TS34118 Datasheet, PDF (1/20 Pages) Taiwan Semiconductor Company, Ltd – Voice Switched Speakerphone Circuit

SOP-28
TS34118
Voice Switched Speakerphone Circuit
DIP-28
Supply Voltage Range -1.0 V to 7.0V
I_VB Current 500µA
Microphone Amplifier, & Hybrid Amplifier
Gain 40 dB
General Description
The TS34118 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 being attenuated by the Receive background noise monitor
circuit. Also included are two line drive 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 60Hz noise in the receive 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 TS34118 may be operated from a power supply, or it can be powered from the telephone line, requiring typically
5.0mA. The TS34118 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 feature phone
Features
— Improved attenuator gain range: 52dB between
transmit and receive.
— Low voltage operation for line-powered applications
(3.0-6.5V).
— 4-point signal sensing for improved sensitivity.
— Back ground 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 defined function.
— Dial tone detector to inhibit receive idle mode during
dial tone presence.
— Compatible with TS34119 speaker amplifier.
— Standard 28-pin plastic DIP package and SOP
package available.
Ordering Information
Part No.
TS34118CD
TS34118CS
Operating Temp.
-20 ~ +70 ^oC
Package
DIP-28
SOP-28
Absolute Maximum Rating
Description
Supply voltage (pin 4)
Voltage at CD (pin 3), MUT (pin 12)
Voltage at VLC (pin 13)
Voltage at TXI (pin 9),RXI (pin 21),FI(pin 2)
Storage temperature range
Value
-1.0, +7.0
-1.0,Vcc +1.0
-1.0,Vcc +0.5
-0.5,Vcc +0.5
-65 to +150
Unit
V
V
V
V
o_C
TS34118
1-20
2004/09 rev. B