* source BUCK CONVERTER 1
D_D1         0 VX Dbreak 
V_V1         INPUT 0 3.3
R_R1         0 OUTPUT  0.3  
V_V2         CONTROL 0  
+PULSE 0 5 0 1n 1n {Duty/Freq} {1/Freq}
X_S1    CONTROL 0 INPUT VX SCHEMATIC1_S1 
R_Resr         0 N014311  15m  
L_L1         VX OUTPUT  1u  
C_C1         OUTPUT N014311  667u  
.PARAM  duty=0.364 freq=500k

.subckt SCHEMATIC1_S1 1 2 3 4  
S_S1         3 4 1 2 Sbreak
RS_S1         1 2 1G
.ends SCHEMATIC1_S1