https://easyeda.com/izhadapter/Generator-a64d1e5b932c435c9a9bc4bed174385f Circuit: gooduntitled Doing analysis at TEMP = 27.000000 and TNOM = 27.000000 Warning: singular matrix: check nodes volprobe1 and volprobe1 Note: Starting dynamic gmin stepping Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Warning: singular matrix: check nodes volprobe1 and volprobe1 Warning: Dynamic gmin stepping failed Note: Starting source stepping Warning: singular matrix: check nodes volprobe1 and volprobe1 Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful gmin step Note: One successful source step Warning: singular matrix: check nodes volprobe1 and volprobe1 Warning: singular matrix: check nodes volprobe1 and volprobe1 Warning: source stepping failed Transient solution failed - Last Node Voltages ------------------ Node Last Voltage Previous Iter ---- ------------ ------------- volprobe2 0 0 u1.4_12 0 0 u1.3_8 0 0 xr2_3 0 0 vcc 0 0 xr1_2 0 0 u1.4_11 0 0 r7_1 0 0 u1.1_1 0 0 u1.2_4 0 0 volprobe1 0 0 u1.2_5 0 0 v1#branch 0 0 doAnalyses: iteration limit reached tran simulation(s) aborted Error(parse.c--checkvalid): volprobe1: no such vector. ngspice-26 done