Diagramme Scicos
fr -
eng
Diagramme de simulation d'un synthétiseur de fréquence à rapport de division entier accroché
//## LO
F_cpf = 20e6;
T_cpf = 1/F_cpf;
sig_ref = 2*%pi
//## VCO
kv = 133e6;
alpha = 6.91e9;
beta2 = 0.15;
j_vco = 30e3;
//## DIVIDER
Fd = 2.50e9;
N = int(Fd/F_cpf)
//## CHARGE PUMP
Icp = 5e-3
Ileak = 8e-6
Ileak_sig = 0e-6
//## LOOP FILTER
fn = F_cpf/290
phi = %pi/4
kvv = kv*2*%pi
[tau1,tau,tau2] = calcul_3eme_ordre(fn,phi,kvv,Icp,N);
//## custom components
C1=820e-12;
C2=150e-12;
R1=1500;
Rvco=5e+3;
Cvco=25e-12;
//tau1=C2*R1;
//tau=C2+C1;
//tau2=R1*C1*C2/(C2+C1);
//tauvco=Rvco*Cvco
s = poly(0,'s');
num = 1+tau1*s;
den = tau*s*(1+tau2*s);
//## LINEAR MODEL
G = kvv*Icp/(2*%pi)*num/(s*den);
H = num/den
GH = kvv*Icp/(2*%pi)*num/(N*s*den)
//## cont_frm
f11=cont_frm(num,den);
s11=syslin('c',f11.A,f11.B,f11.C);
//## tf2ss
f22=tf2ss(num/den,%eps)
s22=syslin('c',f22.A,f22.B,f22.C);
//## SPECTRUM ANALYSIS
Tsampl = 1/100e6
nfft = 2^16
aver = 8
//## SIMULATION EVENTS
Tacqui = 5e-5
Tfin = Tacqui + aver*nfft*Tsampl
Figure : Fonction de transfert en boucle fermé
Figure : Formes temporelles de sortie
Alan Layec INRIA