kkantham
Newbie level 4
ring oscillator
hi guys i have a problem in transcient analysis of 3 stage simple ring oscillator in 45nm cmos technology. i got dc analysis but with 3rd inverter in saturation.
i could not get transcient curves and could not measure delay parameters. this is my netlist can any body help me in correcting this
netlist
------------------------------------------------------------------
.option ingold
.param vdd=1.1
.ic v(1)=vdd
***********************************************************************
* Subcircuits
***********************************************************************
.subckt inv a y vdd 0 n=90n p=180n
M1 y a 0 0 nmos l=45n w='n' ad='0.5u*n' as='0.5u*n' pd='1u+2*n' ps='1u+2*n'
M2 y a vdd vdd pmos l=45n w='p' ad='0.5u*p' as='0.5u*p' pd='1u+2*p' ps='1u+2*p'
.ends inv
***********************************************************************
* Simulation netlist
***********************************************************************
vdd vdd 0 dc 'vdd'
vin 1 0 dc
x1 1 2 vdd 0 inv
x2 2 3 vdd 0 inv
x3 3 1 vdd 0 inv
.dc vin 0 'vdd' 0.05
.plot dc v(1) v(2) v(3)
.print dc v(1) v(2) v(3)
.tran .1ns 10ns
.plot tran v(1) v(2) v(3)
.measure tran tpdr TRIG v(2) val='vdd/2' fall=1 TARG v(3) val='vdd/2' rise=1
.measure tran tpdf TRIG v(2) val='vdd/2' rise=1 TARG v(3) val='vdd/2' fall=1
.measure tpd param='(tpdr+tpdf)/2'
.OP
.probe
**library input files**
.include `45nm.inc`
.end
can any body please help me in correcting this netlist to prevent saturation and to oscilllate to get curves in .tran analysis
hi guys i have a problem in transcient analysis of 3 stage simple ring oscillator in 45nm cmos technology. i got dc analysis but with 3rd inverter in saturation.
i could not get transcient curves and could not measure delay parameters. this is my netlist can any body help me in correcting this
netlist
------------------------------------------------------------------
.option ingold
.param vdd=1.1
.ic v(1)=vdd
***********************************************************************
* Subcircuits
***********************************************************************
.subckt inv a y vdd 0 n=90n p=180n
M1 y a 0 0 nmos l=45n w='n' ad='0.5u*n' as='0.5u*n' pd='1u+2*n' ps='1u+2*n'
M2 y a vdd vdd pmos l=45n w='p' ad='0.5u*p' as='0.5u*p' pd='1u+2*p' ps='1u+2*p'
.ends inv
***********************************************************************
* Simulation netlist
***********************************************************************
vdd vdd 0 dc 'vdd'
vin 1 0 dc
x1 1 2 vdd 0 inv
x2 2 3 vdd 0 inv
x3 3 1 vdd 0 inv
.dc vin 0 'vdd' 0.05
.plot dc v(1) v(2) v(3)
.print dc v(1) v(2) v(3)
.tran .1ns 10ns
.plot tran v(1) v(2) v(3)
.measure tran tpdr TRIG v(2) val='vdd/2' fall=1 TARG v(3) val='vdd/2' rise=1
.measure tran tpdf TRIG v(2) val='vdd/2' rise=1 TARG v(3) val='vdd/2' fall=1
.measure tpd param='(tpdr+tpdf)/2'
.OP
.probe
**library input files**
.include `45nm.inc`
.end
can any body please help me in correcting this netlist to prevent saturation and to oscilllate to get curves in .tran analysis