Samsung semiconductor KA8504
The KA8504 is a telephone speech network which includes TX Amp, RX Amp and DTMF Amp. The gain is controlled automatically by sensing the line current. The circuit internally performs electronic switching between dialing and speech by mute signal.FEATURES
● Low line current operation● Mute function
● DTMF signal interface
● Easy gain control ORDERING INFORMATION Device KA8504 Package 16-DIP-300A Operating Temperature - 40°C ~ + 85°C BLOCK DIAGRAM ROF 14 RXI 13 RX INPUT AMP RX GAIN CONTROL RX OUTPUT AMP 15 RXO GC 12 GAIN CONTROLLER 5 MF 10 VL 1 TX AMP MIC+ TX GAIN CONTROL TX AMP 11 MIC- 2 CI 3 CO 6 MUTE 9 TOF Fig. 1 KA8504 SPEECH NETWORK WITH DIALER INTERFACE PIN CONFIGURATION VL CI CO BIAS MF MUTE VR GND 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 Vcc RXO ROF RXI GC MICMIC+ TOF Fig. 2 PIN
DESCRIPTION
Pin No 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Symbol VL CI CO BIAS MF MUTE VR GND TOF MIC + MIC GC RXI ROF RXO VCCDESCRIPTION
Positive power line and TX Amp Output. Current input. Current output. If the line current is large, this pin dissipates excess power (current) AC signal reference voltage terminal. DTMF input. When the mute pin is “H” level, this pin become active. Mute input. When this pin is 'H’level, speech circuit is muted and the DTMF input is enabled.