| 摘要 |
PROBLEM TO BE SOLVED: To provide a subscriber line interface circuit(SLIC) provided with a single power source and a voltage regulator. SOLUTION: This SLIC 10 receives power from a single power source 20 and uses a voltage regulator 16 to limit the enter-terminal voltage of a telecommunication unit 26 to a prescribed voltage which is lower than the limit of the industrial standard voltage. The SLIC 10 selectively enables or disables voice amplifiers 12a, 12b, in response to an external control signal independently of the on-hook/off-hook status of the telecommunication unit 26. The SLIC 10 transmits a ringing signal and/or a caller confirmation signal to the telecommunication unit 26 via the voice amplifiers, while the telecommunication unit 26 is hooked on. |
