diff --git a/Prelayout/DNL_LSB.png b/Prelayout/DNL_LSB.png
new file mode 100644
index 0000000..5bf1871
--- /dev/null
+++ b/Prelayout/DNL_LSB.png
Binary files differ
diff --git a/Prelayout/INL_LSB.png b/Prelayout/INL_LSB.png
new file mode 100644
index 0000000..642e7b1
--- /dev/null
+++ b/Prelayout/INL_LSB.png
Binary files differ
diff --git a/Prelayout/Prelayout_dnl_inl_data.xlsx b/Prelayout/Prelayout_dnl_inl_data.xlsx
new file mode 100644
index 0000000..7668c4d
--- /dev/null
+++ b/Prelayout/Prelayout_dnl_inl_data.xlsx
Binary files differ
diff --git a/Prelayout/my_10bitdac.spice b/Prelayout/my_10bitdac.spice
new file mode 100644
index 0000000..a87b914
--- /dev/null
+++ b/Prelayout/my_10bitdac.spice
@@ -0,0 +1,239 @@
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+**.subckt 10bitdac_tb
+x1 x1_inp1 x1_inp2 x1_vdd 0 x1_d0 x1_d1 x1_out_v x1_d2 x1_d3 x1_d4 x1_d5 x1_d6 x1_d7 x1_d8 x1_d9 10bitdac
+V1 x1_vdd 0 dc 3.3V
+V2 x1_d0 0 PULSE 0 1.8 0 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0 1p 1p 10u 20u
+V4 x1_inp2 0 dc 0
+V5 x1_inp1 0 dc 3.3V
+V6 x1_d2 0 PULSE 0 1.8 0 1p 1p 20u 40u
+V7 x1_d3 0 PULSE 0 1.8 0 1p 1p 40u 80u
+V8 x1_d4 0 PULSE 0 1.8 0 1p 1p 80u 160u
+V9 x1_d5 0 PULSE 0 1.8 0 1p 1p 160u 320u
+V10 x1_d6 0 PULSE 0 1.8 0 1p 1p 320u 640u
+V11 x1_d7 0 PULSE 0 1.8 0 1p 1p 640u 1280u
+V12 x1_d8 0 PULSE 0 1.8 0 1p 1p 1280u 2560u
+V13 x1_d9 0 PULSE 0 1.8 0 1p 1p 2560u 5120u
+C1 x1_out_v 0 500f
+**.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/10bitdac.sym # of pins=15
+
+.subckt 10bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6 d7 d8 d9
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+*.ipin d7
+*.ipin d8
+*.ipin d9
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d9 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 d6 d7 d8 9bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 d6 d7 d8 9bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/9bitdac.sym # of pins=14
+
+.subckt 9bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6 d7 d8
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+*.ipin d7
+*.ipin d8
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d8 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 d6 d7 8bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 d6 d7 8bitdac
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/8bitdac.sym # of pins=13
+
+.subckt 8bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6 d7
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+*.ipin d7
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d7 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 d6 7bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 d6 7bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/7bitdac.sym # of pins=12
+
+.subckt 7bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d6 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 6bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 6bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/6bitdac.sym # of pins=11
+
+
+.subckt 6bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d5 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d4 d1 x1_out_v d2 d3 5bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d4 d1 x2_out_v d2 d3 5bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/5bitdac.sym # of pins=10
+
+.subckt 5bitdac inp1 inp2 vdd gnda d0 d4 d1 out_v d2 d3
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d4
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+R1 x1_vref5 x2_vref1 250 
+x3 x1_out_v vdd out_v d4 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d3 d1 x1_out_v d2 4bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d3 d1 x2_out_v d2 4bitdac
+.ends
+
+
+.subckt 4bitdac inp1 inp2 vdd gnda d0 d3 d1 out_v d2
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d3
+*.ipin d1
+*.opin out_v
+*.ipin d2
+R1 x2_vref1 x1_vref5 250
+x3 x1_out_v vdd out_v d3 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d2 d1 x1_out_v 3bitdac
+x2 x2_vref1 inp2 vdd  gnda d0 d2 d1 x2_out_v 3bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/3bitdac.sym # of pins=8
+
+
+.subckt 3bitdac inp1 inp2 vdd gnda d0 d2 d1 out_v
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d2
+*.ipin d1
+*.opin out_v
+R1 x1_vref5 x2_vref1 250 
+x1 vdd inp1 gnda x1_out_v d1 d0 x1_vref5 2bitdac
+x2 vdd x2_vref1 gnda x2_out_v d1 d0 inp2 2bitdac
+x3 x1_out_v vdd out_v d2 gnda x2_out_v TG2
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2 
+
+.ends
+
+.tran 2u 5120u
+.control
+run 
+plot x1_d0 x1_d1 x1_d2 x1_d3 x1_d4 x1_d5 x1_d6 x1_d7 x1_d8 x1_d9 
+plot x1_out_v
+
+.endc
+.end
diff --git a/Prelayout/my_2bitdac.spice b/Prelayout/my_2bitdac.spice
new file mode 100644
index 0000000..a4c1b91
--- /dev/null
+++ b/Prelayout/my_2bitdac.spice
@@ -0,0 +1,65 @@
+
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+**.subckt 2bitdac_tb
+x1 x1_vdd x1_vref1 0 x1_out_v x1_d1 x1_d0 x1_vref5 2bitdac
+V1 x1_vdd 0 dc 3.3
+V2 x1_d0 0 PULSE 0 1.8 0ns 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0ns 1p 1p 10u 20u
+V4 x1_vref5 0 dc 0.1
+V5 x1_vref1 0 dc 3.3V
+**.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500 
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+.ends
+
+.tran 1n 20u
+.control
+run 
+plot x1_d0 x1_d1 x1_out_v
+.endc
+.end
+
+
+
diff --git a/Prelayout/my_3bitdac.spice b/Prelayout/my_3bitdac.spice
new file mode 100644
index 0000000..abefd9f
--- /dev/null
+++ b/Prelayout/my_3bitdac.spice
@@ -0,0 +1,85 @@
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+**.subckt 3bitdac_tb
+x1 x1_inp1 x1_inp2 x1_vdd 0 x1_d0 x1_d2 x1_d1 x1_out_v 3bitdac
+V1 x1_vdd 0 dc 3.3
+V2 x1_d0 0 PULSE 0 1.8 0ns 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0ns 1p 1p 10u 20u
+V4 x1_inp2 0 dc 0
+V5 x1_inp1 0 dc 3.3V
+V6 x1_d2 0 PULSE 0 1.8 0ns 1p 1p 20u 40u
+
+**.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/3bitdac.sym # of pins=8
+
+
+.subckt 3bitdac inp1 inp2 vdd gnda d0 d2 d1 out_v
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d2
+*.ipin d1
+*.opin out_v
+R1 x1_vref5 x2_vref1 250 
+x1 vdd inp1 gnda x1_out_v d1 d0 x1_vref5 2bitdac
+x2 vdd x2_vref1 gnda x2_out_v d1 d0 inp2 2bitdac
+x3 x1_out_v vdd out_v d2 gnda x2_out_v TG2
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500 
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=06 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+.ends
+
+.tran 1n 40u
+.control
+run 
+plot x1_d0 x1_d1 x1_d2 x1_out_v
+
+.endc
+.end
+
+
+
diff --git a/Prelayout/my_4bitdac.spice b/Prelayout/my_4bitdac.spice
new file mode 100644
index 0000000..091624a
--- /dev/null
+++ b/Prelayout/my_4bitdac.spice
@@ -0,0 +1,103 @@
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+**.subckt 4bitdac_tb
+x1 x1_inp1 x1_inp2 x1_vdd 0 x1_d0 x1_d3 x1_d1 x1_out_v x1_d2 4bitdac
+V1 x1_vdd 0 dc 3.3
+V2 x1_d0 0 PULSE 0 1.8 0ns 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0ns 1p 1p 10u 20u
+V4 x1_inp2 0 dc 0
+V5 x1_inp1 0 dc 3.3V
+V6 x1_d2 0 PULSE 0 1.8 0ns 1p 1p 20u 40u
+V7 x1_d3 0 PULSE 0 1.8 0ns 1p 1p 40u 80u
+
+**.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/4bitdac.sym # of pins=9
+
+
+
+.subckt 4bitdac inp1 inp2 vdd gnda d0 d3 d1 out_v d2
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d3
+*.ipin d1
+*.opin out_v
+*.ipin d2
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d3 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d2 d1 x1_out_v 3bitdac
+x2 x2_vref1 inp2 vdd  gnda d0 d2 d1 x2_out_v 3bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/3bitdac.sym # of pins=8
+
+
+.subckt 3bitdac inp1 inp2 vdd gnda d0 d2 d1 out_v
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d2
+*.ipin d1
+*.opin out_v
+R1 x1_vref5 x2_vref1 250 
+x1 vdd inp1 gnda x1_out_v d1 d0 x1_vref5 2bitdac
+x2 vdd x2_vref1 gnda x2_out_v d1 d0 inp2 2bitdac
+x3 x1_out_v vdd out_v d2 gnda x2_out_v TG2
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2 
+
+.ends
+
+.tran 1n 80u
+.control
+run 
+plot x1_d0 x1_d1 x1_d2 x1_d3 x1_out_v
+
+.endc
+.end
diff --git a/Prelayout/my_5bitdac.spice b/Prelayout/my_5bitdac.spice
new file mode 100644
index 0000000..8920835
--- /dev/null
+++ b/Prelayout/my_5bitdac.spice
@@ -0,0 +1,123 @@
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+**.subckt 5bitdac_tb
+
+x1 x1_inp1 x1_inp2 x1_vdd 0 x1_d0 x1_d4 x1_d1 x1_out_v x1_d2 x1_d3 5bitdac
+
+V1 x1_vdd 0 dc 3.3
+V2 x1_d0 0 PULSE 0 1.8 0ns 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0ns 1p 1p 10u 20u
+V4 x1_inp2 0 dc 0
+V5 x1_inp1 0 dc 3.3V
+V6 x1_d2 0 PULSE 0 1.8 0ns 1p 1p 20u 40u
+V7 x1_d3 0 PULSE 0 1.8 0ns 1p 1p 40u 80u
+V8 x1_d4 0 PULSE 0 1.8 0ns 1p 1p 80u 160u
+**.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/5bitdac.sym # of pins=10
+
+
+.subckt 5bitdac inp1 inp2 vdd gnda d0 d4 d1 out_v d2 d3
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d4
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+R1 x1_vref5 x2_vref1 250 
+x3 x1_out_v vdd out_v d4 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d3 d1 x1_out_v d2 4bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d3 d1 x2_out_v d2 4bitdac
+.ends
+
+
+.subckt 4bitdac inp1 inp2 vdd gnda d0 d3 d1 out_v d2
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d3
+*.ipin d1
+*.opin out_v
+*.ipin d2
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d3 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d2 d1 x1_out_v 3bitdac
+x2 x2_vref1 inp2 vdd  gnda d0 d2 d1 x2_out_v 3bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/3bitdac.sym # of pins=8
+
+
+.subckt 3bitdac inp1 inp2 vdd gnda d0 d2 d1 out_v
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d2
+*.ipin d1
+*.opin out_v
+R1 x1_vref5 x2_vref1 250 
+x1 vdd inp1 gnda x1_out_v d1 d0 x1_vref5 2bitdac
+x2 vdd x2_vref1 gnda x2_out_v d1 d0 inp2 2bitdac
+x3 x1_out_v vdd out_v d2 gnda x2_out_v TG2
+C1 x1_out_v 0 1p
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+.ends
+
+.tran 0.5u 160u
+.control
+run 
+plot x1_d0 x1_d1 x1_d2 x1_d3 x1_d4 x1_out_v
+
+.endc
+.end
diff --git a/Prelayout/my_6bitdac.spice b/Prelayout/my_6bitdac.spice
new file mode 100644
index 0000000..8a02ba2
--- /dev/null
+++ b/Prelayout/my_6bitdac.spice
@@ -0,0 +1,141 @@
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+**.subckt 6bitdac_tb
+x1 x1_inp1 x1_inp2 x1_vdd 0 x1_d0 x1_d1 x1_out_v x1_d2 x1_d3 x1_d4 x1_d5 6bitdac
+V1 x1_vdd 0 dc 3.3
+V2 x1_d0 0 PULSE 0 1.8 0ns 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0ns 1p 1p 10u 20u
+V4 x1_inp2 0 dc 0
+V5 x1_inp1 0 dc 3.3V
+V6 x1_d2 0 PULSE 0 1.8 0ns 1p 1p 20u 40u
+V7 x1_d3 0 PULSE 0 1.8 0ns 1p 1p 40u 80u
+V8 x1_d4 0 PULSE 0 1.8 0ns 1p 1p 80u 160u
+V9 x1_d5 0 PULSE 0 1.8 0ns 1p 1p 160u 320u
+**.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/6bitdac.sym # of pins=11
+
+
+.subckt 6bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d5 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d4 d1 x1_out_v d2 d3 5bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d4 d1 x2_out_v d2 d3 5bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/5bitdac.sym # of pins=10
+
+.subckt 5bitdac inp1 inp2 vdd gnda d0 d4 d1 out_v d2 d3
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d4
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+R1 x1_vref5 x2_vref1 250 
+x3 x1_out_v vdd out_v d4 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d3 d1 x1_out_v d2 4bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d3 d1 x2_out_v d2 4bitdac
+.ends
+
+
+.subckt 4bitdac inp1 inp2 vdd gnda d0 d3 d1 out_v d2
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d3
+*.ipin d1
+*.opin out_v
+*.ipin d2
+R1 x2_vref1 x1_vref5 250
+x3 x1_out_v vdd out_v d3 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d2 d1 x1_out_v 3bitdac
+x2 x2_vref1 inp2 vdd  gnda d0 d2 d1 x2_out_v 3bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/3bitdac.sym # of pins=8
+
+
+.subckt 3bitdac inp1 inp2 vdd gnda d0 d2 d1 out_v
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d2
+*.ipin d1
+*.opin out_v
+R1 x1_vref5 x2_vref1 250 
+x1 vdd inp1 gnda x1_out_v d1 d0 x1_vref5 2bitdac
+x2 vdd x2_vref1 gnda x2_out_v d1 d0 inp2 2bitdac
+x3 x1_out_v vdd out_v d2 gnda x2_out_v TG2
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+.ends
+
+.tran 0.5u 320u
+.control
+run 
+plot x1_d0 x1_d1 x1_d2 x1_d3 x1_d4 x1_d5 x1_out_v
+
+.endc
+.end
diff --git a/Prelayout/my_7bitdac.spice b/Prelayout/my_7bitdac.spice
new file mode 100644
index 0000000..8a95741
--- /dev/null
+++ b/Prelayout/my_7bitdac.spice
@@ -0,0 +1,163 @@
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+**.subckt 7bitdac_tb
+x1 x1_inp1 x1_inp2 x1_vdd 0 x1_d0 x1_d1 x1_out_v x1_d2 x1_d3 x1_d4 x1_d5 x1_d6 7bitdac
+
+V1 x1_vdd 0 dc 3.3
+V2 x1_d0 0 PULSE 0 1.8 0 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0 1p 1p 10u 20u
+V4 x1_inp2 0 dc 0
+V5 x1_inp1 0 dc 3.3V
+V6 x1_d2 0 PULSE 0 1.8 0 1p 1p 20u 40u
+V7 x1_d3 0 PULSE 0 1.8 0 1p 1p 40u 80u
+V8 x1_d4 0 PULSE 0 1.8 0 1p 1p 80u 160u
+V9 x1_d5 0 PULSE 0 1.8 0 1p 1p 160u 320u
+V10 x1_d6 0 PULSE 0 1.8 0 1p 1p 320u 640u
+**.ends
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/7bitdac.sym # of pins=12
+
+.subckt 7bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d6 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 6bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 6bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/6bitdac.sym # of pins=11
+
+
+.subckt 6bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d5 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d4 d1 x1_out_v d2 d3 5bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d4 d1 x2_out_v d2 d3 5bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/5bitdac.sym # of pins=10
+
+.subckt 5bitdac inp1 inp2 vdd gnda d0 d4 d1 out_v d2 d3
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d4
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+R1 x1_vref5 x2_vref1 250 
+x3 x1_out_v vdd out_v d4 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d3 d1 x1_out_v d2 4bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d3 d1 x2_out_v d2 4bitdac
+.ends
+
+
+.subckt 4bitdac inp1 inp2 vdd gnda d0 d3 d1 out_v d2
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d3
+*.ipin d1
+*.opin out_v
+*.ipin d2
+R1 x2_vref1 x1_vref5 250
+x3 x1_out_v vdd out_v d3 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d2 d1 x1_out_v 3bitdac
+x2 x2_vref1 inp2 vdd  gnda d0 d2 d1 x2_out_v 3bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/3bitdac.sym # of pins=8
+
+
+.subckt 3bitdac inp1 inp2 vdd gnda d0 d2 d1 out_v
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d2
+*.ipin d1
+*.opin out_v
+R1 x1_vref5 x2_vref1 250 
+x1 vdd inp1 gnda x1_out_v d1 d0 x1_vref5 2bitdac
+x2 vdd x2_vref1 gnda x2_out_v d1 d0 inp2 2bitdac
+x3 x1_out_v vdd out_v d2 gnda x2_out_v TG2
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+.ends
+
+.tran 2u 640u
+.control
+run 
+plot x1_d0 x1_d1 x1_d2 x1_d3 x1_d4 x1_d5 x1_d6 x1_out_v
+
+.endc
+.end
diff --git a/Prelayout/my_8bitdac.spice b/Prelayout/my_8bitdac.spice
new file mode 100644
index 0000000..ef21923
--- /dev/null
+++ b/Prelayout/my_8bitdac.spice
@@ -0,0 +1,199 @@
+*Model Description
+.param temp=27
+
+
+*Including sky130 library files
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+.options wnflag=1
+
+
+*Netlist Description
+
+
+
+**.subckt 8bitdac_tb
+x1 x1_inp1 x1_inp2 x1_vdd 0 x1_d0 x1_d1 x1_out_v x1_d2 x1_d3 x1_d4 x1_d5 x1_d6 x1_d7 8bitdac
+V1 x1_vdd 0 dc 3.3V
+V2 x1_d0 0 PULSE 0 1.8 0 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0 1p 1p 10u 20u
+V4 x1_inp2 0 dc 0
+V5 x1_inp1 0 dc 3.3V
+V6 x1_d2 0 PULSE 0 1.8 0 1p 1p 20u 40u
+V7 x1_d3 0 PULSE 0 1.8 0 1p 1p 40u 80u
+V8 x1_d4 0 PULSE 0 1.8 0 1p 1p 80u 160u
+V9 x1_d5 0 PULSE 0 1.8 0 1p 1p 160u 320u
+V10 x1_d6 0 PULSE 0 1.8 0 1p 1p 320u 640u
+V11 x1_d7 0 PULSE 0 1.8 0 1p 1p 640u 1280u
+C1 x1_out_v 0 100f
+**.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/8bitdac.sym # of pins=13
+
+.subckt 8bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6 d7
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+*.ipin d7
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d7 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 d6 7bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 d6 7bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/7bitdac.sym # of pins=12
+
+.subckt 7bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d6 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 6bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 6bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/6bitdac.sym # of pins=11
+
+
+.subckt 6bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d5 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d4 d1 x1_out_v d2 d3 5bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d4 d1 x2_out_v d2 d3 5bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/5bitdac.sym # of pins=10
+
+.subckt 5bitdac inp1 inp2 vdd gnda d0 d4 d1 out_v d2 d3
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d4
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+R1 x1_vref5 x2_vref1 250 
+x3 x1_out_v vdd out_v d4 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d3 d1 x1_out_v d2 4bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d3 d1 x2_out_v d2 4bitdac
+.ends
+
+
+.subckt 4bitdac inp1 inp2 vdd gnda d0 d3 d1 out_v d2
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d3
+*.ipin d1
+*.opin out_v
+*.ipin d2
+R1 x2_vref1 x1_vref5 250
+x3 x1_out_v vdd out_v d3 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d2 d1 x1_out_v 3bitdac
+x2 x2_vref1 inp2 vdd  gnda d0 d2 d1 x2_out_v 3bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/3bitdac.sym # of pins=8
+
+
+.subckt 3bitdac inp1 inp2 vdd gnda d0 d2 d1 out_v
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d2
+*.ipin d1
+*.opin out_v
+R1 x1_vref5 x2_vref1 250 
+x1 vdd inp1 gnda x1_out_v d1 d0 x1_vref5 2bitdac
+x2 vdd x2_vref1 gnda x2_out_v d1 d0 inp2 2bitdac
+x3 x1_out_v vdd out_v d2 gnda x2_out_v TG2
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2 
+.ends
+
+.tran 2u 1280u
+.control
+run 
+plot x1_d0 x1_d1 x1_d2 x1_d3 x1_d4 x1_d5 x1_d6 x1_d7 
+plot x1_out_v
+
+.endc
+.end
diff --git a/Prelayout/my_9bitdac.spice b/Prelayout/my_9bitdac.spice
new file mode 100644
index 0000000..4747708
--- /dev/null
+++ b/Prelayout/my_9bitdac.spice
@@ -0,0 +1,213 @@
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+**.subckt 9bitdac_tb
+x1 x1_inp1 x1_inp2 x1_vdd 0 x1_d0 x1_d1 x1_out_v x1_d2 x1_d3 x1_d4 x1_d5 x1_d6 x1_d7 x1_d8 9bitdac
+V1 x1_vdd 0 dc 3.3V
+V2 x1_d0 0 PULSE 0 1.8 0 1p 1p 5u 10u
+V3 x1_d1 0 PULSE 0 1.8 0 1p 1p 10u 20u
+V4 x1_inp2 0 dc 0
+V5 x1_inp1 0 dc 3.3V
+V6 x1_d2 0 PULSE 0 1.8 0 1p 1p 20u 40u
+V7 x1_d3 0 PULSE 0 1.8 0 1p 1p 40u 80u
+V8 x1_d4 0 PULSE 0 1.8 0 1p 1p 80u 160u
+V9 x1_d5 0 PULSE 0 1.8 0 1p 1p 160u 320u
+V10 x1_d6 0 PULSE 0 1.8 0 1p 1p 320u 640u
+V11 x1_d7 0 PULSE 0 1.8 0 1p 1p 640u 1280u
+V12 x1_d8 0 PULSE 0 1.8 0 1p 1p 1280u 2560u
+C1 x1_out_v 0 500f
+**.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/9bitdac.sym # of pins=14
+
+.subckt 9bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6 d7 d8
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+*.ipin d7
+*.ipin d8
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d8 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 d6 d7 8bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 d6 d7 8bitdac
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/8bitdac.sym # of pins=13
+
+.subckt 8bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6 d7
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+*.ipin d7
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d7 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 d6 7bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 d6 7bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/7bitdac.sym # of pins=12
+.subckt 7bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5 d6
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+*.ipin d6
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d6 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d1 x1_out_v d2 d3 d4 d5 6bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d1 x2_out_v d2 d3 d4 d5 6bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/6bitdac.sym # of pins=11
+
+
+.subckt 6bitdac inp1 inp2 vdd gnda d0 d1 out_v d2 d3 d4 d5
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+*.ipin d4
+*.ipin d5
+R1 x1_vref5 x2_vref1 250
+x3 x1_out_v vdd out_v d5 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d4 d1 x1_out_v d2 d3 5bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d4 d1 x2_out_v d2 d3 5bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/5bitdac.sym # of pins=10
+
+.subckt 5bitdac inp1 inp2 vdd gnda d0 d4 d1 out_v d2 d3
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d4
+*.ipin d1
+*.opin out_v
+*.ipin d2
+*.ipin d3
+R1 x1_vref5 x2_vref1 250 
+x3 x1_out_v vdd out_v d4 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d3 d1 x1_out_v d2 4bitdac
+x2 x2_vref1 inp2 vdd gnda d0 d3 d1 x2_out_v d2 4bitdac
+.ends
+
+
+.subckt 4bitdac inp1 inp2 vdd gnda d0 d3 d1 out_v d2
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d3
+*.ipin d1
+*.opin out_v
+*.ipin d2
+R1 x2_vref1 x1_vref5 250
+x3 x1_out_v vdd out_v d3 gnda x2_out_v TG2
+x1 inp1 x1_vref5 vdd gnda d0 d2 d1 x1_out_v 3bitdac
+x2 x2_vref1 inp2 vdd  gnda d0 d2 d1 x2_out_v 3bitdac
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/3bitdac.sym # of pins=8
+
+
+.subckt 3bitdac inp1 inp2 vdd gnda d0 d2 d1 out_v
+*.ipin inp1
+*.ipin inp2
+*.iopin vdd
+*.iopin gnda
+*.ipin d0
+*.ipin d2
+*.ipin d1
+*.opin out_v
+R1 x1_vref5 x2_vref1 250 
+x1 vdd inp1 gnda x1_out_v d1 d0 x1_vref5 2bitdac
+x2 vdd x2_vref1 gnda x2_out_v d1 d0 inp2 2bitdac
+x3 x1_out_v vdd out_v d2 gnda x2_out_v TG2
+.ends
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/2bitdac.sym # of pins=7
+
+.subckt 2bitdac  vdd vref1 gnda out_v d1 d0 vref5
+*.ipin vref1
+*.ipin vref5
+*.ipin d0
+*.ipin d1
+*.iopin vdd
+*.iopin gnda
+*.opin out_v
+x1 x1_inp1 vdd x1_vout d0 gnda x1_inp2 TG2
+x2 x2_inp1 vdd x2_vout d0 gnda vref5 TG2
+x3 x1_vout vdd out_v d1 gnda x2_vout TG2
+R1 x1_inp1 vref1 500
+R2 x1_inp2 x1_inp1 500
+R3 x2_inp1 x1_inp2 500
+R4 vref5 x2_inp1 250
+.ends
+
+
+* expanding   symbol:  /home/harshitha/Desktop/xschem/xschem_library/TG2.sym # of pins=6
+
+.subckt TG2  inp1 vdd vout din 0 inp2
+*.ipin inp1
+*.ipin inp2
+*.opin vout
+*.ipin din
+*.iopin vdd
+*.iopin gnda
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2 
+
+.ends
+
+.tran 2u 2560u
+.control
+run 
+plot x1_d0 x1_d1 x1_d2 x1_d3 x1_d4 x1_d5 x1_d6 x1_d7 x1_d8 
+plot x1_out_v
+
+.endc
+.end
+
diff --git a/Prelayout/switch.spice b/Prelayout/switch.spice
new file mode 100644
index 0000000..41951e1
--- /dev/null
+++ b/Prelayout/switch.spice
@@ -0,0 +1,33 @@
+
+.lib "sky130_fd_pr/models/sky130.lib.spice" tt
+
+XM1 dinb din 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6 
+XM2 dinb din vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM7 dd dinb 0 0 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM8 dd dinb vdd vdd sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+
+XM3 vout dinb inp2 inp2 sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+XM4 inp1 dd vout vout sky130_fd_pr__nfet_01v8 L=0.15 W=0.6
+
+XM5 vout dinb inp1 inp1 sky130_fd_pr__pfet_01v8 L=0.15 W=1.2
+XM6 inp2 dd vout vout sky130_fd_pr__pfet_01v8 L=0.15 W=1.2 
+
+
+V1 din 0 PULSE 0 1.8 0ns 100p 100p 5n 10n
+V2 vdd 0 dc 3.3V
+V4 inp2 0 dc 0
+V3 inp1 0 dc 1.65
+
+
+.tran 0.1n 10n
+.control
+run 
+plot din dinb 
+plot inp1 inp2
+plot vout
+.endc
+.end
+
+
+