GENERAL DESCRIPTION
The TEA1113 is a bipolar integrated circuit that performs all speech and line interface functions required in fully electronic telephone sets. It performs electronic switching between speech and dialling. The IC operates at a line voltage down to 1.6 V DC (with reduced performance) to facilitate the use of telephone sets connected in parallel.

FEATURES
• Low DC line voltage; operates down to 1.6 V (excluding polarity guard)
• Voltage regulator with adjustable DC voltage
• Provides a supply for external circuits
• Symmetrical high impedance inputs (64 kΩ) for dynamic, magnetic or piezo-electric microphones
• Asymmetrical high impedance input (32 kΩ) for electret microphones
• DTMF input with confidence tone
• MUTE input for pulse or DTMF dialling
• Receiving amplifier for dynamic, magnetic or piezo-electric earpieces
• Dynamic limitation in the transmit direction to prevent distortion of the transmit line and sidetone signals
• AGC line loss compensation for microphone and earpiece amplifiers
• LED on-hook/off-hook status indication
• Microphone mute function available with switch.

APPLICATION
• Line powered telephone sets, cordless telephones, fax machines and answering machines.