A stand-alone DC power network is provided with a DC to DC power converter only, and does not have a converter that will convert AC to DC. In addition, each of the different terminals that provides the DC voltage at different levels will be ranked according to priority as to which ones are the most important to supply the full voltage to, and which ones are of secondary importance in the event there is insufficient power in the system to provide full voltage at the specified current for the different loads. A processor monitors the voltage and current at each of the terminals, and in the event a current is attempted to be drawn from the system which would cause a first priority terminal to be reduced in voltage, the processor will instead reduce the power provided to the second priority terminal and ensure that the first priority terminal does not have a significant reduction in the specified voltage or the amount of current supplied to that terminal at the specified voltage.

This document describes techniques and apparatuses of load allocation for multi-battery devices. In some embodiments, these techniques and apparatuses determine an amount of load power that a multi-battery device consumes to operate. Respective efficiencies at which the device's multiple batteries are capable of providing power are also determined. A respective portion of load power is then drawn from each of the batteries based on their respective efficiencies.

An efficient power supply with fast, wideband response has been disclosed. In one implementation, two switching regulators with different frequency responses are combined to provide wideband, efficient power.

A rechargeable battery jump starting device with a control switch (e.g. rotary control switch) and an optical position sensing switch system to determine the position of the control switch. The optical position sensing switch system includes an optical position sensor using optical coupling to insure the integrity of isolation on the 12V to 24V master switch to allow for a safe and effective operation, and configured so that the microcontroller unit reads the position on the master switch.

A rechargeable battery jump starting device with a control switch (e.g. rotary control switch) and an optical position sensing switch system to determine the position of the control switch. The optical position sensing switch system includes an optical position sensor using optical coupling to insure the integrity of isolation on the 12V to 24V master switch to allow for a safe and effective operation, and configured so that the microcontroller unit reads the position on the master switch.

Aspects extend to methods, systems, and computer program products for balancing input phases across server rack power supplies. A rack manager can monitor individual Alternating Current (AC) phase currents at the rack level. The rack manager knows (or can at least determine) which power supplies are connected to which phase. The rack manager can micro adjust individual PSU output voltages to balance current phases at the rack level. Balancing can occur in response to changed server workloads, hot-unplug of one or more servers, etc. When there is one PSU per server, phase balancing can be accomplished by connecting outputs of power supplies together via busbar or wire. Output voltages of individual power supplies can be adjusted to achieve better phase balancing. Phase imbalance can be corrected by a bus bar or wire carrying enough load to correct phase imbalance.

A circuit design for efficiently transferring significant levels of electrical power with non-inductive circuit elements. Power is transferred using synchronously-switched capacitive elements in such a way that both discharge from the power source and charge transferred to a load (and/or back to the power supply) are supplied as low duration, high-intensity current pulses. The synchronous power transfer alternates between connecting capacitive charge storage elements in parallel and in series so that both step-up and step-down topologies may be readily realized.

A circuit design for efficiently transferring significant levels of electrical power with non-inductive circuit elements. Power is transferred using synchronously-switched capacitive elements in such a way that both discharge from the power source and charge transferred to a load (and/or back to the power supply) are supplied as low duration, high-intensity current pulses. The synchronous power transfer alternates between connecting capacitive charge storage elements in parallel and in series so that both step-up and step-down topologies may be readily realized.

A load driving device includes a switching element, a detector, a determination portion, a controller, and a threshold set portion. The switching element is arranged between a voltage source and a load, or between the load and a ground. The switching element is turned on to supply electric power from the voltage source to the load. The detector detects a current flowing in the switching element. The determination portion compares a detection value of the detector and a threshold value, and determines whether an overcurrent flows in the switching element. The controller controls the switching element based on a determination result of the determination portion. The threshold set portion sets the threshold value to a higher value as voltage of the voltage source is higher. As such, responsiveness of the load driving device is improved and the switching element is protected when a short-circuiting occurs.

A controller for use in a climate control system. The controller, which may be a wireless-enabled thermostat, includes a power stealing circuit configured to steal power from a first load that is in an “on” mode and from a second load that is in an “off” mode. The stealing is performed from the first and second loads at the same time. Sufficient power can be stolen to support substantially constant operation of a transceiver of the controller.