Patent ID: 7492382

Claim:
A voltage adjusting system for adjusting a driving voltage of a thermal print head (TPH), the voltage adjusting system comprising: a power converter, coupled to a supply voltage, for converting the supply voltage to the driving voltage according to a feedback voltage; a voltage divider, coupled to the power converter, for generating the feedback voltage according to the driving voltage, the voltage divider comprising a first resistive component and a second resistive component, wherein at least a target resistive component of the first resistive component and the second resistive component comprises an electronic variable resistor; an analog-to-digital converter (ADC), coupled to the power converter, for generating a detecting voltage value according to the driving voltage; and a controller, coupled to the ADC and the electronic variable resistor, for controlling the electronic variable resistor to adjust a resistance value of the target resistive component according to the detecting voltage value and a target voltage value.