Revisiting Phantom Power Fault Protection
During a phantom power fault, the negative rail can momentarily drop well below its nominal value, damaging the preamp. In DN201 the mechanisms and consequences of phantom power faults are well explained.
626x Common Mode Operation
This document describes how THAT626x behaves to any DC/AC common-mode input signal, especially AC. The typical bipolar application circuit from the 626x datasheet is used as an example. Since the concern is about the common-mode signal, both phases of the differential path will respond the same way (assuming good matching between the phases). Hence, we’ll examine the response in one phase of the differential path.
Basic Compressor/Limiter Design with the 4305
THAT Corporation’s Analog Engines are ideal basic building blocks for compressor/limiter designs. This design brief describes in detail the circuitry for two basic compressor/limiter designs using the THAT4305 Analog Engine. The first design is an above-threshold, hard-knee compressor with variable ratio, threshold and gain controls. The second design adds a soft-knee threshold. Suggestions for alignment are presented, as are ideas for modifying the basic circuits to allow common variations.