U4087B

Features:

Low voltage operation: 3.0 to 7.0 V
Four point signal sensing
Monitoring system for background noise level
Case: SO 16
Chip Disable for active/standby operation


Specifications

Parameters	Symbol	Value	Unit
Supply voltage                                                            Pin 7	VB	0.3 to + 12	V
Voltages:                                                                    Pin 6                                                                                    Pin 13		0.3 to 6 0.3 to (VB + 0.3)	V
Storage temperature range	Tstg	55 to + 150	°C
Junction temperature	Tj	125	°C
Ambient temperature range	Tamb	20 to + 60	°C
Power dissipation                        Tamb = 60 °C       SO 16	Ptot	750	mW
Maximum thermal resistance Junction ambient          SO 16	RthJA	110	K/W

Description

The voice switch interface circuit U4087B is a linear integrated circuit for improvement of handsfree performance of U4090B system.

The U4087B provides an optimized interface to U4090B, the necessary level detectors and switching control for a properly operating speakerphone. The detection sensitivity and timing are externally controllable. Additionally, the U4087B provides a back- ground noise monitor which makes the circuit insensitive to room noise.

The Block diagram U4087B shows level detectors, back ground noise monitor.

Due to low voltage operation U4087B can be operated via power supply management of U4090B requiring 1.0 mA typ.