High-efficiency regulated voltage-boosting device

A display device comprising:

• a liquid-crystal display having an input receiving a regulated voltage;
• a battery having an output supplying a supply voltage;
• a regulated voltage booster having a plurality of voltage boosting stages coupled in series, a first voltage boosting stage having an input terminal coupled to the output of the battery to receive the supply voltage, and a final voltage boosting stage having an output terminal coupled to the input of the liquid crystal display to provide a second voltage higher than the supply voltage, and each voltage-boosting stage having a select input to selectively activated and deactivated the voltage-boosting stage;
• and
• an automatic-selection circuit having a plurality of select outputs coupled respectively to the select input of the respective voltage-boosting stage for activating a number of the voltage-boosting stages which is correlated to existing operating conditions.

A method for controlling a regulated voltage-boosting device including a charge-pump circuit provided with a plurality of voltage-boosting stages, which can be selectively activated and deactivated the method comprising the steps of:

• supplying a first voltage to said charge-pump circuit;
• and
• generating a second voltage higher than said first voltage;
• and
• activating a number of voltage-boosting stages correlated to existing operating condition.

A regulator device comprising:

• a first voltage supply having an output providing a supply voltage;
• a load circuit having an input;
• a voltage conditioner circuit having a timing input and a plurality of select inputs, a supply input coupled to the output of the first voltage supply to receive the supply voltage and an output couple to the input of the load circuit to provide a regulated voltage;
• a first control circuit coupled between the supply input of the voltage conditioner circuit and the output of the voltage conditioner circuit to provide a timing signal to the timing input of the voltage conditioner circuit, the timing signal having a frequency dependent upon a ratio of the regulated voltage to the supply voltage;
• and
• a second control circuit coupled between the supply input of the voltage conditioner circuit and the output of the voltage conditioner circuit and having a plurality of select outputs being coupled respectively to the plurality of select inputs of the voltage conditioner circuit such that power absorbed by the voltage conditioner is a minimum.

A method of regulating an output voltage of a regulator device, comprising:

• applying an input voltage to the regulator device;
• forming a plurality of intermediate voltages from the input voltage such that an output voltage of the regulator device is formed that is different from the input voltage;
• generating a feedback signal proportional to a voltage difference of the output voltage to a reference voltage and using the feedback signal to determine an intermediate voltage of the plurality of intermediate voltages;
• generating a first set of fractional voltages proportional to the output voltage of the regulator device;
• generating a second set of fractional voltages proportional to the input voltage of the regulator device;
• comparing the first set of fractional voltages to the second set of fractional voltages to form a plurality of select signals;
• and
• selectively generating the intermediate voltages to alter the output voltage of the regulator device based on the plurality of select signals.