IR1176
3 -PLL Naturalfrequency:
ωn =2πfn(KHz)= √ Ichpump(uA) x Kvco_ac(KHz/V) / C(nF)
Choose Cfsuchthat Cf=C/16
4 -PLL Damping factorcalculations:
P = πE-3 x Rf (KOhms) x C(nF) x fn(KHz)
Typical value for P is 0.707. (Critically damped)
5 -Advancetim ing:
Tadv(nsec) = RADV (KOhms)*10 -+160
W hereRADV isresistancefrom RADV1 orRADV2 toground.
Example C:RADV=10Kohms willresultin Tadv=10*10-+160==19006nsnescec..
6-Dead time calculations:
TTdd((nnsseecc)=)0=.069.6*R9d*Ct(KdOt(hpmFs)*)*(CRddtt(p(KF)Ω+)+50.1(F5o)r(FVdodr=V5dVd)=5V)
W hereRdtisresistancebetweenpinsDTIN1andDTOUT1orDTIN2and
DTOUT2.Cdtiscapacitancefrom DTIN1 or DTIN2 toground.
Example D: Rd=2KW and Cdt=100pF will result in Td=148.35nsec.
Fig. 4 PLL loop filter component definitions
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