The THAT 4301P Dynamics Processor, dubbed ‘THAT Analog Engine’, combines in a single IC,all the active circuitry needed to construct a wide range of dynamic processors.
The 4301P includes a high-performance, exponentially-controlled VCA, a log-responding RMS-level sensor and three general purpose op-amps.
The VCA provides two opposing ports.
Dynamic range exceeds 115dB, and THD is typically 0.003% at 0dB gain.
The RMS detector provides accurate rms-to dc conversion over an 80 dB dynamic range for signals with crest factors up to 10.
One op-amp is dedicated as a current-to-voltage converter for the VCA, while the other two may be used for the signal path or control voltage processing.
The combination of exponential VCA gain control and logarithmic detector response (‘decibel-linear’ response) simplifies the control path mathematics of the dynamics processors. This makes it easy to design audio compressors, limiters, gates, expanders, de-essers, duckers, noise reduction systems and the like.
The high level of integration ensures excellent temperature tracking between the VCA and detector, while minimising the external parts count.
Demonstration Board THAT4301DEMO is available for this product.