| 摘要 |
PROBLEM TO BE SOLVED: To provide a digital-control DC/DC converter that eliminates tradeoff between starting characteristics and transient response characteristics and prevents an increase in circuit scale and complication of a control method. SOLUTION: The digital-control DC/DC converter subjects a switching element to ON/OFF-control by a PWM signal so as to convert an input voltage into a desired output voltage. The converter includes an AD conversion circuit 200 for converting a differential voltage between a detection value of an output voltage Vout and a reference voltage Vref into a digital error signal e[n], a compensation circuit 100 for determining a duty ratio of the PWM signal by the digital error signal, and a digital PWM circuit 300 for generating the PWM signal according to the duty ratio. The compensation circuit 100 includes an arithmetic circuit for performing calculations using different compensation coefficients, a detection circuit for detecting the completion of starting of the output voltage, and a selection circuit for switching the calculation results of the arithmetic circuit according to the detection results of the detection circuit. COPYRIGHT: (C)2011,JPO&INPIT |
