The drive strength is configured with PSKEY_XTAL_LVL. The default level for this PS Key is sufficient for typical
crystals. The level control is set in the range 0 to 15, where 15 is the maximum drive level.
Increasing the crystal amplifier drive level increases the transconductance of the crystal amplifier, which creates an
increase in the oscillator margin (ratio of oscillator amplifiers is equivalent to the negative resistance of the crystal
ESR).
Note:
Excessive amplifier transconductance can lead to an increase in the oscillator phase noise if the oscillator
amplifier is excessively overdriven. Set the transconductance to the minimum level to give the desired oscillation
3Tabn3WPTCemeh..hr11agiengape..ratr21nlcrf■■■■■ariteraefrsimoivayte:cmiestoeroet.tgCCCCrnaareseHmdsloiioCNttrnnshauaiutg=a=it=arrsenc=ht=yntitcdSTgInaeaOsPniIrttrgnrinanhaattctnresvccatateuntt-eiaeroeiclctisplnvortl.houcnoaacSateiofehasalprdptnesaclcphRpcdictadecaelTalaaueppaaccfcparpcranitosatoreiabtaacfyraisiv.clicnsinseinctjiitiacdactttticMaoaca3arneemee2lr-n.ctsicn2cnaoicecoeao:incsfaeRrsfpToceentnetanhouhTnrgpeacebnieasMtogXinettaceX=EwcaisTvrmoqor−nTcqeyAeyuocdusAor2-sLirentavdctLπee_aaadaote_bIslfipllN,uoln2lOieeloaswce(ns,tnCUstctwduashac3choTmeneienai.Tcu1el1,ecelcsphaytr-.c:seCnee5tpTtaoeiNi.ososiiaanemFnrfiengsbr+nspoage.Tmtmlod(auerAmaqCamCntO.otulb30pciscaeviseln.+noolee1neictnCf-Ci,m.idimcc3eliRoElnihyan..roeue1scqittputds)iusnuo(teiCfrPpansf-peitut,oaciaefMotuetirnnehantoro+cdnersfe3nCeatiMXtvd.ddnii1canT--ratati)lsoACvxur)yeh2eeL,aasospSsoiawstafermttsehcitpvhpinehtetealgoeisfnetwminhhecleeuretbc.gomnaeatcnertoainpv1rltcer6.ceuC,arvleas2oeset0nneiss1tUcmtptit3ahdahnFSpeeneitarcetcehtqhietuseaichnvdroacyruelisevltdenartl
Table 3.3 shows the specification for an external crystal.
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