Power supply circuit capable of generating output voltage close to zero and its regulation method

Abstract

The invention relates to a power circuit which can generate an output voltage approaching to zero and an adjustment method thereof. The power circuit comprises a voltage stabilizer, a divider circuit and a gain circuitry; the voltage stabilizer comprises an input terminal, an output terminal and an adjustment terminal, wherein, the input terminal receives an input voltage and the output terminal outputs an output voltage; the divider circuit which is coupled between the output terminal and the ground and uses the output outage to generate a divider voltage; the gain circuitry which is coupled between the adjustment terminal and the divider voltage for receiving the divider voltage generated by the divider circuit to adjust a gain of the output voltage corresponding to a reference voltage. With the invention adopted, the output voltage of the power circuit can be adjusted to be close to zero. The power circuit which can generate the output voltage approaching to zero and the adjustment method thereof have simple technical principle, can be applied to a plurality of reduction voltage stabilizers and provide great convenience, thereby improving the industry greatly.

Description

technical field [0001] This case relates to a power supply circuit and its adjustment method. More particularly, the present invention relates to a power supply circuit capable of generating an output voltage close to zero and its adjustment method. Background technique [0002] Nowadays, the general adjustable voltage power supply circuit (Adjustable Voltage Power Circuit) is as figure 1 As shown, the power supply circuit 1 includes a voltage regulator 10 and a voltage divider circuit 11, wherein the voltage regulator 10 has an input terminal IN, an output terminal OUT, an adjustment terminal ADJ and a ground terminal GND, and the voltage divider circuit 11 It has a first resistor R1 and a second resistor R2, the input terminal IN is used to receive an input voltage Vi, the output terminal OUT is used to output an output voltage Vo, the ground terminal GND is used for grounding, and the first resistor R1 is coupled to the output Between the terminal OUT and the second resi...

AI Technical Summary

Problems solved by technology

That is to say, if the reference voltage Vref is 1.22V, the minimum output voltage Vo will be about 1.22V. In other words, the minimum output voltage Vo is limited by the reference voltage Vref, which is limited in use.

[0009] However, if the power supply circuit is regarded as a small power supply, the above-mentioned fact that the output voltage Vo cannot be adjusted to approach 0V exists, and the use will be limited, which will cause inconvenience during use.

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