DC linear stabilizeld voltage power supply for main board

Abstract

The power supply includes a feedback circuit composed of amplifier and regulation tube. One input end of amplifier receives a reference voltage, and another input end receives feedback voltage outputted from the regulation tube. One output end of the amplifier outputs a regulation voltage to the regulation tube, and a load is connected to the output end of the regulation tube. The regulation tube is composed of first field effect tube (FET) and second FET connected to each other in parallel that is to say that grid, source and drain poles of the first FET are connected to grid, source and drain poles of the second FET respectively. Two parallel-connected FETs as regulation tube are adopted in DC linear stabilized voltage power supply for main board so as to raise capability of carrying load greatly.

Description

【Technical field】 [0001] The invention relates to a DC linear regulated power supply, in particular to a mainboard DC linear regulated power supply with an improved regulator tube. 【Background technique】 [0002] At present, in the design of the motherboard, the quality of the power supply design is very important. Many low-voltage power supplies are designed with linear regulated power supplies, which can output stable voltages and have low circuit design costs. [0003] Please refer to figure 1 Among them, it is a DC low-voltage linear regulated power supply disclosed in the prior art, which includes a reference voltage generating circuit 1 , a voltage stabilizing circuit 2 and a step-down circuit 3 . The reference voltage generation circuit 1 receives a power supply voltage V such as 3.3V CC , output a stable voltage such as 2.5V as the first input voltage U 1 Provided to the input terminal of the step-down circuit 3; and through the voltage dividing resistors R1 and R...

AI Technical Summary

Problems solved by technology

while the load R L It is connected to the line where the first MOS tube 23 and the second MOS tube 33 are located, then the load capacity of the entire linear regulated power supply depends on the MOS tube with a smaller maximum limit current, thus, this linear regulated power supply The carrying capacity of the load becomes relatively poor due to the above limitations

[0004] In addition, because the current passing through the first MOS transistor 23 and the second MOS transistor 33 is a relatively small current of one of the MOS transistors, it is possible that the maximum load power that the first MOS transistor 23 as a regulator transistor can bear is limited, thereby Potentially reduces component utilization

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