Head unit, ultrasonic probe, electronic instrument, and diagnostic device

A head unit for an ultrasonic probe comprising:

• a connecting section configured to electrically connect the head unit to a probe main body of the ultrasonic probe;
• an element chip including an ultrasonic element array having a substrate defining a plurality of openings arranged in an array pattern and a plurality of ultrasonic transducer elements, each of the ultrasonic transducer elements being provided in each of the openings, the element chip being configured to be electrically connected to a processing device of the probe main body through the connecting section;
• and
• a storing section configured to store a gain setting information including a value of gain of a programmable gain amplifier as operation setting information of the processing device to be output to the processing device through the connecting section, the gain setting information being information for setting the gain of the programmable gain amplifier of an analog front-end section that the processing device has to perform signal processing to a signal received from the ultrasonic element array.