QSC Audio PL218A, PL230A EMI Filter Inrush Limiting Main Energy Bank, PLM Control, Amplifier

TECHNICAL OVERVIEW: BLOCK DIAGRAM & OPERATIONAL DETAILS

High Performance Audio. High speed power transistors convert this DC power into the full range audio output which drives the speakers. High-current design and special dual-sense output feedback corrects errors on both sides of the speaker terminals, improving damping and control of speaker motion. The power devices are directly mounted to isolated heat sinks, which form a short, wide air tunnel in front of the fan for optimum cooling.

Each channel has a thermal sensor embedded in its heat sink for accurate temperature monitoring. The sensor controls fan speed, bias tracking and thermal shutdown. It also reports temperature readings to the DataPort (for remote monitoring with QSC's CM16a Processor).

The output circuitry is actively clamped during clipping for smooth and very fast recovery. The clamp also feeds a proportional clip limiter, which actually senses the depth of clipping and responds accordingly.

The balanced inputs use premium 0.1% precision resistors for very high noise rejection. The precision components used in the input filters and all other circuitry ensure accurate performance.

Shutdown. The amplifier mutes as soon as power is shut off, preventing turn-off noises. Serious faults trigger a shutdown of the power supply; the high switching frequency allows the power supply to shut down within microseconds to limit damage.

Control Power

EMI Filter

Inrush Limiting

Main Energy Bank

PLM

Control

PowerLight Switching

Transformer

DC Supply for

Amplifier

Basic functional block diagram of PowerLight™ power supply

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