Element substrate, liquid discharge head, and liquid discharge apparatus

An element substrate including a liquid discharge element, comprising a memory element capable of storing individual information of the element substrate by a write, the memory element being configured to change an impedance value by the write, a plurality of current supply elements capable of supplying a current to the memory element, and a determination unit configured to determine presence/absence of the write based on a voltage generated in the memory element by the current selectively supplied from the plurality of current supply elements, wherein the plurality of current supply elements constitute a part of a current mirror circuit and each supply the current in an amount according to a size ratio to the memory element.