There are probably 2 diodes that connect to pins 1 and 7 of the 393. If so, which output (1 or 7) goes high when the amp goes into protect?
Ok, So after testing I have found the protect signal is coming from the overcurrent system. When the connection from PIN8 of the audio driver board to PIN11 of the PS driver board is removed, the amplifier never protects. However, PIN 8 of the audio driver board intermittently outputs ~13V. Other times it is only <300mV.
Even when the output of PIN 8 is 13V, and the connection to the PS driver board is removed, the amplifier powers up fine with no DC offset or excessive current draw.
What should I look for that would cause a false over-current protect signal from the audio driver board?
Even when the output of PIN 8 is 13V, and the connection to the PS driver board is removed, the amplifier powers up fine with no DC offset or excessive current draw.
What should I look for that would cause a false over-current protect signal from the audio driver board?
With the black probe on pin 4 of the LM393 (or on the negative rail pin of the driver board), post the DC voltage on the rest of the pins of the LM393 with as much resolution as your meter can display.
What state would you like the amplifier in when testing this? With the amp not in protect? When the connection between audio driver board and PS driver board is broken and audio driver board is showing 13V on the protect line? Or with the connection replaced and the amp in protect?
Amp powered up, no protect, connection from audio driver board to PS driver board disconnected, but Audio driver board outputting 13V on PIN8.
LM393
PIN1 = 131.2mV
PIN2 = 2.491V
PIN3 = 1.150V (And dropping as I was taking reading)
------------------
PIN5 = 1.032V
PIN6 = 2.914V
PIN7 = 133.5mV
PIN8 = 14.70V
LM393
PIN1 = 131.2mV
PIN2 = 2.491V
PIN3 = 1.150V (And dropping as I was taking reading)
------------------
PIN5 = 1.032V
PIN6 = 2.914V
PIN7 = 133.5mV
PIN8 = 14.70V
A couple of things...
Does this amp drive pin 8 from the 12v external regulator? If so, it appears to be out of tolerance.
With the voltages posted, the output from pin 8 should be near 0v.
Pin 6 should be connected to a low value resistor (270-330 ohms typically). The voltage on that pin is typically very low. Confirm and check that resistor.
Is this a 2610 or a 1216 driver board?
Does this amp drive pin 8 from the 12v external regulator? If so, it appears to be out of tolerance.
With the voltages posted, the output from pin 8 should be near 0v.
Pin 6 should be connected to a low value resistor (270-330 ohms typically). The voltage on that pin is typically very low. Confirm and check that resistor.
Is this a 2610 or a 1216 driver board?
Wait I think I screwed this up. Is this supposed to be U1 on the audio driver board? These readings are from the 393 on the PS board.
it is a DWM1216
it is a DWM1216
lm393 on audio driver board U1
PIN1 = 90.1mV
PIN2 = 11.16V
PIN3 = 6.08V
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PIN5 = 393.7mV
PIN6 = 0.00V
PIN7 = 12.24V
PIN8 = 12.24V
PIN1 = 90.1mV
PIN2 = 11.16V
PIN3 = 6.08V
---------------
PIN5 = 393.7mV
PIN6 = 0.00V
PIN7 = 12.24V
PIN8 = 12.24V
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