Multiple output power supply

Abstract

The invention discloses a multiple output supply, comprising a transformer provided with at least two output paths, a power control module for controlling the input of the transformer, and a voltage detecting comparison module. The voltage detecting comparison module detects an output voltage of a certain output path in a plurality of output paths except a main output path provided with feedback,and outputs the detecting result to the power control module; the power control module can start up the protection according to the detecting result. The invention further comprises a mutual-inductance element, wherein the mutual-inductance element is in series connected to a detecting output path which is connected with a voltage detecting module and at least one output path of the multiple output supply respectively. The circuit of the invention is very simple, complicated circuits, such as reference source and comparator, are not needed, and the parts that can bring depletion such as resistance are not required.

Description

technical field [0001] The invention relates to a power supply circuit, in particular to a multi-channel output power supply. Background technique [0002] At present, in the multi-output power supplies used in the industry, the main circuit is the output circuit with negative feedback, which has relatively stable performance and high voltage regulation accuracy, while the other output circuits without feedback have poor performance and low voltage regulation accuracy. , so the output with the largest current or the highest importance is generally used as the main output. The remaining small current output circuits are used as auxiliary circuits. At present, the industry's requirements for safety regulations are becoming more and more formal. Each output of a multi-output power supply generally needs to be tested for overload and short circuit. Thin, the wire resistance will be larger, and the PCB trace of the output circuit is generally thinner, and the wire resistance wi...

AI Technical Summary

Problems solved by technology

[0008] When we use the output voltage of an auxiliary circuit that detects multiple outputs for protection, since there may be output circuits with small currents in other auxiliary circuits, when there is a short circuit or overcurrent, the output overcurrent or short circuit current will be caused by the presence of large line resistance and internal resistance. Insufficient to maximize the duty cycle of the power supply, and the transformer cannot pass safety regulations or have safety problems due to the high temperature of this winding, or the existence of other safety problems caused by overheating of PCB traces

[0009] When the input voltage range is wide, the duty cycle of all outputs with the lowest input voltage at full load is greater than the duty cycle of one output in over-current or short-circuit state when the input voltage is higher, and the other output circuits are in light load, using the method of voltage detection can not correctly detect the output overcurrent or short circuit fault

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