Spice to PRS does not respect the PN ratio computation

[nbingham1]

Description

If you take a PRS and convert to SPI then back to PRS, the sizing is all different.

Steps to Reproduce

wchb1b.prs

require driven, stable, noninterfering
~GND<0.1>->weak_Vdd+ [weak]
Vdd<0.1>->weak_GND- [weak]
@weak_GND&R.t<1>|_Reset<3>&L.t<3>&R.e<3>->v3-
@weak_Vdd&~R.t<1>|~_Reset<1>|~L.t<2>&~R.e<2>->v3+
@weak_GND&R.f<1>|_Reset<3>&L.f<3>&R.e<3>->v2-
@weak_Vdd&~R.f<1>|~_Reset<1>|~L.f<2>&~R.e<2>->v2+
_Reset<3>&v0<3>&L.e'1<3>->v1- {v0}
~_Reset<1>|~v0<1>|~L.e'1<1>->v1+
_Reset<3>&v1<3>&L.e'1<3>->v0- {v1}
~_Reset<1>|~v1<1>|~L.e'1<1>->v0+
R.f'1<1>|R.t'1<1>->R.e'1-
~R.t'1<2>&~R.f'1<2>->R.e'1+
v3<1>->R.t-
~v3<1>->R.t+
v2<1>->R.f-
~v2<1>->R.f+
R.f<1>|R.t<1>->L.e-
~R.t<2>&~R.f<2>->L.e+
v1<1>->L.t'1-
~v1<1>->L.t'1+
v0<1>->L.f'1-
~v0<1>->L.f'1+

Commands to execute:

$ lm build -n wchb1b.prs
$ lm unpack wchb1b.spi
$ cat wchb1b_top_ext.prs

wchb1b_top_ext.prs

v0<1>->l.f'1-
~v0<1.64444>->l.f'1+
v1<1>->l.t'1-
~v1<1.64444>->l.t'1+
r.f<1>|r.t<1>->l.e-
~r.t<3.28889>&~r.f<3.28889>->l.e+
r.f'1<1>|r.t'1<1>->r.e'1-
~r.t'1<3.28889>&~r.f'1<3.28889>->r.e'1+
_reset<3>&v1<3>&l.e'1<3>->v0-
~_reset<1.64444>|~v1<1.64444>|~l.e'1<1.64444>->v0+
_reset<3>&v0<3>&l.e'1<3>->v1-
~_reset<1.64444>|~v0<1.64444>|~l.e'1<1.64444>->v1+
v2<1>->r.f-
~v2<1.64444>->r.f+
@weak_gnd&r.f<1>|_reset<3>&l.f<3>&r.e<3>->v2-
@weak_vdd&~r.f<1.64444>|~_reset<1.64444>|~l.f<3.28889>&~r.e<3.28889>->v2+
v3<1>->r.t-
~v3<1.64444>->r.t+
@weak_gnd&r.t<1>|_reset<3>&l.t<3>&r.e<3>->v3-
@weak_vdd&~r.t<1.64444>|~_reset<1.64444>|~l.t<3.28889>&~r.e<3.28889>->v3+
vdd<0.1>->weak_gnd- [weak,after=0]
~gnd<0.163934>->weak_vdd+ [weak,after=0]

Expected Behavior

The two files should match (both sizing, assumptions, and requirements).

Versions

• OS: Ubuntu 24.04.1 LTS
• Loom Version: v0.11.0