A power generating circuit

Abstract

The embodiment of the invention discloses a power generation circuit, which comprises a reference core circuit, a voltage detection circuit and a start control circuit, wherein the reference core circuit provides a power signal VO for a load, a voltage control signal V2 is provided for the start control circuit, a first feedback signal V3 of the start control circuit is received, a second feedback signal V4 of the start control circuit is received, a bias input signal V1 is accessed, a power signal VO is provided for the voltage detection circuit, the voltage detection circuit outputs a soft start completion signal V9 to the start control circuit, a switching control signal V5 is accessed to the start control circuit, and a chip enabling signal V8 is accessed to the start control circuit. The embodiment of the invention provides a low-temperature drift power generation circuit with soft start and quick start functions at the same time.

Description

technical field [0001] The invention relates to the technical field of power management, in particular to a power generating circuit. Background technique [0002] In a power management chip, a voltage with a relatively high voltage value is usually used to generate a voltage with a relatively low value and a certain driving capability. In existing schemes, see figure 1 Generally, a typical bandgap reference core circuit is used to generate a voltage V1 with a low-temperature drift coefficient. This voltage is input to the positive terminal of the operational amplifier OP, and the output of the operational amplifier OP is connected to a metal-oxide-semiconductor field with a large number of parallel connections. The effect transistor MOS tube PM1 divides the voltage through the resistors of R1 and R2, and then feeds back to the negative terminal input of the operational amplifier OP. At the same time, an appropriate compensation network is added to the operational amplifier...

AI Technical Summary

Problems solved by technology

[0003] The inventor of this technical solution found in the research process that the compensation network of the power generation circuit in the above-mentioned existing solution is relatively complicated, and consumes a relatively large chip area, which increases the area and cost of the chip; at the same time, in this technical solution , there is no control circuit for controlling the turn-on process of the metal-oxide-semiconductor field-effect transistor MOS transistor PM1, so during the chip start-up process, since the turn-on process of the MOS transistor PM1 is not controlled, the generated voltage VO can easily exceed the predetermined value , the resulting overshoot voltage will cause a voltage surge to the subsequent circuit, and in severe cases, it will cause certain damage to the subsequent circuit

Reducing the parallel connection of MOS tubes PM1 to a very small level can take into account the soft start function and avoid overcharging, but this solution leads to a very slow start-up speed, and after the start-up is completed, the current drive capability of the circuit output will also be weak

[0004] To sum up, the cost of the existing power generation circuit is relatively high, and the application method is limited, so it is difficult to take into account the soft start function and the fast start function at the same time

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