Rad-hard LDO regulator for aerospace and satellite power designs

July 10, 2013 // By Graham Prophet
Intersil’s ISL75052SEH is an ultra-low-dropout regulator with lowest shutdown current for longer battery life, with low dropout voltage that maximises efficiency

ISL75052SEH is a radiation hardened, single output LDO specified for an output current of up to 1.5A. Designed for aerospace and satellite power applications, the ISL75052 is the industry’s only SMD-approved LDO that is single event transient (SET) immune. It is high/low dose rate immune via wafer-by-wafer acceptance testing up to 100 krad (Si) and 50 krad (Si), respectively. Operating from an input voltage range of 4.0 V to 13.2 V (14.7 V absolute maximum in-beam), the ISL75052SEH provides output voltages of 0.6 V to 12.7 V. Output voltage is adjustable based on an external resistor divider setting. Typical dropout voltage performance is 225mV at 1.5A, maximising efficiency.

The ultra low dropout performance over temperature and radiation lets users reduce the voltage between the input and out voltage rails, saving significant power. The device’s wide input voltage range of 4 V to 13.2 V allows designers to operate the part over a wide input voltage range, such as 12 V, 5 V or any in-between voltages. Output voltage accuracy of ±2% over radiation and over the military temperature range improves point-of-load (POL) input accuracy tolerance over varying AC/DC application conditions. The device’s 160- µA shutdown current, maximum, lengthens battery life when used in a redundant configuration. A PowerGood output pin is available for easy start-up configuration. It features SET mitigation with no added filters or diodes for LET of 86 MeVcm 2/mg, reducing board space and system cost; wafer-by-wafer radiation guarantee means no upscreening, and high product reliability; and it is a pin-for-pin drop-in to industry-leading solutions. In an 18-lead ceramic flatpack, prototype prices start at $261.99 each.

Intersil, www.intersil.com/products/ISL75052SEH