Level shift circuits are disclosed for level shifting an input signal
corresponding to a first voltage domain, to generate a pair of
complementary output signals corresponding to a second, higher-voltage
domain. Snap-back sensitive devices in a discharge circuit for a high
voltage output node are protected, irrespective of the loading on the
output node, and without requiring precise transistor sizing as a
function of the output loading. The snap-back sensitive devices are
protected by a voltage shifter circuit in series with the sensitive
devices, to limit the voltage across the sensitive devices, even for a
high capacitance output node at its highest output voltage. The voltage
shifter circuit is then bypassed to provide for an output low level that
fully reaches the lower power supply rail.