International Rectifier IRAUDAMP4, Руководство пользователя

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RD-0617
Under-Voltage Protection (UVP)
UVP will shutdown the amplifier if the bus voltage between GND and -B falls below 20 V.
The threshold is determined by the voltages sum of the Zener diode Z107, R145 and V
BE
of Q110. Same as OVP, UVP will automatically reset after three seconds and only one
of the two supply voltages is monitored.
Speaker DC-Voltage Protection (DCP)
DCP is provided to protect against DC current flowing into the speakers. This abnormal
condition is rare and is likely caused when the power amplifier fails and one of the high-
side or low-side IRF6645 DirectFET MOSFETs remain in the ON state. DCP is activated
if either of the outputs has more than ±4 V DC offset (typical). Under this fault condition,
it is normally required to shutdown the feeding power supplies. Since these are external
to the reference design board, an isolated relay is provided (P1) for further systematic
evaluation of DC-voltage protection to transmit this condition to the power supply
controller and is accessible through connector J9 (pins of J9 are shorted during fault
condition).