. It still looks suspicious because the supply voltage is not stable at 14V but is being pulled down to 8 volt by some dramatic consumption of the chip.
What is the current capacity (Amps) of your 14V supply? It must be at least around 1 Ampere.
There is a possibility that the TDA1519 chip has been damaged (destroyed) by a short-circuit like the one between pins 6 and 7 (forcing an output to the supply voltage). We will have to bring the chip to a state where no outputs are loaded and all inputs are put at a sensible level:
* Disconnect the speaker such that the outputs (pins 4 and 6) are floating.
* The inputs (pin 1 and pin 9) should be connected together after the input capacitor but the pins have a different voltage (pin 1 0V/ pin 9 0.3V). Is it possible that pin 1 (0V) is short-circuited to GND (measure with an Ohm-meter, without power)? Also, measure without power and the Ohm-meter if the pins 1 and 9 are really connected together (close to 0 Ohm) and only to the 220nF input capacitor?
* Pin 7 (supply) and pin 8 (mute) should be connected together (through the switch) but your measurements show that they do not follow one another in voltage (8-12V/8-14V). Are they really connected together through the switch?
* Pin 3 is an output, generated by the chip, and should show half the supply voltage, but it doesn't. This is an indication that the chip may be defect, but it may also be caused by an input (pins 1 and 9) if one of the inputs are shorted to GND.
* I know this sounds silly but please check that the two GND pins (pins 2 and 5) are really connected to GND (with an Ohm-meter and without power).
Will you please do these checks and give me the pin voltages for all pins again (with pin 8 connected to pin 7 / not muted)?
What is the current capacity (Amps) of your 14V supply? It must be at least around 1 Ampere.
There is a possibility that the TDA1519 chip has been damaged (destroyed) by a short-circuit like the one between pins 6 and 7 (forcing an output to the supply voltage). We will have to bring the chip to a state where no outputs are loaded and all inputs are put at a sensible level:
* Disconnect the speaker such that the outputs (pins 4 and 6) are floating.
* The inputs (pin 1 and pin 9) should be connected together after the input capacitor but the pins have a different voltage (pin 1 0V/ pin 9 0.3V). Is it possible that pin 1 (0V) is short-circuited to GND (measure with an Ohm-meter, without power)? Also, measure without power and the Ohm-meter if the pins 1 and 9 are really connected together (close to 0 Ohm) and only to the 220nF input capacitor?
* Pin 7 (supply) and pin 8 (mute) should be connected together (through the switch) but your measurements show that they do not follow one another in voltage (8-12V/8-14V). Are they really connected together through the switch?
* Pin 3 is an output, generated by the chip, and should show half the supply voltage, but it doesn't. This is an indication that the chip may be defect, but it may also be caused by an input (pins 1 and 9) if one of the inputs are shorted to GND.
* I know this sounds silly but please check that the two GND pins (pins 2 and 5) are really connected to GND (with an Ohm-meter and without power).
Will you please do these checks and give me the pin voltages for all pins again (with pin 8 connected to pin 7 / not muted)?
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1) Hi my power supply is 1 amp
2) There is no short on pin 1 or 9
3) pin 1 & 9 are connected and only to the 220nf cap
4) pin 7 & 8 do only connect through the switch
5) pins 2 & 5 are connected to the ground on the psu
Test conducted without output connected with input connected.
p1-0.04
p2-gnd
p3-7.74
p4-0.24
p5-gnd
p6-15.26
p7-16.15
p8-16.15
p9-2.14
all voltages stable
tested psu out of circuit and it tested 16.15v just as a mater if interest.
thanks.
2) There is no short on pin 1 or 9
3) pin 1 & 9 are connected and only to the 220nf cap
4) pin 7 & 8 do only connect through the switch
5) pins 2 & 5 are connected to the ground on the psu
Test conducted without output connected with input connected.
p1-0.04
p2-gnd
p3-7.74
p4-0.24
p5-gnd
p6-15.26
p7-16.15
p8-16.15
p9-2.14
all voltages stable
tested psu out of circuit and it tested 16.15v just as a mater if interest.
thanks.
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Thanks for the measurements. Now it starts looking more understandable, but unfortunately also like the TDA-chip is defect:
* The supply voltage is stable at the voltage supplied by the power supply. Good.
* The voltage at pin 3 is now close to half the supply voltage as it should. Good.
* The two outputs (pins 4 and 6) should be at the level of pin 3, but they are absolutely not (0.24V/15.26V). This explains why the supply voltage was pulled down when the speaker was connected. Either the TDA1519 chip is defect or there remains a problem at the inputs.
* The inputs (pin 1 and pin 9) are at 0.04V and 2.14V respectively. I know you have measured this, but it is not possible that they are connected to one another by a low impedance connection if the voltages are different. Here remains a problem. Please disconnect the two inputs from one another and the input capacitor such that both inputs are fully floating on their own with no connections to anything.
If the outputs do not return to around the voltage at pin 3, the chip is (unfortunately) defect.
* The supply voltage is stable at the voltage supplied by the power supply. Good.
* The voltage at pin 3 is now close to half the supply voltage as it should. Good.
* The two outputs (pins 4 and 6) should be at the level of pin 3, but they are absolutely not (0.24V/15.26V). This explains why the supply voltage was pulled down when the speaker was connected. Either the TDA1519 chip is defect or there remains a problem at the inputs.
* The inputs (pin 1 and pin 9) are at 0.04V and 2.14V respectively. I know you have measured this, but it is not possible that they are connected to one another by a low impedance connection if the voltages are different. Here remains a problem. Please disconnect the two inputs from one another and the input capacitor such that both inputs are fully floating on their own with no connections to anything.
If the outputs do not return to around the voltage at pin 3, the chip is (unfortunately) defect.
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OK so I'm making a little progress. I wasn't getting anywhere with the step board and fearing I had damaged the chip so I removed the chip from board and proceeded to hard wire it up using the same components as before removed from the board and hey presto worked first time. I still don't understand what did wrong on the board but at least I know that all the components work.
I am happy to hear nothing is damaged.
Next time you have a DIY amplifier ready, do not connect the speakers right away, unless it is class D (may be damaged if turned ON without a load). First, check all connections twice then turn the power ON and measure all DC voltages before connecting the speaker. If you measure a DC voltage exceeding 200mV on the speaker terminals, do not connect the speaker!
Good luck with your DIY.
Next time you have a DIY amplifier ready, do not connect the speakers right away, unless it is class D (may be damaged if turned ON without a load). First, check all connections twice then turn the power ON and measure all DC voltages before connecting the speaker. If you measure a DC voltage exceeding 200mV on the speaker terminals, do not connect the speaker!
Good luck with your DIY.
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