Digital DC-DC voltage conversion apparatus and electronic device using the same

A digital DC-DC voltage conversion apparatus, configured to convert an input voltage into an output voltage for a digital core circuit and generate an output current for the digital core circuit, comprising:

• a digital comparator, configured to compare the output voltage and a reference voltage to output a comparison signal when triggered by a clock signal;
• a bi-directional shift register, electrically connected to the digital comparator, and configured to output a plurality of switch control signals based on the comparison signal when triggered by the clock signal;
• a switching current unit, electrically connected to the bi-directional shift register and the digital core circuit, and comprising a plurality of switches, wherein a plurality of first terminals of the plurality of switches are electrically connected to the input voltage, a plurality of second terminals of the plurality of switches are electrically connected to the digital core circuit, a plurality of control terminals of the plurality of switches respectively receive the plurality of switch control signals, and the plurality of switches are configured to make a summed current flowing to the digital core circuit;
• and
• a direct charging path current supply unit, electrically connected to the digital core circuit and the input voltage, comprising a direct charging switch and a direct charging path controller electrically connected to the direct charging switch, wherein a first terminal of the direct charging switch receives the input voltage, a second terminal of the direct charging switch is electrically connected to the digital core circuit, a control terminal of the direct charging switch receives a direct charging switch control signal, and the direct charging path controller generates the direct charging switch control signal to control the direct charging switch to generate a direct charging path current for the digital core circuit, wherein the output current is a sum of the summed current and the direct charging path current.