Dynamic Range Processor Type Ssm2120/2122

APPLICATION NOTES The contents of this column are based on information obtained from manufacturers in the electronics industry, or their representatives, and do not imply practical experience by Elektor Electronics or its consultants. DYNAMIC RANGE PROCESSOR TYPE SSM2120/2122 Integrated circuit Type SSM2120 from Precision Monolithics Inc. is a dynamic range processor designed specifically for use in professional audio systems. The chip, housed in a 22-pin `skinnydip" package, has two fully independent class A voltage controlled amplifiers (VCAs) that exhibit very low distortion and offer a 100 dB dynamic range. Each VCA has two complementary antilog (dB/volt) control ports to simplify system design. Also included on the chip are two in- dependent control side chain circuits, each of which consists of a full-wave rec- tifier, a logging circuit, and a high- impedance amplifier. The log/antilog nature of the control paths makes poss- ible precisely defined compression/ex- pansion rat...