THAT4305

The THAT4305 is a single-chip Analog Engine optimized for low-cost applications. It incorporates a high-performance Blackmer voltagecontrolled amplifier (VCA) and log-responding RMS-level sensor. The VCA and RMS detector are pre-trimmed at wafer stage to deliver low distortion without further adjustment.

Available only in a small (QSOP) surfacemount package, the 4305 is aimed at line-operated audio applications such as compressor/limiters, gates, and other dynamic processors. The part normally operates from a split supply voltage up to ±16Vdc, drawing only 3.5mA at ±15V. This IC also works at supply voltages as low as ±4.5V, making it useful in some battery-operated products as well.

The 4305 was developed specifically for use in low-cost dynamics processors, drawing from THAT's long history and experience with such designs. Both VCA control ports and the detector input and output are available for the designer to connect as s/he sees fit. As a result, the part is extremely flexible and can be configured for a wide range of applications including si ngleand multi-band companders, digital overload protectors, voltage-controlled faders, level indicators, etc.

What really sets the 4305 apart from other manufacturers' offerings is the transparent sound of its Blackmer VCA, coupled with its accurate true-RMS level detector. This makes the IC useful in a wide range of analog audio products.