An inkjet printhead heater chip has an integral voltage regulator that
derives two output voltages from a single chip input voltage. One of the
two output voltages powers control logic circuitry as the other powers FET
drivers. Preferred output voltages include +3.3 volts for the control
logic circuitry and +7.5 volts for the FET drivers. A Vgs of the FET is
about +7.5 volts which enables a FET area width of about 400 microns.
Outputs of the control logic circuitry provide input to the FET drivers. A
resistive heater for ejecting ink couples between a drain of the FET and
the chip input voltage. Voltage regulating capacitors exist on the heater
chip in parallel with the input voltage and each of the output voltages.
Preferred capacitors have a gate oxide and a polysilicon layer overlying a
substrate. Inkjet printers for housing the printheads are also disclosed.
