Keyboard shortcuts

Press ← or → to navigate between chapters

Press S or / to search in the book

Press ? to show this help

Press Esc to hide this help

vyges-em-ir — power integrity

Part of the Vyges Loom suite. Install once with vyges install loom, then run vyges loom em-ir. It’s also a standalone vyges-em-ir binary on your PATH (the integration contract for flow authors).

vyges-em-ir takes the design’s power-distribution network (PDN) and solves it — reporting IR-drop (supply voltage lost across the grid) and checking electromigration (EM) current limits against a budget. Its dynamic solve is fed by the per-switch energy from vyges-char.

Run it

vyges install loom                                    # one-time: fetch the Loom suite
vyges loom em-ir demo                                 # instant: built-in PDN → IR/EM
vyges loom em-ir run  block.emir -o block.rpt         # analyze → report
vyges loom em-ir run  block.emir --fail-on-violation  # exit 3 if over budget (CI gate)
vyges loom em-ir check block.emir                      # validate the job

See the full CLI reference (generated from --help).

Where it sits

design + PDN + IR/EM budget → IR-drop map + EM check. Turns power integrity from a late, manual sign-off step into a deterministic, CI-gated check. See the data spine.

Digital and analog / mixed-signal

The solve is G·V = I on a generic conductance matrix — there is no standard-cell or Liberty assumption in the physics, only resistors, pads and per-node currents. Besides the DEF path, the engine reads a generic .pdn resistor-network description (used when def: is empty), so a hand-built analog / mixed-signal supply mesh solves exactly as a digital PDN does. The examples/analog_bias/ job is a .pdn mesh with pads and analog op-point load currents standing in for the per-instance digital activity.

vyges loom em-ir run examples/analog_bias/analog_bias.emir   # analog bias mesh → IR-drop + EM

Power-integrity (IR / EM) applies to any grid; the only difference is where the node currents come from — digital switching activity or an analog operating point. Scope here is physical power-integrity; analog functional / timing sign-off is out of scope (that leans on external SPICE / behavioral tools).

Source & releases