TI and the minuteman related bits: http://www.ti.com/corp/docs/company/history/timeline/defense/1960/docs/62-sp ecial_ics.htm D37D onboard was used in the initial minuteman III missile guidance set (MGS), the NS-20 configuration. It was about 1/4 the size of the D17, still contained a disk and was/is visually less interesting. It has been replaced with the 16-bit missile guidance computer (MGC) in the current NS-50 MGS. The MGS contained the computer, gyro system, amp and guidance set. In the NS-50 configuration the amp is part of the MGC. The MGS is contained in a slice that sits below the reentry system (warhead and associated support systems). Although START [treaty] dramatically reduced the number and capabilities, there are 400+ MMIII ICBMs that remain operational.