Battery-less electronic device
View Patent ↗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.
1. A battery-powered portable electronic device comprising:
a serial bus interface for providing serial communications to the electronic device via a connected serial cable having an information pin and a power pin;
a turn-on circuit electrically coupled to the information pin and a power pin of the serial bus interface, wherein, in response to a non-standard signal received on the information pin, the turn-on circuit: (1) generates a mode signal for the electronic device, and (2) enables power to be supplied to the electronic device from the power pin;
a comparator receiving a reference voltage at a first input of the comparator and an identification signal from the serial bus interface at a second input of the comparator, and generating a comparison signal on an output of the comparator when the identification signal is non-standard as indicated by a comparison to the reference voltage, wherein the output of the comparator is coupled to the electronic device that enters a unique mode of operation in response to receiving the comparison signal; and
a voltage regulator receiving a power signal from the serial bus interface at a first input of the voltage regulator and being electrically coupled to the output of the comparator at a second input of the voltage regulator, wherein the voltage regulator is enabled to generate a power supply on an output of the voltage regulator in response to the comparison signal.
2. The device of claim 1 , further wherein the mode signal indicates to the electronic device to enter into a special mode of operation.
3. The device of claim 2 , wherein the special mode of operation enables the electronic device to load software transmitted over the serial cable.
4. The device of claim 1 , wherein the serial bus interface is a USB On-The-Go connector.
5. The device of claim 1 , wherein the information pin is an identification pin.
6. The device of claim 1 , wherein the electronic device is capable of being battery-powered but a battery is not present and powering the electronic device when the non-standard signal is received.
7. The device of claim 1 , wherein the electronic device is a wireless mobile communication device.
8. The device of claim 1 , wherein the comparison signal indicates to the electronic device to automatically turn on and enter into the unique mode of operation.
9. The device of claim 1 , wherein the unique mode of operation indicates a software download mode of operation for the electronic device.
10. The device of claim 1 , wherein the unique mode of operation indicates a testing mode of operation for the electronic device.
11. The device of claim 1 , wherein the comparison signal generates an interrupt within the electronic device to begin software loading via the serial bus interface.
12. The device of claim 1 , wherein the comparator is a depletion mode comparator.
13. The device of claim 1 , wherein the electronic device is capable of being battery-powered but a battery is not present and powering the electronic device when entering the unique mode of operation.