Abstract:
A method and apparatus for adjusting transmission power in a portable two-way radio device allows the device to determine an expected battery voltage drop for a subsequent transmit event, based on present transmit power settings and battery impedance, and change the power setting for the subsequent transmit event if the battery voltage is likely to drop below a shutdown threshold at the present power setting or if the expected battery voltage drop will cause the battery voltage to be substantially above the shutdown voltage level and the present power setting is below an optimal level.
Abstract:
A system, method, and apparatus for charging primary battery-powered devices and battery-powered accessories tethered to the primary devices are disclosed. The two devices may include batteries of different types having different nominal voltages. A processing unit on the primary device may obtain state-of-charge information and other operating parameters of the batteries and may determine when to provide power to the accessory to charge its battery. The primary device may select its own battery, power provided by a charger to which it is coupled, or conditioned power as the source of charging energy provided to the accessory to charge its battery. Processing units on the two devices may adjust charging parameters to perform energy balancing while the batteries are simultaneously charged, based on operating parameters of the batteries, operating contexts of the devices, a charging prioritization scheme, or a current distribution scheme.
Abstract:
An internal charging system controls charging of a battery used to power an electronic device when an external power source is connected to the device. The internal charging system can charge a battery that has a higher operating voltage than the voltage provided by the external power source. While charging the battery from the external power source, an internal charge controller can operate and inhibit functions of the device to indicate to user that a charging operation is commencing, and to prevent operation of the device when the battery voltage is too low to support such operation.
Abstract:
A portable battery-operated communication device includes a high-speed communication bus, a first high-speed communication processor coupled to the bus and configured for transferring communication signals to a second high-speed communication processor over the bus, and an isolation circuit for the bus with a first terminal coupled to the bus and configured to receive a first communication signal from the first processor via the bus, and a first resistor that is coupled to the first terminal and configured to protect the first terminal from an overcurrent failure condition, in which the isolation circuit is configured to match impendences between the isolation circuit and bus, isolate series inductance associated with the first terminal, protect the first terminal from an overvoltage failure while maintaining signal integrity of the first communication signal, and pass through the first communication signal from the first terminal to a second terminal coupled to the high-speed communication bus.
Abstract:
A method and circuit for mitigating RFI in an electronic device that occurs while the device is in a low power mode utilizes one or more antenna elements in the device to receive RF energy. When the RF energy is sufficiently high that it could affect signal states in the device while in the low power mode, the device transitions from the low power mode to an active mode and begins an RFI mitigation process to ensure signal states and other circuit operations in the device are not changed by the RFI.