http://www.st.com/resource/en/datasheet/tda7388.pdf
I soldered this amplifier on my test board by the schematic which is attached in their datasheet.
The problem is, amplifier plays audio even when mute is not connected. For the stand by input i used 5V (7805).
I measured mute pin and it was 3.01V. How comes that there is 3V on mute pin which is not even connected? There is no solder bridges or anything, i even lifted that pin up from the board. Tried to ground mute pin with 1.0uf y5v capacitor - the same situation.
I soldered this amplifier on my test board by the schematic which is attached in their datasheet.
The problem is, amplifier plays audio even when mute is not connected. For the stand by input i used 5V (7805).
I measured mute pin and it was 3.01V. How comes that there is 3V on mute pin which is not even connected? There is no solder bridges or anything, i even lifted that pin up from the board. Tried to ground mute pin with 1.0uf y5v capacitor - the same situation.
Mute and Standby are in different sections.
Standby is in the medium current as in driver section.
Mute is in the small current as in input section.
The mute pins are an input.
Give the mute V+ pin a 10k or 20k resistor to power.
Give the mute ground either ground or the +input.
In the following, I have minimized the parts count for these:
Do login for that.
There is possibility of slight error since there could be start-up or shut-off pops/bangs with far less amplitude than could cause significant wear or damage to any relevant speaker connected. The relevant notion is why real racing bicycles never have kickstands. Stuff to use while off is something that I haven't explored.
Standby is in the medium current as in driver section.
Mute is in the small current as in input section.
The mute pins are an input.
Give the mute V+ pin a 10k or 20k resistor to power.
Give the mute ground either ground or the +input.
In the following, I have minimized the parts count for these:
Do login for that.
There is possibility of slight error since there could be start-up or shut-off pops/bangs with far less amplitude than could cause significant wear or damage to any relevant speaker connected. The relevant notion is why real racing bicycles never have kickstands. Stuff to use while off is something that I haven't explored.
Question is still unanswered for me.
Stand-by and mute - both are inputs. Why there is 3volts on mute when its not connected to anything? Might be fake TDA?
Stand-by and mute - both are inputs. Why there is 3volts on mute when its not connected to anything? Might be fake TDA?
No necessarily the chip is bad, perhaps it has its own internal bias at 3V, and you only need to change it to the desired voltage, 0V or 5V in this case.
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