Abstract: Automated software loading into a battery-less mobile phone is accomplished through attachment of a special non-standard USB On-The-Go cable to a serial connector of the mobile phone, thereby delivering power supply and unique signals for placing the phone in a special mode of operation used for production or distribution. In operation, when a unique non-standard voltage is asserted on the identification (ID) pin of the USB connector interface, it is detected by special circuitry in the serial connector. The circuitry then enables power supply to the battery-less phone and generates a turn-on signal directing the mobile phone to automatically power-on and enter into a particular state of operation, for example a test or software loading mode. Because this process is automatic, the efficiency of software loading or testing during production or distribution of the mobile device is improved.

Abstract: A comparator circuit (300) has a first field effect transistor (FET) (307) with a supply voltage (301) connection and a diode connected FET (303) connected in series to form the first circuit leg of the comparator (300). A second diode connected FET (309) and a second FET (305) in series form the second circuit leg. The first FET (307) and said second FET (305) are approximately equal sized FETs. Another embodiment is an integrated circuit (401) with two n-channel FETs. A first diode connected FET (303) is connected to the first n-channel FET (307) in series to form the first circuit leg of a comparator (300) and a second diode connected FET (309) is connected to a second n-channel FET (305) in series to form the second circuit leg of the comparator. The two n-channel FETs that form the differential pair are approximately equal in size. The trip point is high with respect to the supply voltage.

Abstract: A transceiver module can share a common connector with a rechargeable battery connection. The transceiver module can be protected from the high voltages applied by a battery charger. Determining when the voltage applied at a connector exceeds a reference voltage and electrically decoupling the transceiver module from the connector when the reference voltage is exceeded can protect the transceiver module. The reference voltage can be set at a level so that the transceiver is decoupled from the connector when the voltage at the connector reaches a voltage that is unsafe for the transceiver.

Abstract: A comparator circuit (300) has a first field effect transistor (FET) (307) with a supply voltage (301) connection and a diode connected FET (303) connected in series to form the first circuit leg of the comparator (300). A second diode connected FET (309) and a second FET (305) in series form the second circuit leg. The first FET (307) and said second FET (305) are approximately equal sized FETs. Another embodiment is an integrated circuit (401) with two n-channel FETs. A first diode connected FET (303) is connected to the first n-channel FET (307) in series to form the first circuit leg of a comparator (300) and a second diode connected FET (309) is connected to a second n-channel FET (305) in series to form the second circuit leg of the comparator. The two n-channel FETs that form the differential pair are approximately equal in size. The trip point is high with respect to the supply voltage.

Abstract: Automated software loading into a battery-less mobile phone is accomplished through attachment of a special non-standard USB On-The-Go cable to a serial connector of the mobile phone, thereby delivering power supply and unique signals for placing the phone in a special mode of operation used for production or distribution. In operation, when a unique non-standard voltage is asserted on the identification (ID) pin of the USB connector interface, it is detected by special circuitry in the serial connector. The circuitry then enables power supply to the battery-less phone and generates a turn-on signal directing the mobile phone to automatically power-on and enter into a particular state of operation, for example a test or software loading mode. Because this process is automatic, the efficiency of software loading or testing during production or distribution of the mobile device is improved.