Description
Low voltage transmission circuits with dialler interface :
TEA***2
FEATURES
· Low DC line voltage; operates down to 1.6 V (excluding
polarity guard)
· Voltage regulator with adjustable static resistance
· Provides a supply for external circuits
· Symmetrical high-impedance inputs (*4 kW) for
dynamic, magnetic or piezoelectric microphones
· Asymmetrical high-impedance input (*2 kW) for electret
microphones
· DTMF signal input with confidence tone
· Mute input for pulse or DTMF dialling
– TEA***2: active HIGH (MUTE)
– TEA***2A: active LOW (MUTE)
· Receiving amplifier for dynamic, magnetic or
piezoelectric earpieces
· Large gain setting ranges on microphone and earpiece
amplifiers
· Line loss compensation (line current dependent) for
microphone and earpiece amplifiers
· Gain control curve adaptable to exchange supply
· DC line voltage adjustment facility.
