Texas Instruments TAS5001-5122C2EVM, Руководство пользователя

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Description of Indicators
2-8
2.6 Description of Indicators
2.6.1 Power LED (LED223)
The green LED indicates that the control circuitry at the TAS5001−
5122C2EVM board is powered on.
2.6.2 No S/PDIF Input LED (LED222)
The yellow LED indicates that the S/PDIF input signal is missing or it does not
contain valid audio data.
Reasons to have a No S/PDIF warning:
-
The lever at the S/PDIF input selector switch (S100) is placed in the wrong
position.
-
The S/PDIF signal is missing. Some DVD players remove the S/PDIF
output signal when the drawer is opened.
Note:
When the SPDIF−MUTE signal from the S/PDIF receiver is disabled
(JMP130 is shunting pin 2 and pin 3), the No S/PDIF indication is disabled.
2.6.3 Temperature Warning LED (LED221)
The yellow LED indicates that the temperature of the TAS5122 junction has
reached the warning level. This is step one of the two-step thermal protection
system implemented in the TAS5122 device. The temperature warning is an
indication only; the operation of the system is unchanged. If the temperature
increases further and above the shutdown level, the error latch is set and the
system goes into RESET mode. At this point, the Protection Mode LED will be
lit as well as the Temperature Warning LED.
2.6.4 Protection Mode LED (LED220)
The red LED indicates that protection circuit is engaged and it has put the
output stage in shutdown mode.
Possible causes for shutdown mode:
-
Two speaker terminals are shorted
-
The amplifier is constantly overloaded (decrease volume level).
-
One speaker terminal is shorted to ground (f.ex. through an oscilloscope)
-
The output stage is in thermal shutdown due to overload.
Check the setup and board carefully and remove the cause of the failure before
pressing RESET (S620) to disengage the protection mode.