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new XSPICE example: mixed mode pll circuit
new XSPICE example: mixed mode pll circuit
7 changed files with 449 additions and 0 deletions
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14examples/xspice/pll/README
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16examples/xspice/pll/f-p-det-d-sub.cir
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31examples/xspice/pll/loop-filter.cir
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133examples/xspice/pll/pll-xspice.cir
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40examples/xspice/pll/test-f-p-det.cir
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149examples/xspice/pll/test_vco.cir
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66examples/xspice/pll/vco_sub.cir
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This directory contains a mixed mode pll, combining |
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ngspice and XSPICE circuit blocks. |
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The pll consists of the following blocks: |
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voltage controlled oscillator: vco_sub.cir |
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digital divider and frequency reference: pll-xspice.cir |
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phase frequency detector: f-p-det-d-sub.cir |
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loop filter: loop-filter.cir |
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main simulation control: pll-xspice.cir |
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Two test files are included: |
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test-vco.cir simulates vco frequency versus control voltage |
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test-f-p-det.cir simulates the phase frequency detector and the loop filter. |
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The main building blocks are organised as subcircuits. |
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* frequency-phase detector according to |
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* http://www.uwe-kerwien.de/pll/pll-phasenvergleich.htm |
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.subckt f-p-det d_R d_V d_U d_U_ d_D d_D_ |
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aa1 [d_U d_D] d_rset and1 |
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.model and1 d_and(rise_delay = 1e-10 fall_delay = 0.1e-9 |
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+ input_load = 0.5e-12) |
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|
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ad1 d_d1 d_R d_d0 d_rset d_U d_U_ flop1 |
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ad2 d_d1 d_V d_d0 d_rset d_D d_D_ flop1 |
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.model flop1 d_dff(clk_delay = 1.0e-10 set_delay = 1.0e-10 |
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+ reset_delay = 1.0e-10 ic = 2 rise_delay = 1.0e-10 |
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+ fall_delay = 1e-10) |
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.ends f-p-det |
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* loop filter for pll |
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* in: d_up d_down digital data |
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* out: vout, vco control voltage |
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* according to http://www.uwe-kerwien.de/pll/pll-schleifenfilter.htm |
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.subckt loopf d_U d_D vout |
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.param loadcur=5m |
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.param initcond=2.5 |
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v1 vtop 0 1 |
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v2 vbot 0 -1 |
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abridge-f1 [d_U d_D] [u1 d1] dac1 |
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.model dac1 dac_bridge(out_low = 0 out_high = 1 out_undef = 0.5 |
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+ input_load = 5.0e-12 t_rise = 1e-10 |
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+ t_fall = 1e-10) |
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|
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*top switched current source |
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Gtop vtop vout cur='loadcur*v(u1)' |
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*bottom switched current source |
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Gbot vout vbot cur='loadcur*v(d1)' |
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|
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*passive filter elements |
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.ic v(vout)='initcond' v(c1)='initcond' |
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R2 vout c1 200 |
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C1 c1 0 5n |
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C2 vout 0 5n |
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Rshunt vout 0 10000k |
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.ends |
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* pll circuit using xspice code models |
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.param vcc=3.3 |
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.param divisor=40 |
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.param fref=10e6 |
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.csparam simtime=20u |
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.global d_d0 d_d1 |
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vdd dd 0 dc 'vcc' |
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*vco cont 0 dc 1.9 |
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*PULSE(V1 V2 TD TR TF PW PER) |
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* 10 MHz reference frequency |
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* PULSE(V1 V2 TD TR TF PW PER) |
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vref ref 0 dc 0 pulse(0 'vcc' 10n 1n 1n '1/fref/2' '1/fref') |
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abridgeref [ref] [d_ref] adc_vbuf |
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.model adc_vbuf adc_bridge(in_low = 0.5 in_high = 0.5) |
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|
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*digital zero |
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vzero z 0 dc 0 |
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abridgev3 [z] [d_d0] adc_vbuf |
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.model adc_vbuf adc_bridge(in_low = 'vcc*0.5' in_high = 'vcc*0.5') |
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*digital one |
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ainv1 d_d0 d_d1 invd1 |
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.model invd1 d_inverter(rise_delay = 1e-10 fall_delay = 1e-10) |
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* vco |
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.include vco_sub.cir |
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* buf: analog out |
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* d_digout: digital out |
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* cont: analog control voltage |
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* dd: analog supply voltage |
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xvco buf d_digout cont dd ro_vco |
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* digital divider |
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adiv1 d_digout d_divout divider |
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.model divider d_fdiv(div_factor = 'divisor' high_cycles = 'divisor/2' |
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+ i_count = 4 rise_delay = 1e-10 |
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+ fall_delay = 1e-10) |
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|
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* frequency phase detector |
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.include f-p-det-d-sub.cir |
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Xfpdet d_divout d_ref d_U d_Un d_D d_Dn f-p-det |
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* loop filter |
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.include loop-filter.cir |
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Xlf d_U d_D cont loopf |
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* d to a for plotting |
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abridge-w1 [d_divout d_ref d_U d_D] [s1 s2 u1 d1] dac1 |
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.model dac1 dac_bridge(out_low = 0 out_high = 1 out_undef = 0.5 |
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+ input_load = 5.0e-12 t_rise = 1e-10 |
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+ t_fall = 1e-10) |
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.control |
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set xtrtol=2 |
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tran 0.1n $&simtime uic |
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rusage |
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plot cont s1 s2+1.2 u1+2.4 d1+3.6 |
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plot cont |
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.endc |
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|
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*model = bsim3v3 |
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*Berkeley Spice Compatibility |
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* Lmin= .35 Lmax= 20 Wmin= .6 Wmax= 20 |
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.model N1 NMOS |
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*+version = 3.2.4 |
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+version = 3.3.0 |
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+Level= 8 |
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+Tnom=27.0 |
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+Nch= 2.498E+17 Tox=9E-09 Xj=1.00000E-07 |
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+Lint=9.36e-8 Wint=1.47e-7 |
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+Vth0= .6322 K1= .756 K2= -3.83e-2 K3= -2.612 |
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+Dvt0= 2.812 Dvt1= 0.462 Dvt2=-9.17e-2 |
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+Nlx= 3.52291E-08 W0= 1.163e-6 |
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+K3b= 2.233 |
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+Vsat= 86301.58 Ua= 6.47e-9 Ub= 4.23e-18 Uc=-4.706281E-11 |
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+Rdsw= 650 U0= 388.3203 wr=1 |
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+A0= .3496967 Ags=.1 B0=0.546 B1= 1 |
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+ Dwg = -6.0E-09 Dwb = -3.56E-09 Prwb = -.213 |
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+Keta=-3.605872E-02 A1= 2.778747E-02 A2= .9 |
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+Voff=-6.735529E-02 NFactor= 1.139926 Cit= 1.622527E-04 |
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+Cdsc=-2.147181E-05 |
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+Cdscb= 0 Dvt0w = 0 Dvt1w = 0 Dvt2w = 0 |
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+ Cdscd = 0 Prwg = 0 |
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+Eta0= 1.0281729E-02 Etab=-5.042203E-03 |
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+Dsub= .31871233 |
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+Pclm= 1.114846 Pdiblc1= 2.45357E-03 Pdiblc2= 6.406289E-03 |
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+Drout= .31871233 Pscbe1= 5000000 Pscbe2= 5E-09 Pdiblcb = -.234 |
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+Pvag= 0 delta=0.01 |
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+ Wl = 0 Ww = -1.420242E-09 Wwl = 0 |
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+ Wln = 0 Wwn = .2613948 Ll = 1.300902E-10 |
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+ Lw = 0 Lwl = 0 Lln = .316394 |
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+ Lwn = 0 |
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+kt1=-.3 kt2=-.051 |
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+At= 22400 |
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+Ute=-1.48 |
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+Ua1= 3.31E-10 Ub1= 2.61E-19 Uc1= -3.42e-10 |
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+Kt1l=0 Prt=764.3 |
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|
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.model P1 PMOS |
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*+version = 3.2.4 |
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+version = 3.3.0 |
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+Level= 8 |
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+Tnom=27.0 |
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+Nch= 3.533024E+17 Tox=9E-09 Xj=1.00000E-07 |
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+Lint=6.23e-8 Wint=1.22e-7 |
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+Vth0=-.6732829 K1= .8362093 K2=-8.606622E-02 K3= 1.82 |
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+Dvt0= 1.903801 Dvt1= .5333922 Dvt2=-.1862677 |
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+Nlx= 1.28e-8 W0= 2.1e-6 |
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+K3b= -0.24 Prwg=-0.001 Prwb=-0.323 |
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+Vsat= 103503.2 Ua= 1.39995E-09 Ub= 1.e-19 Uc=-2.73e-11 |
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+ Rdsw= 460 U0= 138.7609 |
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+A0= .4716551 Ags=0.12 |
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+Keta=-1.871516E-03 A1= .3417965 A2= 0.83 |
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+Voff=-.074182 NFactor= 1.54389 Cit=-1.015667E-03 |
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+Cdsc= 8.937517E-04 |
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+Cdscb= 1.45e-4 Cdscd=1.04e-4 |
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+ Dvt0w=0.232 Dvt1w=4.5e6 Dvt2w=-0.0023 |
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+Eta0= 6.024776E-02 Etab=-4.64593E-03 |
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+Dsub= .23222404 |
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+Pclm= .989 Pdiblc1= 2.07418E-02 Pdiblc2= 1.33813E-3 |
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+Drout= .3222404 Pscbe1= 118000 Pscbe2= 1E-09 |
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+Pvag= 0 |
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+kt1= -0.25 kt2= -0.032 prt=64.5 |
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+At= 33000 |
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+Ute= -1.5 |
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+Ua1= 4.312e-9 Ub1= 6.65e-19 Uc1= 0 |
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+Kt1l=0 |
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.end |
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* test frequency-phase detector similar to 12040 |
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.param vcc=3.3 |
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.global d_d0 d_d1 |
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*PULSE(V1 V2 TD TR TF PW PER) |
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v1 1 0 dc 0 pulse(0 'vcc' 10n 1n 1n 10n 20n) |
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v2 2 0 dc 0 pulse(0 'vcc' 8n 1n 1n 10n 20n) |
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*digital zero |
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v3 3 0 dc 0 |
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abridgev1 [1 2 3] [d_sig1 d_sig2 d_d0] adc_vbuf |
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.model adc_vbuf adc_bridge(in_low = 'vcc*0.5' in_high = 'vcc*0.5') |
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*digital one |
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ainv1 d_d0 d_d1 invd1 |
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.model invd1 d_inverter(rise_delay = 1e-10 fall_delay = 1e-10) |
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Xfpdet d_sig1 d_sig2 d_U d_Un d_D d_Dn f-p-det |
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*.include f-p-det-sub.cir |
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.include f-p-det-d-sub.cir |
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* d to a for plotting |
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abridge-w1 [d_sig1 d_sig2 d_U d_D] [s1 s2 u1 d1] dac1 |
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.model dac1 dac_bridge(out_low = 0 out_high = 1 out_undef = 0.5 |
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+ input_load = 5.0e-12 t_rise = 1e-10 |
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+ t_fall = 1e-10) |
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* loop filter |
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.include loop-filter.cir |
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Xlf d_u d_D vco loopf |
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.control |
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set xtrtol=2 |
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tran 0.1n 1000n |
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plot s1 s2+1.2 u1+2.4 d1+3.6 xlimit 100n 200n |
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plot v(vco) |
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.endc |
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.end |
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@ -0,0 +1,149 @@ |
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VCO: 7 stage Ring-Osc. made of gain cells BSIM3 |
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* P.-H. Hsieh, J. Maxey, C.-K. K. Yang, IEEE JSSC, Sept. 2009, pp. 2488 - 2495 |
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* get frequency versus control voltage |
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* measure frequency of R.O. by fft |
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.param vcc=3.3 |
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.csparam simtime=500n |
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.include vco_sub.cir |
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vdd dd 0 dc 'vcc' |
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vco cont 0 dc 2.5 |
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xvco buf digout cont dd ro_vco |
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.option noacct |
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.control |
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set xtrtol=2 |
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set dt = $curplot |
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set curplot = new |
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set curplottitle = "Frequency versus voltage" |
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set freq_volt = $curplot $ store its name to 'freq_volt' |
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setplot $freq_volt |
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let vcovec=vector(5) |
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let foscvec=vector(5) |
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setplot $dt |
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alter vco 0.5 |
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tran 0.1n $&simtime 0 |
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let {$freq_volt}.vcovec[0]=v(cont) |
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linearize buf |
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fft buf |
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* start meas at freq > 0 to skip large dc part |
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meas sp fosc MAX_AT buf from=1e3 to=1e9 |
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let {$freq_volt}.foscvec[0]=fosc |
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plot digout xlimit 140n 160n |
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reset |
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alter vco 1 |
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tran 0.1n $&simtime 0 |
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let {$freq_volt}.vcovec[1]=v(cont) |
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linearize buf |
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fft buf |
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meas sp fosc MAX_AT buf from=1e3 to=1e9 |
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let {$freq_volt}.foscvec[1]=fosc |
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plot digout xlimit 140n 160n |
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reset |
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alter vco 1.5 |
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tran 0.1n $&simtime 0 |
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let {$freq_volt}.vcovec[2]=v(cont) |
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linearize buf |
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fft buf |
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meas sp fosc MAX_AT buf from=1e3 to=1e9 |
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let {$freq_volt}.foscvec[2]=fosc |
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plot digout xlimit 140n 160n |
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reset |
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alter vco 2 |
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tran 0.1n $&simtime 0 |
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let {$freq_volt}.vcovec[3]=v(cont) |
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linearize buf |
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fft buf |
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meas sp fosc MAX_AT buf from=1e3 to=1e9 |
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let {$freq_volt}.foscvec[3]=fosc |
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plot digout xlimit 140n 160n |
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reset |
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alter vco 2.5 |
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tran 0.1n $&simtime 0 |
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let {$freq_volt}.vcovec[4]=v(cont) |
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linearize buf |
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fft buf |
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meas sp fosc MAX_AT buf from=1e3 to=1e9 |
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let {$freq_volt}.foscvec[4]=fosc |
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plot digout xlimit 140n 160n |
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plot tran1.buf tran3.buf tran5.buf tran7.buf tran9.buf xlimit 140n 160n |
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plot mag(sp2.buf) mag(sp4.buf) mag(sp6.buf) mag(sp8.buf) mag(sp10.buf) xlimit 100e6 1100e6 |
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setplot $freq_volt |
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settype frequency foscvec |
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settype voltage vcovec |
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plot foscvec vs vcovec |
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rusage |
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.endc |
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|
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*model = bsim3v3 |
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*Berkeley Spice Compatibility |
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* Lmin= .35 Lmax= 20 Wmin= .6 Wmax= 20 |
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.model N1 NMOS |
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*+version = 3.2.4 |
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+version = 3.3.0 |
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+Level= 8 |
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+Tnom=27.0 |
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+Nch= 2.498E+17 Tox=9E-09 Xj=1.00000E-07 |
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+Lint=9.36e-8 Wint=1.47e-7 |
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+Vth0= .6322 K1= .756 K2= -3.83e-2 K3= -2.612 |
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+Dvt0= 2.812 Dvt1= 0.462 Dvt2=-9.17e-2 |
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+Nlx= 3.52291E-08 W0= 1.163e-6 |
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+K3b= 2.233 |
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+Vsat= 86301.58 Ua= 6.47e-9 Ub= 4.23e-18 Uc=-4.706281E-11 |
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+Rdsw= 650 U0= 388.3203 wr=1 |
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+A0= .3496967 Ags=.1 B0=0.546 B1= 1 |
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+ Dwg = -6.0E-09 Dwb = -3.56E-09 Prwb = -.213 |
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+Keta=-3.605872E-02 A1= 2.778747E-02 A2= .9 |
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+Voff=-6.735529E-02 NFactor= 1.139926 Cit= 1.622527E-04 |
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+Cdsc=-2.147181E-05 |
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+Cdscb= 0 Dvt0w = 0 Dvt1w = 0 Dvt2w = 0 |
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+ Cdscd = 0 Prwg = 0 |
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+Eta0= 1.0281729E-02 Etab=-5.042203E-03 |
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+Dsub= .31871233 |
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+Pclm= 1.114846 Pdiblc1= 2.45357E-03 Pdiblc2= 6.406289E-03 |
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+Drout= .31871233 Pscbe1= 5000000 Pscbe2= 5E-09 Pdiblcb = -.234 |
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+Pvag= 0 delta=0.01 |
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+ Wl = 0 Ww = -1.420242E-09 Wwl = 0 |
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+ Wln = 0 Wwn = .2613948 Ll = 1.300902E-10 |
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+ Lw = 0 Lwl = 0 Lln = .316394 |
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+ Lwn = 0 |
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+kt1=-.3 kt2=-.051 |
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+At= 22400 |
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+Ute=-1.48 |
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+Ua1= 3.31E-10 Ub1= 2.61E-19 Uc1= -3.42e-10 |
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+Kt1l=0 Prt=764.3 |
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|
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.model P1 PMOS |
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*+version = 3.2.4 |
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+version = 3.3.0 |
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+Level= 8 |
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+Tnom=27.0 |
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+Nch= 3.533024E+17 Tox=9E-09 Xj=1.00000E-07 |
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+Lint=6.23e-8 Wint=1.22e-7 |
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+Vth0=-.6732829 K1= .8362093 K2=-8.606622E-02 K3= 1.82 |
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+Dvt0= 1.903801 Dvt1= .5333922 Dvt2=-.1862677 |
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+Nlx= 1.28e-8 W0= 2.1e-6 |
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+K3b= -0.24 Prwg=-0.001 Prwb=-0.323 |
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+Vsat= 103503.2 Ua= 1.39995E-09 Ub= 1.e-19 Uc=-2.73e-11 |
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+ Rdsw= 460 U0= 138.7609 |
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+A0= .4716551 Ags=0.12 |
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+Keta=-1.871516E-03 A1= .3417965 A2= 0.83 |
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+Voff=-.074182 NFactor= 1.54389 Cit=-1.015667E-03 |
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+Cdsc= 8.937517E-04 |
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+Cdscb= 1.45e-4 Cdscd=1.04e-4 |
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+ Dvt0w=0.232 Dvt1w=4.5e6 Dvt2w=-0.0023 |
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+Eta0= 6.024776E-02 Etab=-4.64593E-03 |
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+Dsub= .23222404 |
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+Pclm= .989 Pdiblc1= 2.07418E-02 Pdiblc2= 1.33813E-3 |
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+Drout= .3222404 Pscbe1= 118000 Pscbe2= 1E-09 |
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+Pvag= 0 |
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+kt1= -0.25 kt2= -0.032 prt=64.5 |
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+At= 33000 |
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+Ute= -1.5 |
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+Ua1= 4.312e-9 Ub1= 6.65e-19 Uc1= 0 |
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+Kt1l=0 |
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.end |
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@ -0,0 +1,66 @@ |
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* VCO: 7 stage Ring-Osc. made of gain cells BSIM3 |
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* P.-H. Hsieh, J. Maxey, C.-K. K. Yang, IEEE JSSC, Sept. 2009, pp. 2488 - 2495 |
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* automatically tune Vdd to achive a desired frequency of oscillation |
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* measure frequency of R.O. either by delay measurement or by fft |
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|
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***** ring oscillator as voltage controlled oscillator *************** |
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* name: ro_vco |
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* aout analog out |
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* dout digital out |
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* cont control voltage |
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* dd supply voltage |
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|
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.subckt ro_vco aout dout cont dd |
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* ignition circuit (not needed) |
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* feedback between in and out, pulse to help start oscillation |
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vin inm1 outp7 dc 0 |
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*vin inm1 outp7 dc 2.5 pulse 2.5 0 0.1n 5n 1 1 1 |
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*vin2 inp1 outp7 dc -0.5 pulse -0.5 0 0.1n 5n 1 1 1 |
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vin2 inp1 outm7 dc 0 |
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vss ss 0 dc 0 |
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ve sub 0 dc 0 |
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vpe well 0 dc 3.3 |
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* gain cell |
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.subckt gaincell dd ss sub well co in- in+ out- out+ |
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mn1 out- in+ ss sub n1 w=2u l=0.35u AS=3p AD=3p PS=4u PD=4u |
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mn2 out- out+ ss sub n1 w=2u l=0.35u AS=3p AD=3p PS=4u PD=4u |
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mn3 out+ out- ss sub n1 w=2u l=0.35u AS=3p AD=3p PS=4u PD=4u |
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mn4 out+ in- ss sub n1 w=2u l=0.35u AS=3p AD=3p PS=4u PD=4u |
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mp1 out- co dd well p1 w=4u l=0.35u AS=7p AD=7p PS=6u PD=6u |
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mp2 out+ co dd well p1 w=4u l=0.35u AS=7p AD=7p PS=6u PD=6u |
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.ends gaincell |
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|
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* inverter |
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.subckt inv2 dd ss sub well in out |
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mn1 out in ss sub n1 w=6u l=0.35u AS=12p AD=12p PS=16u PD=16u |
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mp1 out in dd well p1 w=12u l=0.35u AS=24p AD=24p PS=28u PD=28u |
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.ends inv2 |
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|
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* inverter |
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.subckt inv1 dd ss sub well in out |
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mn1 out in ss sub n1 w=2u l=0.35u AS=3p AD=3p PS=4u PD=4u |
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mp1 out in dd well p1 w=4u l=0.35u AS=7p AD=7p PS=6u PD=6u |
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.ends inv1 |
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|
|||
* chain of 25 inverters + output buffer |
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xinv1 dd ss sub well cont inm1 inp1 outm1 outp1 gaincell |
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xinv2 dd ss sub well cont outp1 outm1 outm2 outp2 gaincell |
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xinv3 dd ss sub well cont outp2 outm2 outm3 outp3 gaincell |
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xinv4 dd ss sub well cont outp3 outm3 outm4 outp4 gaincell |
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xinv5 dd ss sub well cont outp4 outm4 outm5 outp5 gaincell |
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xinv6 dd ss sub well cont outp5 outm5 outm6 outp6 gaincell |
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xinv7 dd ss sub well cont outp6 outm6 outm7 outp7 gaincell |
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* analog out (two stage buffer) |
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xinv11 dd 0 sub well outm1 outm2 inv1 |
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xinv12 dd 0 sub well outm2 aout inv2 |
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cout aout 0 0.2pF |
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*digital out |
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abridge1 [aout] [dout] adc_buff |
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.model adc_buff adc_bridge(in_low = 'vcc*0.5' in_high = 'vcc*0.5') |
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.ends ro_vco |
|||
****************************************************************** |
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