Voltage dividing capacitor circuits, supply modulators and wireless communication devices

A wireless communication device comprising:

• a power amplifier configured to generate a radio frequency (RF) output signal based on a RF input signal;
• a supply modulator configured to generate a plurality of voltages in response to an envelope signal of the RF output signal, each of the plurality of voltages having different voltage levels;
• a switch array configured to select a selected supply voltage from a plurality of voltages based on a received plurality of switch control signals corresponding to the envelope signal, and connect the selected supply voltage to the power amplifier;
• and
• a modem configured to extract an envelope of a baseband signal, and generate the envelope signal based on the extracted envelope,
• wherein the supply modulator includes,
• a DC-DC converter including an inductor connected to a battery voltage;
• first through third power switches connected between the inductor and one of a first voltage node, a second voltage node, and a ground node, respectively, the ground node coupled to a ground voltage;
• a first load capacitor, the first load capacitor connected between the first voltage node and the ground node;
• and
• a second load capacitor, the second load capacitor connected between the second voltage node and the ground node;
• and
• a voltage dividing capacitor circuit including at least two capacitor voltage dividers, the at least two capacitor voltage dividers connected to the first voltage node, the second voltage node, and the ground node,
• wherein the DC-DC converter is configured to, generate a current based on an energy stored in the inductor, and output the current to at least one of the first voltage node and the second voltage node based on power switch control signals, and
• wherein the voltage dividing capacitor circuit is configured to generate the plurality of voltages having different voltage levels based on the current, and output the plurality of voltages to the first voltage node, the second voltage node, and at least a first and second intermediate voltage nodes, the first intermediate voltage node connected between the first voltage node and the second voltage node, and the second intermediate voltage node connected between the second voltage node and the ground node.

A wireless communication device comprising:

• a first power amplifier configured to generate a first radio frequency (RF) output signal based on a first RF input signal;
• a second power amplifier configured to generate a second RF output signal based on a second RF input signal;
• a supply modulator configured to output a plurality of voltages having different voltage levels in response to receiving a first envelope signal of the first RF output signal and a second envelope signal of the second RF output signal, and the supply modulator is configured to output a first average power voltage and a second average power voltage based on an average power signal;
• a first switch array configured to select a first selected supply voltage from the plurality of voltages in response to a plurality of first switch control signals corresponding to the first envelope signal, and output the first selected supply voltage to the first power amplifier;
• a second switch array configured to select a second selected supply voltage from the plurality of voltages in response to a plurality of second switch control signals corresponding to the second envelope signal, and output the second selected supply voltage to the second power amplifier;
• a third switch configured to selectively provide the first average power voltage to the first power amplifier based on a third switch control signal;
• and
• a fourth switch configured to selectively provide the second average power voltage to the second power amplifier based on a fourth switch control signal, and wherein
• the supply modulator includes,
• a DC-DC converter including an inductor connected to a battery voltage,
• first through third power switches connected between the inductor and one of a first voltage node, a second voltage node, and a ground node coupled to a ground voltage, respectively,
• a first load capacitor, the first load capacitor connected between the first voltage node and the ground node,
• a second load capacitor, the second load capacitor connected between the second voltage node and the ground node, and
• a voltage dividing capacitor circuit including at least two capacitor voltage dividers connected to the first voltage node, the second voltage node, and the ground node;
• the DC-DC converter is configured to generate a current based on an energy stored in the inductor, and provide the current to at least one of the first voltage node and the second voltage node based on power switch control signals;
• and
• the voltage dividing capacitor circuit is configured to generate the plurality of voltages having different voltage levels based on the current, and output the plurality of voltages to the first voltage node, the second voltage node, and at least a first and second intermediate voltage nodes, the first intermediate voltage node connected between the first voltage node and the second voltage node, and the second intermediate voltage node connected between the second voltage node and the ground node.