Voltage monitoring of switching drivers

A driver apparatus for driving a load comprising:

• a switching driver comprising an output stage configured to switch a first driver output node between different switching voltages to generate a first drive signal for driving the load at the first driver output node;
• and a modulator configured to receive a modulator input signal and to control switching of the output stage based on the modulator input signal;
• and
• a voltage monitor configured to generate an indication of output voltage of the first drive signal, wherein the voltage monitor is configured to receive a first digital signal indicative of the modulator input signal and a second digital signal indicative of modulator operation and to adjust the first digital signal based on the second digital signal to generate said indication of output voltage of the first drive signal.

A circuit comprising:

• a modulator configured to receive a modulator input signal and to generate at least one control signal based on the modulator input signal for controlling switching of an output stage of a switching driver to generate a first drive signal;
• and
• a voltage monitor configured to generate an indication of output voltage of the first drive signal, wherein the voltage monitor is configured to receive a first digital signal indicative of the modulator input signal and an indication of clipping of the modulator and:
• to use the first digital signal to provide the indication of output voltage of the first drive signal when the switching driver is not clipping;
• and
• to generate a synthesised signal to provide the indication of output voltage of the first drive signal when the switching driver is clipping.