Microphone-controller with multifunction, single conductor
US5018188A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 1989 |
| Grant date | May 21, 1991 |
| Priority date | — |
| Expiry date | Dec 20, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W88/02
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The single power conductor carries audio and a serial data bus. The microphone's amplifier (102) is connected to the conductor (108). The incoming audio signal rides on the DC supply voltage from the radiotelephone. The supply voltage, through a voltage regulator (103), supplies power to the amplifier (102) and a microprocessor (105), used to transmit the serial data message on the conductor (108). Both the amplifier (102) and the voltage regulator (103) are isolated from the power conductor (108) by a FET switch (104) that is controlled by the microprocessor (105). The switch (104) is turned off, isolating the circuitry when the microprocessor (105) is transmitting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.