* 3 stage counter
*
*
.tran 1p 500p
.subckt count 1 4 5 10 11
*
* Two junction SQUID flip-flop
*
b1 3 0 jj1 area=.9
b2 5 0 jj1
c1 4 0 3.5p
r1 3 6 2
r2 5 7 5
l1 3 4 6.3p
l2 4 5 5.7p
l3 1 2 6.3p
l4 2 0 5.7p
l5 6 0 1.2p
l6 7 0 2p
k1 l1 l3 .99
k2 l2 l4 .99
.ends count
*
.subckt pgen 1 4 5 10 11
*
* Two junction SQUID pulse gen
*
b1 3 0 jj1
b2 5 0 jj1
c1 4 0 3.5p
r1 3 6 1.5
r2 5 7 5
l1 3 4 6p
l2 4 5 6p
l3 1 2 6p
l4 2 0 6p
l5 6 0 1.2p
l6 7 0 2p
k1 l1 l3 .99
k2 l2 l4 .99
.ends pgen
*
*
* First stage for SFQ pulse generation only
*
x1 pgen 1 2 3 100 101
x2 count 5 6 7 200 201
x3 count 9 10 11 300 301
x4 count 13 14 15 400 401
x5 count 17 18 19 500 501
*
r1 33 2 50
r2 31 6 50
r3 31 10 50
r4 31 14 50
r5 31 18 50
*
r6 34 1 50
r7 32 1 80
r8 30 5 50
r9 30 9 50
r10 30 13 50
r11 30 17 50
*
r12 3 4 .25
r13 7 8 .25
r14 11 12 .25
r15 15 16 .25
r16 19 20 3.5
l1 4 6 2.0p
l2 8 10 2.0p
l3 12 14 2.0p
l4 16 18 2.0p
l5 20 0 2p
*
r17 3 0 6
*
* flux bias
v1 30 0 pulse(0 5.5m 10p 30p 0p 500p 1500p)
* gate bias
v2 31 0 pulse(0 15.5m 0p 20p 0p 500p 1500p)
*
* flux bias first stage
v3 32 0 pwl (0 0 70p 0
+ 75p  15m 90p  15m 100p -15m 115p -15m 
+ 125p 15m 140p 15m 150p -15m 165p -15m
+ 175p 15m 190p 15m 200p -15m 215p -15m
+ 225p 15m 240p 15m 250p -15m 265p -15m
+ 275p 15m 290p 15m 300p -15m 315p -15m
+ 325p 15m 340p 15m 350p -15m 365p -15m
+ 375p 15m 390p 15m 400p -15m 415p -15m
+ 425p 15m 440p 15m 450p -15m 465p -15m  475p 15m)
*
* gate bias first stage
v4 33 0 pulse(0 15m 0p 20p 0p 500p 1500p) 
*
* flux offset first stage
v5 34 0 pulse(0 4m 10p 30p 0p 500p 1500p)
*
*Nb 1000 A/cm2   area = 30 square microns
.model jj1 jj(rtype=1,cct=1,icon=10m,vg=2.8m,delv=0.08m,
+ icrit=0.3m,r0=100,rn=5.4902,cap=1.14195p)
*
.print nodev 3 0
