Abstract: Systems, methods, and apparatus for testing devices adapted for connection to other devices using universal serial bus (USB) are disclosed. Devices to be tested are caused to enter a special mode of operation when resistance measured at one or more terminals of a USB Type-C connector have values associated with the special mode of operation. One or more operations of the device are automatically initiated when the resistance coupled to the at least one terminal of the connector has a measured value that matches one of a set of resistance values maintained by the device. The one or more operations may include configuring a power management circuit based on the measured value, and entering a mode of operation that controls startup of at least one processor on the device when the measured value matches a first resistance value.

Abstract: Systems, methods, and apparatus for testing devices adapted for connection to other devices using universal serial bus (USB) are disclosed. Devices to be tested are caused to enter a special mode of operation when a resistance measured across across two terminals of a USB Type-C connector has a value associated with the special mode of operation. One or more operations of the device are automatically initiated when the resistance between the two terminals has a measured value that matches one of a set of resistance values maintained by the device. The one or more operations may include configuring a power management circuit based on the measured value, and entering a special or factory boot mode that controls startup of at least one processor on the device based on the measured value. Each of the set of resistance values exceeds a minimum open-circuit resistance value specified for the connector.

Abstract: Systems, methods, and apparatus for testing devices adapted for connection to other devices using universal serial bus (USB) are disclosed. Devices to be tested are caused to enter a special mode of operation when a resistance measured across two terminals of a USB Type-C connector has a value associated with the special mode of operation. One or more operations of the device are automatically initiated when the resistance between the two terminals has a measured value that matches one of a set of resistance values maintained by the device. The one or more operations may include configuring a power management circuit based on the measured value, and entering a special or factory boot mode that controls startup of at least one processor on the device based on the measured value. Each of the set of resistance values exceeds a minimum open-circuit resistance value specified for the connector.

Abstract: Systems, methods, and apparatus for testing devices adapted for connection to other devices using universal serial bus (USB) are disclosed. Devices to be tested are caused to enter a special mode of operation when resistance measured at one or more terminals of a USB Type-C connector have values associated with the special mode of operation. One or more operations of the device are automatically initiated when the resistance coupled to the at least one terminal of the connector has a measured value that matches one of a set of resistance values maintained by the device. The one or more operations may include configuring a power management circuit based on the measured value, and entering a mode of operation that controls startup of at least one processor on the device when the measured value matches a first resistance value.

Abstract: A system for estimating battery state of charge (SoC) includes evaluating a battery model to produce an estimated battery voltage using a previously produced SoC. Current and voltage measurements are combined with the estimated battery voltage to produce a present battery SoC. The battery model may be updated by taking battery measurements when certain conditions occur.

Abstract: In one embodiment the present invention includes a system and method of charging a battery using a switching regulator. In one embodiment, a switching regulator receives an input voltage and input current. The output of the switching regulator is coupled to a battery to be charged. The switching regulator provides a current into the battery that is larger than the current into the switching regulator. As the voltage on the battery increases, the current provided by the switching regulator is reduced. The present invention may be implemented using either analog or digital techniques for reducing the current into the battery as the battery voltage increases.

Abstract: Embodiments of the present invention include techniques for charging a battery using a switching regulator. Some embodiments include programmable switching battery chargers that can be configured using digital techniques. Other embodiments include switching battery chargers that modify the battery current based on sensed circuit conditions such as battery voltage or input current to the switching regulator. In one embodiment, the present invention includes a USB battery charger.