Circuits, methods, and apparatus that provide waveforms having controlled
rise and fall times, as well as accurate peak voltages. One embodiment
provides circuitry for generating a clock signal and a current that are
adjusted for an on-chip capacitance variation. This current is then used
to generate rising and falling edges of a waveform. The clock signal is
used to determine timing of transitions in the waveform. A bandgap or
similar reference voltage is used to determine the peak voltage. This
waveform is then gained using an amplifier circuit, and the output of the
amplifier circuit is used as a programming voltage waveform for an
EE-PROM. One embodiment further uses non-overlapping clocks to drive a
charge pump that is used to generate a supply voltage for the amplifier
circuit that far exceeds the available on-chip supply voltages.