An ink jet head, comprising: a nozzle connected to an ink chamber; an actuator configured to change a pressure of the ink chamber; a driver circuit (35, 35A, 35B) configured to supply a drive waveform to the actuator in response to a control signal; a non-volatile memory configured to store information for setting the drive waveform; a first signal line via which a logic power supply voltage is supplied to the driver circuit (35A, 35B); a second signal line via which the control signal is supplied to the driver circuit (35A, 35B); a third signal line via which the logic power supply voltage is supplied to the non-volatile memory; a fourth signal line via which the information stored in the non-volatile memory can be transferred; a first connector circuit that connects the first signal line to the third signal line; and a second connector circuit that connects the second signal line to the fourth signal line, characterized in that the first connector circuit is a diode having an anode connected to the first signal line and a cathode connected to the third signal line, the second connector circuit is a switching element having a power supply terminal and a control terminal, the control terminal being connected to the first signal line, the power supply terminal being connected to the third signal line when the logic power supply voltage from the third signal line is higher than a predetermined threshold value, the switching element electrically connects the second signal line and the fourth signal line, and when the logic power supply voltage from the third signal line is lower than the predetermined threshold value, the switching element does not electrically connect the second signal line and the fourth signal line. a nozzle connected to an ink chamber; an actuator configured to change a pressure of the ink chamber; a driver circuit (35, 35A, 35B) configured to supply a drive waveform to the actuator in response to a control signal; a non-volatile memory configured to store information for setting the drive waveform; a first signal line via which a logic power supply voltage is supplied to the driver circuit (35A, 35B); a second signal line via which the control signal is supplied to the driver circuit (35A, 35B); a third signal line via which the logic power supply voltage is supplied to the non-volatile memory; a fourth signal line via which the information stored in the non-volatile memory can be transferred; a first connector circuit that connects the first signal line to the third signal line; and a second connector circuit that connects the second signal line to the fourth signal line, characterized in that the first connector circuit is a diode having an anode connected to the first signal line and a cathode connected to the third signal line, the second connector circuit is a switching element having a power supply terminal and a control terminal, the control terminal being connected to the first signal line, the power supply terminal being connected to the third signal line when the logic power supply voltage from the third signal line is higher than a predetermined threshold value, the switching element electrically connects the second signal line and the fourth signal line, and when the logic power supply voltage from the third signal line is lower than the predetermined threshold value, the switching element does not electrically connect the second signal line and the fourth signal line.