Charging a provider/consumer with a dead battery via USB power delivery

An apparatus that is configured to operate as a consumer/provider, the apparatus comprising:

• an interface having a power bus and a data bus, wherein the interface is configured to be coupled to a cable, and wherein the power bus includes a VBUS conductor and a ground conductor;
• an isolation circuit that is coupled to the VBUS conductor;
• a power system that is configured to be coupled to a power source and that is coupled to an inductor;
• a power transceiver that is coupled to the power system and the VBUS conductor, wherein the power transceiver has a device policy manager and a policy engine, wherein the policy engine is configured to interact with the device policy manager, wherein the power transceiver is configured to:
• check the VBUS conductor to determine whether the voltage on the VBUS conductor is greater than a vSafeOV voltage within a dead battery detect time interval;
• instruct the device policy manager to apply a vSafeDB voltage to the VBUS conductor if the voltage on the VBUS conductor is not greater than the vSafe0V voltage;
• wait for a bit stream to be detected within a bit stream detect time interval;
• instruct the device policy manager to apply the vSafeOV voltage to the VBUS conductor if the bit stream is not detected within the bit stream detect timer interval;
• and
• instruct the device policy manager to apply a vSafe5V voltage to the VBUS conductor if the bit stream is detected;
• and
• send capabilities as a source port after the bit stream has stopped;
• and
• a capacitor that is coupled between the power transceiver and the VBUS conductor;
• wherein the power transceiver is configured to wait for source port capabilities if the voltage on the VBUS conductor is greater than the vSafe0V voltage;
• wherein the power transceiver is configured to instruct the device policy manager to apply the vSafe0V voltage to the VBUS conductor if the device ready timer interval lapses;
• wherein the power transceiver further comprises a controller that is coupled to the VBUS conductor;
• wherein the controller further comprises:
• the device policy manager;
• the policy engine that is configured to communicate with the device policy manager;
• a transmitter that is configured to communicate with the policy engine;
• a receiver that is configured to communicate with the policy engine;
• an interface that is configured to communicate with the transmitter and the receiver and that is coupled to the VBUS conductor;
• wherein the power system further comprises a switching circuit that is coupled between the power converter and the inductor;
• wherein the power transceiver further comprises a state machine that is coupled to the controller;
• wherein the bit stream is detected after a plurality of consecutive bits match an alternating 0 and 1 pattern;
• wherein the power transceiver is configured to:
• wait for the bit stream to stop within a device ready timer interval;
• and
• send capabilities as the source port if the bit stream has stopped within the device ready timer interval.