FOREWORDStandard Test Interface Language (STIL) (IEEE Std 1450-1999) was developed and approved with an intentionally constrained scope. While DC levels were explicitly excluded from that scope@ it was apparent that DC levels were an area of interest and importance to the STIL user community. The P1450.2 Working Group was formed to address the extension of DC levels to the STIL standard.Three main topics were identified as priorities for the work. These include per-pin reference levels for signal pins (e.g.@ VIH@ VIL@ VOH@ VOL)@ device power supply levels (voltage and current)@ and power sequencing to the device under test. During the course of development@ two other important topics were addressed. These included the capability for switching levels within a period@ and for switching levels between vectors in a pattern.Scope?This standard defines the following:a) Defines structures in STIL for specifying the DC conditions for a DUT. Examples of the DC conditions for device power supplies are DPS setup@ power sequencing to the device@ and power supply limiting/clamping. Examples of the DC conditions for commonly used signal references are VIL@ VIH@ VOL@ VOH@ IOL@ IOH@ VREF@ VClampLow@ and VClampHi.b) Defines structures in STIL such that the DC conditions may be specified either globally@ by pattern burst@ by pattern@ or by vector. c) Defines structures in STIL to allow specification of alternate DC levels. Examples of commonly used alternate levels are VIHH@ VIPP@ and VILL.d) Defines structures in STIL such that the DC levels and alternate levels can be selected within a period@ much the same as timed format events