US Patent 8981836 Charge pumps with improved latchup characteristics

Some embodiments relate to charge pump regulators to selectively activate a charge pump based not only on the voltage output of the charge pump, but also on a series of wake-up pulses that are delivered at predetermined time intervals and which are delivered independently of the voltage output of the charge pump. Hence, these wake-up pulses prevent extended periods of time in which the charge pump is inactive, thereby helping to prevent latch-up in some situations.