KA8512

KA8512 COMPANDOR INTRODUCTION Compandor is a composite word of compressor and expander. It is used for maintaining dynamic range and improving of S/N ratio, and generally called as a noise reduction system or automatic gain control system. KA8512 consists of compressor, expander, mic amp, Iimiter, ALC(automatic level control) and mute logic. 14-DIP-300 FEATURES Operating voltage range : 2 ~ 6V Included ALC circuit Easy gain control to use external component Included mute function 14-SOP-225B ORDERING INFORMATION Device KA8512 KA8512D Package 14-DIP-300 14-SOP-225B Operating Temperature -20°C ~ + 70°C BLOCK DIAGRAM EPI ERC EMUTE CMUTE 2 15K 3 RECTIFIER 30K 5 6 MUTE LOGIC 10K GAIN CELL G 10K _ 4 VREF + SUM AMP + LIMITER VREF _ 24K 30K 10K 15K GAIN CELL G ALC 15K + MIC AMP 51K EO + CO VREF 3.3K 12 _ 125K 125K _ 30K 9 8 11 CPICPI+ AGIC 13 ALC BIAS CIRCUIT RETIFIER 7 GND 14 VCC 1 VREF 10 CRC KA8512 COMPANDOR PIN CONFIGURATION VR E F EPI ERC EO EMUTE CMUTE GND 1 2 3 4 5 6 7 KA8512 14 13 12 11 10 9 8 VC C ALC CO AGIC CRC CPICPI+ PIN DESCRIPTION Pin No 1 Symbol VREF Description It is a voltage reference (VREF=1V) used for supplying a constant voltage to the compressor and expander of compandor. It is SUM AMP input terminal of expander. The voice signal recoverd after 2 EPI the demodulation waveform from the receiver passed through the 2’ nd order low pass filter enters this terminal. This terminal is used for converting waveform from the fu...