Precise, low output noise rad-hard voltage references

August 09, 2013 // By Paul Buckley
Intersil has introduced what the company claims is the industry’s most precise and lowest output noise radiation hardened (rad-hard) voltage references.

Available in surface mount packaging, the ISL71090SEH12 and ISL71090SEH25 are intended for the latest generation of telemetry equipment, data acquisition systems and high-end instrumentation products in space and satellite applications.
System designers for modern space applications have had to make performance tradeoffs to meet stringent radiation hardened requirements. Intersil’s family of rad-hard analogue devices use an SOI-based PR40 process providing Single Event Latch-up (SEL) immunity to ensure robust performance in heavy ion environments. This and other Intersil technologies reduce performance compromises in even the most challenging applications.
For example, the ISL71090SEHx voltage references deliver very precise analogue-to-digital conversion, providing initial voltage accuracy of ±0.05%, and ±0.15% over the entire military temperature and radiation exposure ranges. This enables support for highly precise A-to-D conversions.
The ISL71090SEHx family also features a low temperature coefficient of 10 ppm/C and an ultralow output noise specification of 2 µVp-p at 2.5 Vout, and 1 µVp-p at 1.25 Vout.  The low output noise reduces disturbances on components measuring precision signals, meeting the stringent DC precision and low noise requirements of critical high-end instrumentation, data acquisition, and processing applications.
The device family has an input voltage range of 4 to 30V to support multiple system power rails.  SET mitigation uses single output capacitor for LET threshold of 86 2/mg, reducing board space and system cost.  
ISL71090SEHx voltage references (1.25 V and 2.5 V) come in a compact 8-lead flatpack, with prototype prices starting at $126.24 each. The ISL71090SEH12EV1Z and ISL71090SEH25EV1Z evaluation boards offer two voltage options, 1.25 V and 2.5 V respectively, and measure the performance of the ISL71090SEHx voltage references. Each evaluation board is available for $88.24.