DC/DC control circuit based on DCM modulation

Abstract

The invention discloses a DC / DC control circuit based on DCM modulation. The control circuit comprises a clock generation circuit, a DCM modulation circuit, a pulse width generation circuit and / or a gating circuit, wherein the clock generation circuit is used for carrying out frequency multiplication for an input clock signal and then outputting a basic clock signal to the DCM modulation circuit, the pulse width generation circuit under the control of a zero time delay clock is used for outputting a coarse adjustment pulse width signal to the DCM modulation circuit, the DCM modulation circuit is used for outputting a zero time delay clock signal of the basic clock signal to the pulse width generation circuit and generating a time delay clock signal for basic clock signal time delay, the coarse adjustment pulse width signal under the control of the time delay clock signal generates a time delay pulse width signal, and the coarse adjustment pulse width signal and the time delay pulse width signal are inputted into the gating circuit to generate a DC / DC control signal. The control circuit is advantaged in that precise time delay for the basic clock signal is realized through the DCM modulation circuit, which is equivalent to carrying out frequency division for the basic clock signal, duty ratio resolution of the DC / DC control signal is improved under the condition of no change of the basic clock signal, and relatively high accuracy, versatility and applicability are realized.

Description

technical field [0001] The invention belongs to the field of electronic technology, and in particular relates to a DC / DC control circuit. Background technique [0002] Pulse Width Modulation (PWM) DC / DC converters are widely used in portable electronic products such as cameras, video cameras, PDAs, and laptop computers. There are two architectures of PWM DC / DC converters, analog and digital. The product area of ​​the analog architecture is small, low power consumption, occupying the mainstream of the market, but it is very sensitive to noise; while the digital design architecture has good scalability, high stability, and is relatively insensitive to external noise, which can just make up for the lack of analog architecture. shortcoming. From the perspective of the development requirements of DC / DC converters, digital control technology is necessary. In the current design of the digital architecture DC / DC, there is a common disadvantage that the resolution of the duty cycl...

AI Technical Summary

Problems solved by technology

However, this scheme has the following disadvantages: when the basic clock resolution remains unchanged, the modulation accuracy cannot be improved, but the modulation accuracy is low

In addition, the design scheme is more complicated, the design process requirements are higher, and the cost is more expensive

Images