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LOW VOLTAGE TELEPHONE SPEECH CIRCUITS
OPERATIONDOWNTO 1.6V / 6.5mA
DTMF & BEEP TONE INPUTS
EXTERNAL MUTING FOR EARPHONE AND
MICROPHONE
SUITABLE FOR DYNAMIC EARPHONE AND
DYNAMIC OR ELECTRETMICROPHONE
AGC CONTROL ON BOTH SENDING AND
RECEIVING
DIP14
L3281
PRELIMINARY DATA
SO14
DESCRIPTION
The L3281 is an electronic speech circuit developed to replace hybrid circuits in telephone sets
that can be operated in parallel with other
phones.
BLOCK DIAGRAM
ORDERING NUMBERS:
L3281AB L3281AD1
June 1993
This is advancedinformationon a new product now in development or undergoing evaluation. Details are subject to change without notice.
1/10
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L3281
PIN CONNECTION (top view)
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter
V
L
I
L
P
tot
T
op
T
j
Line Voltage (3 ms pulse) 15 V
Line Current 150 mA
Total Power Dissipation, T
Operating Temperature – 20 to 55 °C
Junction Temperature – 65 to 150 °C
THERMAL DATA
Symbol Parameter
R
th j-amb
Thermal Resistance Junction Ambient Max 90 130 °C/W
Value
DIP-14 SO-14
=55°C 1.0 0.6 W
amb
Value
DIP-14 SO-14
Unit
Unit
2/10