High-precision constant-current and constant-power self-adaption compensating circuit

Abstract

A high-precision constant-current and constant-power self-adaption compensating circuit comprises a power tube, a current sampling circuit of the power tube, a driving circuit of the power tube, a load feedback circuit, an analog adder, a first comparator, a second comparator and a voltage adjuster. The current sampling circuit of the power tube and the driving circuit of the power tube are connected with the power tube. The voltage adjuster is connected with an output end of the second comparator. A first input end and a second input end of the second comparator are respectively connected with an output end of the current sampling circuit of the power tube and a pre-set current reference voltage source. An output end of the voltage adjustor is connected with a second input end of the analog adder. The voltage adjuster increases or decreases output analog voltage of the voltage adjuster according to an output logic signal of the second comparator. The high-precision constant-current and constant-power self-adaption compensating circuit avoids a pulse width modulation signal error caused by delay of loop transfer, and enables the feedback adjustment amount not to be affected by parameters of application conditions, wherein the parameters of the application conditions include inductance, input voltage, system delay and the like. Meanwhile, the high-precision constant-current and constant-power self-adaption compensation is achieved.

Description

technical field [0001] The invention belongs to the field of electronic power, and relates to a high-precision constant current and constant power self-adaptive compensation circuit. Background technique [0002] With the increasing demand for switching power supplies, the main control chip of the power supply has more stringent requirements for reducing costs, increasing functions, and optimizing performance. For some specific applications, such as notebook adapters, etc., it is required to ensure that the output power has a relatively high consistency under the condition of full-range AC input (90V / 60Hz~264V / 50 Hz); Under the condition of AC input (90V / 60Hz~264V / 50 Hz), the output current is required to ensure high accuracy, and the general deviation must be less than the rated value . Under full-range AC input conditions, whether it is high-precision output power or high-precision output current, it is required that the peak current difference flowing through the prima...

AI Technical Summary

Problems solved by technology

[0021] In order to overcome the technical defects in the prior art that the duty cycle of the power tube switch cannot be adjusted according to various devices and input parameters in specific application situations, and it is difficult to ensure that the output of high-precision constant current and constant power is always maintained, the present invention provides a High precision constant current constant power adaptive compensation circuit

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