A dc-dc power supply compensation control circuit based on voltage-controlled delay line

Abstract

The invention discloses a DC-DC power supply compensation control circuit based on a voltage-controlled delay line, which is divided into two parts: a compensation circuit and a delay line. The voltage-controlled output point is connected to the control terminal of the delay line, and the voltage-controlled output point is a feedback voltage. After the output position of the compensation circuit, the external interface of the delay line includes an external clock signal input terminal, a delay signal output terminal, and a control terminal. The input terminal of the delay line is connected to the clock signal, and the voltage control is converted to Time control function. At the same time, the present invention uses the traditional Type III circuit compensation network as the voltage control part to output the control voltage to control the delay of the delay line to ensure that the phase difference between the output of the delay line and the external clock meets the control requirements, that is, the duty cycle meets the current The state requirements make it possible to realize a wide output voltage range without affecting the stability; compared with the traditional control mode, the present invention has the advantages of simple circuit structure, high efficiency, fast transient response and the like.

Description

technical field [0001] The invention belongs to the technical field of integrated circuit design, and specifically designs a DC-DC power supply compensation control circuit based on a voltage-controlled delay line. Background technique [0002] DC / DC converters are voltage converters that effectively output a fixed voltage after converting the input voltage. DC / DC converters are divided into three categories: step-up DC / DC converters, step-down DC / DC converters and buck-boost converters type DC / DC converter. Three types of control can be used according to the needs. The PWM control type has high efficiency and good output voltage ripple and noise; the PFM control type has the characteristics of low power consumption under small loads; the PWM / PFM conversion type implements PFM control when the load is small. And automatically switch to PWM control under heavy load. [0003] DC-DC converters are ubiquitous in power supply equipment, they are used to generate supply voltage ...

AI Technical Summary

Problems solved by technology

[0005] At this stage, there are several problems in the design of high-frequency DC-DC converters: first, when the switching period is reduced to tens of nanoseconds or less, it may cause the PWM controller based on the slope comparator to fail, and additional measures are required to meet high-frequency requirements; secondly, larger comparator delays limit the duty cycle range, which not only affects transient response, but also limits the input / output operating voltage range

Reducing ripple requires high-precision ADC and DPWM, both of which consume a lot of power and increase the complexity of the design

[0006] The traditional solution uses a sawtooth wave and a control voltage to generate a drive signal by comparing it with a comparator, such as figure 1 As shown, when the output signal is disturbed, the feedback signal of the traditional scheme generates a control signal through the path of the compensator module and compares it with the reference signal to obtain a PWM signal. Due to the inherent delay of the comparator, the voltage conversion at a very high switching frequency range will be severely limited

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