Acoustic logging tool having programmable source waveforms

An acoustic logging tool that comprises:

• a controller;
• a digital-to-analog converter (DAC) that converts a digital waveform from the controller into an analog waveform;
• an acoustic transducer that converts an electrical signal into an acoustic signal;
• a linear driver that receives the analog waveform from the DAC and responsively provides the electrical signal to the acoustic transducer;
• and
• a memory coupled to the controller, wherein the controller generates the digital waveform in accordance with software stored in the memory.

An acoustic logging tool that comprises:

• a controller, the controller adapts an amplitude of a digital waveform to maintain a receive signal within a predetermined dynamic range;
• a digital-to-analog converter (DAC) that converts the digital waveform from the controller into an analog waveform;
• an acoustic transducer that converts an electrical signal into an acoustic signal;
• and
• a linear driver that receives the analog waveform from the DAC and responsively provides the electrical signal to the acoustic transducer.

A logging method that comprises:

• converting a digital waveform into an analog signal;
• providing the analog signal to an acoustic transducer via a linear driver;
• producing an acoustic signal having a waveform that corresponds to the digital waveform;
• receiving acoustic energy that has passed through a formation in response to said producing an acoustic signal;
• and
• adapting an amplitude of the digital waveform to limit a maximum amplitude of the received acoustic energy.

A logging method that comprises:

• storing a digital waveform in a downhole memory;
• retrieving the digital waveform from the downhole memory;
• applying the digital waveform to a digital to analog converter (DAC) that converts the digital waveform into an analog signal;
• providing an electrical signal to an acoustic transducer from a linear driver, wherein the linear driver includes a feedback path to minimize error between a scaled version of the electrical signal and the analog signal.