Patent attributes
The liquid discharge head has a heater resistor for heating liquid in a liquid route communicating with a discharge port and generating bubbles and a switch circuit for switching on/off the current to be supplied to the heater resistor. One end of the heater resistor is connected to a power-supply potential, one end of the switch circuit is connected to a ground potential, and the other end of the heater resistor and the other end of the switch circuit are connected to each other. The liquid discharge head has a detection circuit for detecting the voltage of the connection point between the heater resistor and the switch circuit and outputting an output signal when a predetermined change occurs in the voltage, and a switch control circuit for controlling the switching on/off of the switch circuit in accordance with the output signal.
