Current control circuit for micro-fluid ejection heaters. In one embodiment, the current through a heater in a micro-fluid ejection device may be monitored and regulated to maintain a particular value or range of values. In such an embodiment, the heater current may be monitored and compared to a reference value. A signal may be induced based upon the divergence of the heater current from the value and the signal may be applied to the logic switch for the monitored heater. The logic switch may regulate the current through the heater based upon the induced signal. As a result of the regulation of the current, the induced signal may dynamically change thereby allowing fast regulation of the heater current.