Multiplexed, Rad Hard ADC

The proposed part is a rad-hard, 16-input, 14-bit ADC, with aggregate speed of 200 MSPS. The 16 inputs are sampled individually and can be configured as 16 single-ended inputs or 8 differential inputs. The ADC provides 14 data outputs, a data-ready signal, and an over-range indicator. The digital outputs of the ADC are CMOS low-voltage differential signal (LVDS) outputs. The part will be fabricated using Texas Instruments' BiCom3X, a SOI process with CMOS and complementary SiGe bipolar transistors. SiGe bipolar transistors typically have very high total dose hardness, and we are not aware of an ELDRS problem. The SOI wells prevent latch-up and restrict the silicon volume that can produce photocurrents from either ionizing dose rates or single event strikes. Our designers, Bill Poland, Jim Swonger, Wayne Dietrich and John Branning, have designed over 140 ASICs, many of them rad-hard. They worked together on a 14-bit rad-hard ADC, on which the proposed part is based. Nu-Trek is an emerging suppler of rad-hard parts, with four parts coming on sale in 2008. The Nu-Det has already been inserted into the MKV and NGIMU. The Clam/NED is slated for insertion in the Army's FCS.