LS285A
LS285A is TELEPHONE SPEECH CIRCUITS manufactured by SGS.
LINEAR INTEGRATED CIRCUITS
TELEPHONE SPEECH CIRCUITS
The LS285 and LS285A are monolithic integrated circuits for replacement of the hybrid circuit (2-4 wire interface) in conventional telephones interfacing the two transducers to the line and providing a controlled amount of sidetone. The same type of transducer can be used for both transmitter and receiver, usually a 3500 dynamic type. By sensing the line current, LS285 and LS285A adjust the gain in both directions to pensate for line attenuation. Output impedance can be matched to the line, independent of transducer impedance. The LS285 and LS285A are packaged in a 14 lead dual in-line plastic package.
ABSOLUTE MAXIMUM RATINGS
Line voltage (3 ms pulse duration) Forward current Reverse current
Total power dissipation at Tamb = 70°C
Storage and junction temperature Operating temperature
22 V 120 m A -150 m A
1W -55 to 150 °c -40 to 70°C
ORDERING NUMBERS: LS285 B LS285 AB
MECHANICAL DATA
Dimensions in mm
6/82
CONNECTION...
