Signal modulator

A signal amplifier comprising

• a power stage comprising a first half-bridge and a second half-bridge;
• and
• a modulator adapted to provide a first modulated output for driving the first half-bridge;
• and a second modulated output for driving the second half-bridge,
• wherein the modulator comprises an input stage adapted to receive at least one input signal and a reference signal;
• and an adaptive ramp generator adapted to receive a clock signal having a clock cycle, to provide a ramp signal having a ramp signal profile starting from a minimum level in each clock cycle and to adjust the minimum level in each clock cycle;
• wherein the adaptive ramp generator is adapted to identify the signal having the highest amplitude among the at least one input signal and the reference signal, and to adjust the minimum level such that a peak value of the ramp signal is maintained substantially equal to the signal having the highest amplitude.

A method of modulating at least one input signal, the method comprising

• receiving the at least one input signal,
• receiving a clock signal having a clock cycle,
• receiving a reference signal,
• providing a ramp signal having a profile that starts from a minimum level in each clock cycle,
• identifying the signal having the highest amplitude among the at least one input signal and the reference signal, and
• adjusting the minimum level in each cycle such that a peak value of the ramp signal is maintained substantially equal to the signal having the highest amplitude.