GENERAL DESCRIPTION
The TEA1068 is a bipolar integrated circuit performing all speech and line interface functions required in fully electronic telephone sets. It performs electronic switching between dialling and speech.
   
FEATURES
• Voltage regulator with adjustable static resistance
• Provides supply for external circuitry
• Symmetrical high-impedance inputs (64 kΩ) for
    dynamic, magnetic or piezoelectric microphones
• Asymmetrical high-impedance input (32 kΩ) for electret
    microphone
• Dual-Tone Multi-Frequency (DTMF) signal input with
    confidence tone
• Mute input for pulse or DTMF dialling
• Power down input for pulse dial or register recall
• Receiving amplifier for magnetic, dynamic or
    piezoelectric earpieces
• Large gain setting range on microphone and earpiece
    amplifiers
• Line current-dependent line loss compensation facility
    for microphone and earpiece amplifiers
• Gain control adaptable to exchange supply
• DC line voltage adjustment facility.