THAT4311

Wireless microphone systems

Wireless in-ear monitors

Compressors and Limiters

Gates

De-Essers

Duckers

The THAT 4311 Low Power Dynamics Processor combines in a single IC all the active circuitry needed to construct a wide range of dynamics processors. The 4311 includes a high performance, voltage controlled amplifier, a log responding RMS-level sensor and three opamps, one of which is dedicated to the VCA, while the other two may be used for the signal path or control voltage processing.

The exponentially-controlled VCA provides two opposing-polarity, voltage sensitive control ports. Dynamic range exceeds 105 dB, and THD is typically 0.09% at 0dB gain. The RMS detector
provides accurate RMS to DC conversion over an 80 dB dynamic range.

Though originally designed for use in microphone noise reduction systems, the 4311 is a useful building block in a number of analog signal processing applications. The combination of exponential VCA gain control and logarithmic detector response - "decibel-linear" response - simplifies the mathematics of designing the control paths of dynamics processors, making it easy to develop audio compressors, limiters, gates, expanders,
de-essers, duckers, and the like. The high level of integration ensures excellent temperature tracking between the VCA and the detector, while minimizing the external parts count.