IL34118 Datasheet, PDF (1/12 Pages) Integral Corp. – Voice Switched Speakerphone Circuit

TECHNICAL DATA
Voice Switched Speakerphone Circuit
IL34118
The IL34118 Voice Switched Speakerphone Circuit incorporates
the necessary amplifiers, attenuators, level detectors, and control
algorithm to form the heart of a high quality hands-free speakerphone
system. Included are a microphone amplifier with adjustable gain and
MUTE control, Transmit and Receive attenuators which operate in a
complementary manner, level detectors at both input and output of
both attenuators, and background noise monitors for both the transmit
and receive channels. A Dial Tone Detector prevents the dial tone
from being attenuated by the Receive background noise monitor
circuit. Also included are two line driver amplifiers which can be used
to form a hybrid network in conjunction with an external coupling
transformer. A high pass filter can be used to filter out 60 Hz noise in
the reseive channel, or for other filtering functions. A Chip Disable
pin permits powering down the entire circuit to conserve power on
long loops where loop current is at a minimum.
The IL34118 may be operated from a power supply, or it can be
powered from the telephone line, requiring typically 5.0 mA. The
IL34118 can be interfaced directly to Tip and Ring (through a
coupling transformer) for stand-alone operation, or it can be used in
conjunction with a handset speech network and or other features of a
featurephone.
• Improved Attenuator Gain Range: 52 dB Between Transmit and
Receive
• Low Voltage Operation for Line-Powered Applications (3.0-
6.5 V)
• 4 Point Signal Sensing for Improved Sensitivity
• Background Noise Monitors for Both Transmit and Receive
Paths
• Microphone Amplifier Gain Set by External Resistors - Mute
Function Included
• Chip Disable for Active Standby Operation
• On Board Filter Pinned-Out for User Deined Function
• Dial Tone Detector to Inhibit Receive Idle Mode During Dial
Tone Presence
ORDERING INFORMATION
IL34118N Plastic
IL34118DW SOIC
T_A = -25° to 70° C for all packages
PIN ASSIGNMENT
1