.subckt foo<> GND Vdd en a b _o
M0_ GND en #0 GND nch W=5u L=2u
M1_:pchg Vdd en #0 Vdd pch W=5u L=2u
M2_ #0 a #1 GND nch W=5u L=2u
M3_ #1 b _o GND nch W=5u L=2u
.ends

xbar GND Vdd bar.en bar.a bar.b bar._o foo<>

