TDA7498E don't produce any sound (red Amplifier module)

[manojtm]

Hi,

Is that capacitor i mark on picture i need to replace?

yes

I know this values (DC voltage) from the amplifier in outputs speakers can damage my speakers,

No it will not damage your speaker (you measured with GND, it shows +ve DC volt on all speaker line)because your SPK not connect with GND (it's BTL mode only)

 

[Jorgesilva]

Hi,

yes


No it will not damage your speaker (you measured with GND, it shows +ve DC volt on all speaker line)because your SPK not connect with GND (it's BTL mode only)

Hi my dear NANOJ, i hope you have an nice day.
I will try replace this capacitor.
I measure the outputs terminal from the speakers (L+ L- / R+ R-) and the voltage reading is not mvolts, is volts and my speaker i test it smell like burning, why?
It's all connect the right way, can you explain me what's happen?

Best regards.

 

[djtxop]

Hi . I have the similar problem with a red board sanwu 7498E.
It doesnt make sound. No parts burned. No D8 diode...
Cold you fix it?

I will try to meassure the pins of the chip with voltimeter, but they are so small. Any tip to do that?
Sorry, I am a 39 years old beginner in electronics

 

[afterlife2]

I also have a 7498 with no sound. Any fixes guys. Some pics of mine. Tested 9-24 volt still no sound. Bought a year and sat there till 2 weeks ago. Contacted the seller to see if he has any advice. I'm sure it's too late to get it replaced.

 

[djtxop]

I return to the subject. When I removed the heatsink from the red 7498E board, I saw that the circuit was a 7498 without E. The seller gave me my money back. I ordered another 7498E board, this one is black and it doesn't sound either (they also gave me money back).
I feed it with a 90W 20Vdc laptop power supply, speakers are 6Ohm 60w
No things burned. Led power ON.
I have changed the gain jumper for 33.1db (by default) to 23.6dB, same result.no sound.
Measurements (and photo with points were I'm metering, same as 7498E pins):
20: 2.9V
21: 2.77v
22: 0.02V
29: 0.8V
*note: the voltimeter I have now is a little bad

Should I need change pin29 capacitor 10uF?

Hi,
check PIN 20 & PIN 21= 3V if yes then replace 10uF capacitor (SMD) connected in PIN 29 to GND
MANOJ

Do you know other points to test it?

I will try replace this capacitor.

Could you do change it?

Thank you in advance

 

[djtxop]

more measurements:
pin 6-7 (PVCCB):21V
pin 12-13(PVCCA):21V
pin35 (SVCC):0V
18 (PGND)0V
19 (VDDPW)= 0V
20(STBY): 2.9V
21(MUTE): 2.77v
22(INPA): 0.02V
29 (SVR) =0.3V
34 VREF=0,15V but its decreasing connected with the voltimeter
36 VSS=0v

may be 7498E broken?

 

[djtxop]

pin36=0v
pin35=0v
pin34 =0,4V (dercress when connect the multimeter, i think always is a half of pin 29)
pin 29=0,8V(dercress when connect the multimeter)
pin 28=0V
pin 27=0V
pin 26=0V
pin 22=0V
pin21 =2,8v
pin 20=2,8V