SA575 Low Voltage Compandor The SA575 is a precision dual gain control circuit designed for low voltage applications. The SA575s channel 1 is an expandor, while channel 2 can be configured either for expandor, compressor, or automatic level controller (ALC) application. Features SA575 0.1 F V +5V CC C 15 GND + 10 F 1 20 575 V CC V IN + + C 2 19 R 14 13 OP AMP V C 3 REF 10k V 3 18 OUT + OP AMP 10 F 4 17 3.8k C 11 + 5 16 4.7 F + C 3.8k RECT C 10 C RECT 2.2 F + 6 15 V OUT + 2.2 F GND 10 F C 6 7 14 V 10k IN + 10 F R V 8 V 8 13 REF REF 30k 10k R 7 + 9 12 G 10 F + 10k 30k 1 F C 8 G 10 11 10k GND GND GND GND Figure 1. Block Diagram and Test Circuit PIN FUNCTION DESCRIPTION Pin Symbol Description 1 +V NonInverted Input 1 IN1 2 V Inverted Input 1 IN1 3 V Output OUT 4 RECT. IN1 Rectifier 1 Input 5 C External Capacitor Pinout for Rectifier 1 RECT1 6 SUM OUT1 Summation Output 1 7 COMP. IN1 Compensator Pin 8 V Voltage Reference REF 9 GAIN CELL IN1 Variable Gain Cell Input 1 10 GND Ground 11 GAIN CELL IN2 Variable Gain Cell Input 2 12 SUM NODE 2 Summation Node 2 13 COMP. IN2 Compensator Pin 14 SUM OUT2 Summation Output 2 15 C External Capacitor Pinout for Rectifier 2 RECT2 16 RECT. IN2 Rectifier 2 Input 17 V Output 2 OUT2 18 V Inverted Input 2 IN2 19 +V NonInverted Input 2 IN2 20 V Positive Power Supply CC