GTK - TDC analysis Lukas Perktold 14 th April 2010

Progress ► Move to new Design Kit version  Library based -> many issues ► GDS2 based ► Match Measurements to Simulation  Document Errors  Propose Solutions

DK 1.6 – Library Based Issues Copy library and attach it to the new DK version Problems: 1.Missing functions in some PCells (Parameterized Cells) 2.Twelve new DRC Errors (Design Rule Check): -> most of them introduced by modified Layouts 3.LVS mismatch (Layout Versus Schematic) Possible Solutions: 1.Flatten problematic Pcells 2.Flatten problematic Pcells 3.Change Layout + exact copy of design (including PCells, Vias, hierarchy) - compatibility problems ( depends on design )

DK 1.6 – Library Based DRC issues Different Layout for same cell and parameters

DK 1.6 – Library Based LVS issues Special Problem: Assura doesn’t extract subc contact in new DK No LVS match

DK 1.6 – GDS2 based Issues Copy schematics Export and ReImport Layout Problems: 1.(Only) Two new DRC errors 2.LVS [Assura (VLDB)] - EndOfColumn – problems with malformed devices 3.LVS [Assura (VLDB)] - TOP Level - exits with error: unbound devices 4.LVS [Assura (CDL)] - TOP Level - error generating CDL netlist Possible Solutions: 1.Needs to be investigated 2.Replace problematic devices 3.Not investigated - Use LVS [Assurra (CDL)] 4.Needs more investigations – problem with ESD devices + CDL parameters + less compatibility problems - complete flat layout ( no PCells / no vias / etc.); but hierarchy is conserved

CDF Parameter Issues Component Description Format + attached to each cell in library + handles callback functions + defines parameters of a cell + provides section for simulation information (gets updated on creation of a symbol view) + … Inconsistent data in some libraries (not introduces by DK v. 1.6) + cause ‘wrong’ simulation results + introduce errors in CDL netlisting

Solve CDF Parameter Issues Instance Level (Important for simulation) Base Level (Important for CDL netlisting) Watch log window Edit Simulation Information

Summary Library Flow – problems with updated Layout for some devices (introduce new DRC errors) GDS2 Flow – problems with old Layout (LVS has problems to extract devices with old Layout) The move from DK v. 1.4 to DK v. 1.6 is MUCH more problematic as expected No QRC possible on TOP Level without effort Up to EndOfColumn running DRC, LVS (VLDB + CDL) and corrected CDF data

complete move (wish: be able to run QRC on TOP Level) match simulation to measurements (corner simulation) List all errors found through measurements check if the all errors can be explained - Weak performance (e.g. INL) of the TDC for rising edges - Zero dies out for higher frequencies - compare RFN settling values -... write documentation propose solution to errors found Outline