International Business Machines Corporation

C Charles Dishman

Randhir Singh Malik

Jen-Ching Lin

Chu T Chung

Eino Alfred Lindfors

Trung M Nguyen

Ted A Howard

An apparatus, system, and method are disclosed for determining power source failure. A sampling module samples an alternating current power waveform as input to a power supply, at a sampling frequency which is a multiple of a predetermined frequency, to obtain a sampled amplitude at a known point within the predetermined period. A comparison module compares the sampled amplitude to a stored threshold amplitude to obtain a comparison result, corresponding to the known point. An accumulation module accumulates most recent comparison results. A warning module asserts an early power off warning signal if a predetermined number of the most recent comparison results each indicate that the sampled amplitude is smaller in absolute value than the stored threshold amplitude.

Apparatus, system, and method for precise early detection of AC power loss

A positive temperature coefficient device is configured in parallel with a bypass switch and implemented at an input to a switching regulation stage of a switching power supply. A monitoring module determines that a voltage across the regulation switch in the switching power supply is below a predefined threshold voltage for greater than a predefined threshold time period. A control module controls operation of the bypass switch. The control module opens the bypass switch in response to the monitoring module determining that the voltage across the regulation switch is below the predefined threshold voltage for greater than the predefined threshold time period such that substantially all of the current entering the switching regulation stage passes through the PTC device. By causing substantially all of the current to pass through the PTC device, the device will enter a high impedance state thereby preventing smoke and smell from occurring.

Apparatus, system, and method to prevent smoke in a power supply powered by a current limited source

An apparatus, system, and method are disclosed for controlling fan speed in a power supply. The apparatus measures input power to the power supply and measures the output power provided by the power supply over an interval. The apparatus determines values for the input power and output power and, using the two, determines how much power has been dissipated in the power supply. Power dissipation values are associated with particular fan speeds, and the apparatus adjusts the speed of the fan in the power supply based on how much power was dissipated during the interval. Increasing levels of power dissipation increases the fan speed, and decreasing levels of power dissipation decrease the fan speed.

Apparatus, system, and method for improved fan control in a power supply

An apparatus, system, and method are disclosed for fault tolerant cooling in a redundant power system. The apparatus receives power from a common power bus to power one or more power supply fans. The apparatus detects a non-functioning redundant power supply. The apparatus receives a fan control signal within a non-functioning redundant power supply. In addition, the apparatus uses the received fan control signal to synchronize a fan speed of a power supply fan within the non-functioning redundant power supply. The fan speed is synchronized with at least one fan control signal of a power supply fan within a functioning redundant power supply. Thus, the power supply fans of a non-functioning power supply continue to operate and are synchronized with power supply fans in functioning power supplies.

Fault tolerant cooling in a redundant power system

Efficient multiple power outputs are provided by receiving a primary voltage as an input to a bridge module and providing one or more secondary voltages as outputs of the bridge module. The secondary voltages are generated on the secondary side of one or more respective secondary windings of a transformer. The bridge module includes at least one primary complementary pair of switches on the primary winding side of the transformer and a secondary complementary pair of switches on the secondary side of each secondary winding of the transformer. The secondary output voltages are received from the bridge module by one or more output voltage regulation modules. Each output voltage regulation module receives one of the secondary voltages from the bridge module as an input and provides at least one regulated output voltage as an output.

Apparatus, system, and method for a synchronous multiple output power supply

An apparatus, system, and method are disclosed for determining fan rotation direction. A first temperature detection module detects a first temperature at a first location between a fan and a heat generating device. The fan provides cooling for the heat generating device by drawing air from the heat generating device across the first location to the fan when the fan is rotating in a first direction. A second temperature detection module detects a second temperature at a second location where the heat generating device is between the second location and the fan such that heat from the heat generating device is drawn away from the second location when the fan is rotating in the first direction. A temperature comparison module determines if the second temperature is above the first temperature. A fan rotation error module generates a fan rotation error signal if the second temperature is above the first temperature.

Apparatus, system, and method for detecting fan rotation direction in electronic devices

An apparatus, system, and method are disclosed for controlling fan speed. A power sensing module senses input voltage and current of a power supply. The power supply includes one or more stages and regulates at least one output bus. A power calculation module calculates input power from the input voltage and the input current. A temperature sensing module senses an ambient temperature and/or a temperature at a component cooled by a fan. A fan speed calculation module calculates a fan speed signal for the fan. The fan speed signal is a function of the input power calculated by the power calculation module and the sensed temperature sensed by the temperature sensing module for at least a portion of a fan speed range. A fan speed transmission module transmits the fan speed signal to the fan and adjusts a fan speed based on the fan speed signal.

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Raleigh, NC, United States of America

C Charles Dishman