| **.subckt tb_DFF |
| VSS vss GND {vss} |
| VDD vdd vss {vdd} |
| Vref A vss PULSE(0 {vin} 0 1p 1p {Tref/2} {Tref}) DC {vin} AC 0 |
| Vdiv B vss PULSE(0 {vin} 0 1p 1p {1.05*Tref/2} {1.05*Tref}) DC {vin} AC 0 |
| C1 Up vss 10f m=1 |
| x2 Up vdd Q net3 net2 net4 vss net1 pfd_cp_interface_pex_c |
| x1 vdd A Q B vss dff_pfd_pex_c |
| **** begin user architecture code |
| |
| |
| |
| * Parameters |
| .param kp = 0.9 |
| .param vdd = kp*1.8 |
| .param vss = 0.0 |
| .param vin = 1.8 |
| .param fref = 100e6 |
| .param Tref = 1/fref |
| .param C = 1f |
| |
| .options TEMP = 50.0 |
| |
| * Models |
| .lib ~/skywater/skywater-pdk/libraries/sky130_fd_pr_ngspice/latest/models/corners/sky130.lib SS |
| .include ~/caravel_analog_fulgor/xschem/simulations/pfd_cp_interface_pex_c.spice |
| .include ~/caravel_analog_fulgor/xschem/simulations/dff_pfd_pex_c.spice |
| |
| .ic v(net3) = 0.0 |
| .ic v(net4) = 0.0 |
| .ic v(Q) = 0.0 |
| |
| * Data to save |
| .save all |
| |
| * Simulation |
| .control |
| tran 0.1ns 200ns |
| *meas tran Tosc trig v(out) val=0.9 fall=5 targ v(out) val=0.9 fall=15 |
| *meas tran Td1 trig v(out) val=0.9 fall=5 targ v(out1) val=0.9 rise=6 |
| *meas tran Td2 trig v(out1) val=0.9 fall=5 targ v(out2) val=0.9 rise=6 |
| *meas tran Td3 trig v(out2) val=0.9 fall=5 targ v(out) val=0.9 rise=5 |
| *let T = Tosc/10.0 |
| *let f = 1/T |
| *let Td = 1/(2*3*f) |
| *print T f Td |
| write tb_DFF_nor_tran.raw |
| plot v(A)+2 v(B)+2 v(Q) |
| .endc |
| |
| |
| |
| **** end user architecture code |
| **.ends |
| .GLOBAL GND |
| ** flattened .save nodes |
| .end |
