The radiation hardened ISL72991RH is a low dropout adjustable negative regulator with an output voltage range of -2.25V to -26V. The device features a 1A output current capability, an adjustable current limit pin (ILIM) and a shutdown pin (SD) for easy on/off control. The device incorporates unique circuitry that enables precision performance over the -55C to +125C temperature range and post-irradiation. Specifications include a reference voltage of -1.25V +40mV/-50mV (max), line regulation of +/-25mV (max), and load regulation of +/-15mV (max). Constructed with the Intersil dielectrically isolated Rad Hard Silicon Gate (RSG) BiCMOS process, these devices are immune to Single Event Latch-up and have been specifically designed to provide highly reliable performance in harsh radiation environments.