tea1099h NXP Semiconductors, tea1099h Datasheet - Page 2

• Manufacturer Part Number: tea1099h
• Description: Speech And Handsfree Ic With Auxiliary Inputs/outputs And Analog Multiplexer
• Manufacturer: NXP Semiconductors

Philips Semiconductors
FEATURES
Line interface
Supplies
Handsfree
1999 Apr 08
Low DC line voltage
Voltage regulator with adjustable DC voltage
Symmetrical high impedance inputs (70 k ) for
dynamic, magnetic or electret microphones
Dual Tone Multi-Frequency (DTMF) input with
confidence tone on earphone and/or loudspeaker
Receive amplifier for dynamic, magnetic or
piezo-electric earpieces (with externally adjustable gain)
AGC: Automatic Gain Control for true line loss
compensation.
Provides a strong 3.35 V regulated supply for
microcontroller or dialler
Provides filtered power supply, optimized according to
line current and compatible with external voltage or
current sources
Filtered 2.0 V power supply output for electret
microphone
Compatible with a ringer mode
Power-Down (PD) logic input for power-down.
Asymmetrical high-impedance input for electret
microphone
Loudspeaker amplifier with single-ended rail-to-rail
output and externally adjustable gain
Dynamic limiter on loudspeaker amplifier to prevent
distortion
Logarithmic volume control on loudspeaker amplifier via
linear potentiometer
Duplex controller consisting of:
– Signal and noise envelope monitors for both
– Decision logic (with adjustable switch-over and Idle
– Voice switch control (with adjustable switching range
Speech and handsfree IC with auxiliary
inputs/outputs and analog multiplexer
channels (with adjustable sensitivities and timing)
mode timing)
and constant sum of gain during switching).
2
Auxiliary interfaces
APPLICATIONS
GENERAL DESCRIPTION
The TEA1099H is an analog bipolar circuit dedicated for
telephone applications. It includes a line interface, handset
(HS) microphone and earpiece amplifiers, handsfree (HF)
microphone and loudspeaker amplifiers, some specific
auxiliary Inputs/Outputs (I/Os) and an analog multiplexer
to enable the right transmit and/or receive channels.
The multiplexer is controlled by a logic circuit which
decodes four logic inputs provided by a microcontroller.
Thirteen different application modes have been defined
and can be accessed by selecting the right logic inputs.
An application mode is a special combination of transmit
and receive channels required by telephone applications.
This IC can be supplied by the line and/or by the mains if
available (in a cordless telephone or an answering
machine for example). It provides a 3.35 V supply for a
microcontroller or dialler and a 2.0 V filtered voltage supply
for an electret microphone. The IC is designed to facilitate
the use of the loudspeaker amplifier during ringing phase.
General auxiliary output for transmit and receive
purposes
Auxiliary transmit input with high signal level capability
dedicated to line transmission
Auxiliary receive input with high signal level capability
Integrated multiplexer for channels selection.
Line powered telephone sets
Cordless telephones
Fax machines
Answering machines.
Product specification
TEA1099H