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009_mos_prop_delay : Propagation delay

009_mos_prop_delay : Propagation delay

009_mos_prop_delay : Propagation delay

Requires: SmartSpice & Smartview

Minimum Versions: SMARTSPICE 4.6.5.R

The input deck uses a 32 input NAND gate with .TRAN analysis to demonstrate the rubberbanding of a complete block rather than a individual device.

Graphics

initial_waveforms.png

Input Files

rubberband_example_09.in

*32-INPUT NAND GATE ( 132 MOSFETS )
* SSPICE INVESTIGATES THE DEPENDENCE OF THE PROPAGATION DELAY
* OF THE CICUIT OUTPUT SIGNALS ON TWO MOSFET MODEL PARAMETERS
*
.SUBCKT  NAND 1 2 3 
M1  3 1 VDD VDD   MODP   W=10UM   L=3U     AS=100P   AD=100P
M2  3 2 VDD VDD   MODP   W=10UM   L=3U     AS=100P   AD=100P
M3  3 1  6  0     MODN   W=10UM   L=3U     AS=100P   AD=100P
M4  6 2  0  0     MODN   W=10UM   L=3U     AS=100P   AD=100P
.ENDS NAND
.SUBCKT NOR  1 2 3 
M1  6 1 VDD1 VDD1   MODP   W=10UM   L=3U     AS=100P   AD=100P
M2  3 2  6   VDD1   MODP   W=10UM   L=3U     AS=100P   AD=100P
M3  3 1  0    0     MODN   W=10UM   L=3U     AS=100P   AD=100P
M4  3 2  0    0     MODN   W=10UM   L=3U     AS=100P   AD=100P
.ENDS NOR
.SUBCKT INV 1 2 
M1  2 1 VDD2 VDD2   MODP   W=10UM   L=3U     AS=100P   AD=100P
M2  2 1  0    0    MODN    W=10UM   L=3U     AS=100P   AD=100P
.ENDS INV
.SUBCKT INP8 11 12 10
X1  11 12 3  NAND
X2  12 12 4  NAND
X3  12 12 5  NAND
X4  12 12 6  NAND
X5  3 4 7   NOR
X6  5 6 8   NOR
X7  7 8 9   NAND
X8  9 10  INV 
.ENDS INP8
.GLOBAL VDD VDD1 VDD2 
*......... CIRCUIT .........................................
VDD  VDD 0  DC 5.0V
VDD1  VDD1 0  DC 5.0V
VDD2  VDD2 0  DC 5.0V
V1  11 0  PULSE (0 5 2NS 1NS 1NS 20NS 40NS)
V2  12 0  PULSE (0 5 2NS 1NS 1NS 60NS 120NS)
V3  13 0  DC 5.V
X1  11 12 1  INP8
X2  13 12 2  INP8
X3  13 12 3  INP8
X4  13 12 4  INP8
X5  1  2  5  NAND
X6  3  4  6  NAND
X7  5  6  7  NOR
CL  7 0  20.FF
.MODEL  MODP PMOS  (LEVEL=49    UO=275 CBD=40.0FF
+                   PB=0.8  PHI=0.6 GAMMA=0)
.MODEL  MODN NMOS  (LEVEL=49 RS=10 rd=10   UO=550 CBD=40.0FF
+                   PB=0.8   PHI=0.6 GAMMA=0)
*......... TRAN, MEASURE and MODIF COMMANDS .................

.TRAN  1NS 80NS   from_step=2n  67n 10n   to=78ns

.save v(7)  v(5)

.options nomod numdgt=15

.END

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