正確配置電源并聯(lián)分擔負載電流或風險的系統(tǒng)故障

　　設計師并聯(lián)連接電源，以獲得總輸出電流大于從一個單獨的供應，以及提供冗余，提高可靠性，避免PCB熱問題，提高系統(tǒng)效率。然而，如果工程師沒有正確地配置這些并聯(lián)系統(tǒng)共享負載電流，電源可以關閉之前，所需的電流傳遞，導致系統(tǒng)故障

　　這可能對系統(tǒng)故障只與逐漸增加的電流要求存儲卡的逐步提高，DSP和ASIC，所有這些通常與較低的電源電壓很高的直流電流。這些高性能半導體器件的負載電流也要求非?？斓淖兓?/p>

　　Figure 1： Three power supplies connected in parallel to produce additional current. The total output current is the sum of the output currents of the individual power supplies. （Source： Keysight Technologies）

　　There are several other good reasons to employ a parallel power architecture （Figure 1）：

　　Reliability and Redundancy. Using multiple small power supplies can be more reliable than using a single large power supply. Continuously operating a power supply at maximum load significantly reduces its reliability and shortens its life. Redundancy is important in mission-critical systems such as military or medical applications where failure of one module cannot be allowed to affect the entire system. In situations where a product or system cannot tolerate any downtime， “N + 1 redundant” systems use a number of small supplies where N units are needed to power the load， but a “+1” supply is added for redundancy.

　　Ef?ciency. If the power system must support widely ranging loads， ef?ciency can be optimized by adjusting the number of operating supplies to the load. For example， a DC/DC converter formed by two supplies running at half capacity can have better overall conversion efficiency than a single supply running near full capacity.

　　Thermal Management and Lifespan. Using two or more lower-power modules to produce higher output power also helps to distribute the thermal load， thereby avoiding hot spots on the board. If two supplies source half of the load current， each will get only half as hot as they would not be shouldering the complete load. Spreading the supply heat also puts less thermal stress on components， extending each supply’s lifetime.