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Type Ia SNe along redshift:the R (Si ii )ratio and the expansion velocities in intermediate z supernovae G.Altavilla 1,P.Ruiz–Lapuente 1,2,A.Balastegui 1,J.M′e ndez 1,3,M.Irwin 4,C.Espa?n a–Bonet 1,K.Schahmaneche 5,C.Balland 5,R.S.Ellis 4,6,S.Fabbro 7,G.Folatelli 8,A.Goobar 8,W.Hillebrandt 2,R.M.McMahon 4,M.Mouchet 5,A.Mourao 7,S.Nobili 8,R.Pain 5,V.Stanishev 8,N.A.Walton 4Received Running title:Type Ia SNe along redshift
ABSTRACT
We study intermediate–z SNe Ia using the empirical physical diagrams which enable to learn about those SNe explosions.This information can be very useful to reduce systematic uncertainties of the Hubble diagram of SNe Ia up to high z.The study of the expansion velocities and the measurement of the ratio
R(Si ii)allow to subtype SNe Ia as done in nearby samples.The evolution of this ratio as seen in the diagram R(Si ii)–(t)together with R(Si ii)max versus (B-V)0indicate consistency of the properties at intermediate z compared with the nearby SNeIa.At intermediate–z,expansion velocities of Ca II and Si II are found similar to those of the nearby sample.This is found in a sample of 6SNe Ia in the range0.033≤z≤0.329discovered within the International Time Programme(ITP)of SNe Ia for Cosmology and Physics in the spring run of20029.Those supernovae were identi?ed using the4.2m William Herschel Telescope.Two SNe Ia at intermediate z were of the cool FAINT type,one being a SN1986G–like object highly reddened.The R(Si ii)ratio as well as subclassi?cation of the SNe Ia beyond templates help to place SNe Ia in their sequence of brightness and to distinguish between reddened and intrinsically red supernovae.This test can be done with very high z SNe Ia and it will help to reduce systematic uncertainties due to extinction by dust.It should allow to map the high–z sample into the nearby one.
Subject headings:supernovae:general–supernovae:individual:2002li,2002lj,
2002lk,2002ln,2002lo,2002lp,2002lq,2002lr,–cosmology:observations
1.Introduction
The measurements using Type Ia Supernovae of the expansion rate of the Universe led to the discovery of its acceleration(Riess et al.1998;Perlmutter et al.1999)and has opened a new?eld in the identi?cation of the driving force of the accelerated expansion,the so called dark energy.A large local supernova sample was?rst studied in the Calan–Tololo survey(Hamuy et al.1996)and nowadays in a series of campaigns at low redshift by various collaborations.At high-z,the?rst supernova samples were gathered by the Supernova Cosmology Project(Perlmutter et al.1999;Knop et al.2003;Hook et al.2005)and the High–Z SN team/ESSENCE(Riess et al.1998;Tonry et al.2003;Barris et al.2004; Krisciunas et al.2005;Clocchiatti et al.2005).In the last years,the high–z redshift range has been targeted as well by the Supernova Legacy Survey(Astier et al.2005).The combination of the discoveries made by all these collaborations will provide hundreds of SNe Ia at z>0.2.At very high–redshift,the Higher–Z Team using the Hubble Space Telescope concentrates in the discovery of supernovae at z>1to better constraint dark energy(Riess et al.2005).This is also the target of the latest runs of the Supernova Cosmology Project which is presently studying SNe Ia in galaxy clusters at very high z.
While the low and high redshift intervals are often targeted,the intermediate redshift
(0.1～ a well covered sample of SNe Ia between z～0.1and z～0.4.In this paper,we present the spectroscopic results of the observations done in spring2002,of the ITP project on supernovae for their physics and cosmology(P.I.Ruiz–Lapuente)10.We discuss where these supernovae stand in the empirical physical diagrams used to describe the supernova density pro?le and temperature.The results of the photometric follow–up and their cosmological implications will be presented in a forthcoming paper.There are prospects that SDSS–II(Sako et al.2005a,b)will provide a large sample of SNe Ia at those z while the SNFactory(Aldering et al.2004)will concentrate in supernovae at z～0.1.At ENO, our own collaboration plans to move to very high–z to carry campaigns that will explore the physics of SNe Ia in detail at those high–z in a similar way as done for the nearby sample.Physical properties of SNe Ia can be better studied within intensive supernova campaigns by collecting a large database of spectra and photometry for each individual supernova.This task has been the aim of the RTN on Physics of Type Ia supernovae which compares each single SNIa with model spectra to better understand SNe Ia explosions (Hillebrandt et al.2005).Detailed spectral evolution provides a complete probe of the SNe Ia ejecta:chemical composition,velocity and other physical characteristics of the layers that successively become transparent. At high–z,the observing time per supernova has to be optimised.Long exposure times are needed to obtain good S/N spectra for the large amount of candidates in the supernova searches.This prevents from having a complete sequence of spectra.However,as we will show here,one can go a step beyond what has been done up to now with high–z SN spectra and do a?ner classi?cation.In this intermediate–z campaigns(see Ruiz–Lapuente2006for a review),we have seen how information similar to the one gathered in nearby SNe Ia can be gathered at all z. Spectral studies of intermediate z supernovae have started to incorporate the study of expansion velocities of the material within the ejecta(Altavilla et al.2005;Balastegui et al.2005;Mendez et al.2005;Balland et al.2006).The intermediate redshift spectra gathered o?er here the possibility of investigating where the SNe Ia stand in distribution of chemical elements in the velocity space and the temperature within the ejecta(Branch et al.1993a;Hatano et al.2000;Benetti et al.2004;Benetti et al.2005;Branch et al.2006). This opens a new window inside the supernova ejecta and allows to test the existence of continuity in the temperature and spatial gradient characteristics of SNe Ia.Ultimately, these intermediate redshift Type Ia SNe will help to?ll the gap between the local and high–z SN samples,reducing the statistical uncertainties by means of an evenly sampled Hubble diagram.These supernovae are to be used in cosmology in conjunction with those gathered by other surveys. The outline of the paper is as follows.In section2we present the observations and the data reduction procedure,and in section3the SN candidates classi?cation.In section4we comment the results on individual objects and bring them into comparison with the nearby sample.Matches of the spectra to nearby SNe Ia are examined.In section5the physical diagrams for intermediate z SNe Ia are?rst buildt up in a way similar to what is done in nearby SNeIa.The prospects to use these diagrams to reduce systematic uncertainties are shown.Further discussion is presented in section6.A brief summary of the run and conclusions are reported in section7. 2.Observations and data reductions Spectra of the SN candidates were obtained using the4.2-m William Herschel Telescope (WHT)11.Observations were done using the spectrograph ISIS on June10th and11th, 2002(Table1).A dichroic allowed to carry simultaneous observations in the blue and red channels,which are optimised for their respective wavelength ranges(～3000–6000?A,～5000–10000?A).In the blue,the R158B grating was used in conjunction with the EEV12 detector.In the red,we used the R158R grating+GG495?lter12and the MARCONI2 detector.In the red channel fringing begins at about8000?A and increases to～10per cent at9000?A.A longslit of1.2arcseconds was used in the?rst night,under good weather conditions,and a longslit of1.03arcseconds was adopted in the second night,under excellent weather conditions(except for SN2002lk and one spectrum of SN2002lj,which were observed at the beginning of the night with a1.2”slit).A journal of the spectral observations is given in Table1. Spectra were reduced following standard IRAF13procedures.All images were bias subtracted and then?at?elded using dome?ats.The one dimensional spectrum extractions were weighted by variance based on the data values and a Poisson/CCD model using the gain and read noise parameters.The background was interpolated by?tting two regions beside the spectra and then subtracted.Reference spectra of Cu-Ne-Ar lamps were used for the wavelength calibration.The results were checked measuring the position of bright [O i]sky lines at5577?A and6300?A and,when necessary,a rigid shift was applied to the spectrum to be consistent with these values.The spectra were?ux calibrated using spectrophotometric standard stars observed at the start and at the end of each night. Correction for atmospheric absorption was applied to the red arm spectra.The blue and the red sections were joined in a single spectrum and multiple spectra of the same object were then combined in order to improve the signal to noise ratio.Spectra with di?erent exposure times were weighted accordingly. 3.Classi?cation 3.1.Object,redshift and phase determination Spectra can be inspected visually in order to give a rough classi?cation of the SN candidate,where the main feature used to discriminate between Type Ia,Type II SNe or‘other’sources(typically QSOs or AGN)is the presence/absence of the strong Si ii absorption at～6150?A(rest-frame)and the typical S ii～5400?A(rest–frame)‘W’feature for Type Ia SNe.Type II SNe show the characteristic Balmer series P–Cygni pro?les,most noticeably the Hαspectral feature.For a correct classi?cation,one has to be aware of the possible confusion between SNe Ia and SNe Ic.This possibility increases its chances for cool SNIa events when only one spectrum is available.As it will be shown in this paper, such possibility can be reduced if one uses the physical diagrams(expansion velocity and R(Si ii))in intermediate and high–z SNe Ia.For all those reasons and to?nd the best match in a library of SNe Ia,it is required to follow an automatic procedure that will enable to size the di?erence of the spectra of the SNe Ia with those of an archive from a large sample of nearby SNe Ia at all phases. The redshift of the supernova is obtained from the redshift of the galaxy lines.In case of no emission lines,it can be obtained by the algorithm.In our sample,the spectra were inspected looking for typical narrow galaxy lines:Balmer lines,[O ii]λ3727,[O iii]λ5007, [N ii]λ6583,[S ii]λ6716,6731).Images of the host galaxy of the supernovae are shown in Figures1,3,5,7,9,and11and?gures of the supernova spectra with the emission lines of the underlying host galaxy are shown in Figures2,4,6,8,10,and12(top panels).The lines used for the redshift determination(when present)are shown.Uncertainties on the redshifts are of the order of0.001and they have been estimated measuring the dispersion of the redshift determinations obtained from each identi?ed galaxy line. The following step was taken to re?ne the Type Ia SN classi?cation by means of two di?erent classi?cation algorithms developed to this aim.The?rst classi?cation program transforms the spectra into rest–frame and compares it to a set of Type Ia supernovae spectral templates originally prepared by Nugent,Kim,&Perlmutter(2002),and later adapted by Nobili et al.(2003).These spectral templates range from19days before maximum to70days after maximum,and the wavelength coverage is from2500?A to25000?A.Both the spectra and the templates are normalized in the wavelength range selected for the comparison,and then the spectra are again rescaled and shifted in the?ux axis until the best match is found,see Figs.2,4,6,8,10,and12(middle panels)This procedure uses the whole spectrum and the result is not based on a few key features only. In an interactive mode,the algorithm asks for a smoothing length and aσlevel to clean spikes in the observed spectrum.In this second mode,the procedure allows the user to specify the wavelength interval or to reject wavelength intervals of the comparison spectrum.This can be useful to reject a region of the spectrum highly contaminated with atmospheric absorption lines.Finally,the user can select the interval of redshifts and epochs used in the comparison. Mathematically the algorithm works by?nding the minimumχ2of the observed spectrum compared with spectra of all the possible values of the epoch,j,and the redshift, z: χ2 j (z)= n i=1 [f(λi)?F j(λi,z)]2 SN normalized?ux at wavelengthλi,and F j(λi,z)is the template normalized?ux at wavelengthλi,epoch j,and redshift z.The algorithm delivers rest–frame epoch,?ux scale and redshift as parameters.If the redshift is known from the narrow galaxy lines,the algorithm takes it as given and the redshift is not used in the minimization. Once the?rst classi?cation is obtained based on templates,a second analysis is done using an algorithm that compares the SNe Ia with those of the Padova SN Catalogue and other spectra available in the literature(we also made use of the SUSPECT database14).This allows to?nd a real template which best?ts the SN Ia(Figs.2,4,6,8,and10,lower panel).The two algorithms Genspecphase and Genspecsubtype were developed for this programme and can be used in campaigns at all redshifts.Results with the redshift z and phase determination can be seen in Table2. We estimated the spectral epoch and its uncertainty by comparing the phases obtained matching the spectra with the synthetic and real templates.We assumed a minimum error of±2days(see also Riess et al.1997).The comparison of the spectral phaseτspec with the phasesτpho determined from the photometric data(see Table2)shows that the spectral epochs are correct within a few days,with a scatter ofσ=3.5days(Fig.13).This value is consistent with the adopted spectroscopic phase error bars. SN2002lk presented an interesting test for classi?cation.It was an intrinsically red(cool) SNIa and in addition to it,it is highly reddened.A rough approach might have mistaken it for a SNIc at another phase.We included a number of intrinsically red(cool)SNeIa in our database as well as Type Ic supernovae to increase the quality of the classi?cation. Consistency is found with the color light curves and the spectral classi?cation. Observed and template spectra have been smoothed and tilted with an absorption amount derived empirically within the classifying procedure.This‘reddening factor’may not be totally due to absorption,and it is applied to correct for light losses due to observations with the slit out of the parallactic angle and/or to take into account di?erent colours between targets and templates,and/or to take into account reddened templates.In some cases the spectral templates have been slightly red-or blueshifted to account for the small di?erences in the expansion velocities between the template and the observed SN. The peculiar Type Ia SN2002lk and Type II supernovae have been compared with real templates only(Figs.12,14,15). Table3summarizes the results of the classi?cation of the host galaxies of all SN candidates. 3.2.Host galaxy morphology Host galaxy morphology identi?cation is usually done exploiting good imaging and spectra(Sullivan et al.2003).In our sample,a certain visual identi?cation of the host galaxy morphology is feasible for two objects only:SN2002lq(Fig.7),and SN2002lk(Fig. 11).The latter is a Type Ia SN similar to the underluminous SN1986G,which exploded in a spiral galaxy(for a discussion on the host galaxies of subluminous SNe,see Howell2001). This galaxy has been classi?ed as spiral since its ellipticity,larger than7,is not consistent with an elliptical galaxy and,although it is observed almost edge on,the existence of some structure,as a dust lane,can be detected.An image of the galaxy about one year after explosion reveals also the bulge of the galaxy,hidden in Fig.11by the SN light. The rest of the galaxy images do not give hints on the galaxy morphology,being compatible with both elliptical and spiral galaxies(in the latter case the possible spiral structure is unresolved)(Figs.1,3,5,and9).Since we have no spectra of the host galaxies alone,the identi?cations given are made exclusively on the basis of the galaxy lines contaminating the SNe spectra(Kennicutt1992).Thus,we will only distinguish between spheroidal galaxies(ellipticals and lenticulars)and spiral galaxies(without giving any further subclassi?cation). SN2002li and SN2002lq host galaxies are classi?ed as spiral galaxies,since they have a good number of lines from the Balmer series.The host galaxy morphology of the SN2002lq host can be also inferred from visual inspection,while SN2002li host galaxy structure is not as clear as the previous case. SN2002lj lacks galaxy lines.Without any clear Balmer emission line,we have classi?ed it as a spheroidal galaxy. SN2002lp has Hα,Hγand Hθin emission,but very faint.Its host galaxy is possibly spiral. The spectrum of SN2002lr presents also narrow emission lines. The Type II SNe,SN2002ln and SN2002lo,show narrow emission lines of the Balmer series.Their host galaxies have been classi?ed as spirals(Table3). 4.Spectroscopic classi?cation 4.1.Type Ia Supernovae SN2002li This is the farthest supernova discovered in this search(z=0.329).Fig.2(bottom panel) shows the comparison with SN2000E(Valentini et al.2003),a SN spectroscopically almost identical to SN1990N,i.e.a typical Type Ia SN.Both the comparison with SN2000E and Nobili’s spectral templates(Fig.2,middle panel)suggest that the SN2002li phase corresponds to a few days before maximum. The blue-shifted H and K lines at3950?A indicate that the expansion velocity of Ca ii in SN2002li is～17200km s?1,lower than for SN2000E(～21000km s?1).The signal to noise ratio does not allow a reliable determination of the expansion velocity of Si ii at～6150?A. Photometric data suggest that SN2002li is a slow decliner object(?m15(B)～0.79±0.22), but being spectroscopically normal.In the local sample,slow decliners are often normal spectroscopically(Hamuy et al.2002). SN2002lj The redshift of SN2002lj has been derived from SNe features due to the absence of measurable galaxy emission lines.Both the match with a real SN(SN1994D,Patat et al. 1996)(Fig.4,bottom panel)and a template spectrum(Fig.4,middle panel)suggest that the observed epoch for SN2002lj is about a week past maximum.Since SNeIa still show S ii features between5500?A and5700?A7days after maximum,the absence of these features in the SN2002lj spectrum suggests a phase between7and10days past maximum.The redshift was found by comparison with the template SN features,thus most of them have the same expansion velocity,except Si ii at6355?A,whose expansion velocity for SN2002lj is lower(～8900km s?1)than the one measured for SN1994D(～9800km s?1). SN2002lp The?nding chart for this SN(Fig.5)shows the large o?set from the host galaxy.The comparison of the spectra of SN2002lp with that of1989B at maximum(Barbon et al. 1990;Wells et al.1994)shows that they are quite similar(Fig.6,bottom panel).The match with a template at day3after maximum(Fig.6,middle panel),con?rms that the spectrum of SN2002lp was taken close to maximum.The expansion velocity measured from the Si ii unresolved doublet6355?A(～10400km s?1)is almost coincident with the one measured for SN1989B(～10000km s?1).The absorption dip at～5800?A,identi?ed as Si ii5972?A,is stronger than in SN1989B.This is quanti?ed by the R(Si ii)parameter, or ratio of the two Si II absorptions dips,i.e.the one at～5800?A and the one at～6150?A (Nugent et al.1995).In SN2002lp,R(Si ii)is0.50±0.05and in SN1989B is0.29±0.05 for the same period. The match with a template at day3after maximum,con?rms that the spectrum of SN2002lp was taken near maximum.The expansion velocities measured from the Si ii unresolved doublet(6355?A)and Ca ii lines(3950?A)(～10400km s?1,～13800km s?1 respectively)are almost coincident with the ones measured for SN1981B(～10400km s?1,～14000km s?1).While the velocities for SN2002lp are in the range of those found in SN1981B,the absorption dip at～5800?A,identi?ed as Si ii5972?A,is stronger than in SN 1981B.In SN1981B,R(Si ii)is0.16±0.05near maximum,a value which is typical for normal SNe Ia.The spectral comparison with the complete SNe Ia library?nds that SN 1989B is the best match for this supernova(Fig.6,bottom panel). SN2002lq The Si ii(6355?A)feature if existent,is very faint but the comparison with SN1990N, a typical SN Ia with good spectral coverage(Leibundgut et al.1991),suggests that SN 2002lq is a Type Ia SN observed about one week before maximum(Fig.8,bottom panel). Matching synthetic templates gives a phase of7days before maximum for this supernova (Fig.8,middle panel).The only well visible feature in this low S/N spectrum is Ca ii line at3950?A,and its expansion velocity(～18900km s?1),measured with large uncertainty, seems somewhat lower than that of SN1990N(～21000km s?1). SN2002lr This Type Ia supernova was observed about10days after maximum,as derived from?tting the templates and?tting to real SNe Ia(Fig.10,middle and bottom panels).SN2002lr spectrum is similar to one of SN1994D(Patat et al.1996)10days past maximum.The expansion velocity derived from Si ii(6355?A)(～8600km s?1)is similar to the one derived for SN1994D(～9500km s?1).The expansion velocity measured from the Ca ii line at3950?A is～12800km s?1but it is not possible to compare this value with the corresponding one in SN1994D because the limited spectral range of the template does not allow the measurement of the Ca ii line. SN2002lk For SN2002lk two di?erent spectra are available since it was observed in two consecutive nights(Fig.12).The strong similarities between the spectra of SN2002lk and SN1986G (Phillips et al.1987);Padova SN Catalogue),suggest that SN2002lk is a SN1986G–like event observed a few days before maximum.Due to the spectrum peculiarities,a comparison with Nobili’s spectral templates is not appropriate.In Fig.12,the spectra of SN1986G have been shifted in wavelength in order to match better that of SN2002lk.This small shift takes into account the di?erent expansion velocities of the two objects.For SN2002lk the velocity determined from the Si ii line at6355?A is～14500km s?1,while for SN1986G is～10800km s?1.The signi?cant di?erence between the two values may be attributed to di?erent explosion energy.SN2002lk is characterized by higher expansion velocity,slower decline rate in the B light curve(?m15(B)～1.23±0.02),and similar R(Si ii)with respect to SN1986G.Thus,SN2002lk,in its turn,can be considered a less extreme object with respect to SN1986G,suggesting a continuous transition from object to object.We notice that similar high expansion velocity was found for SN1998de,a1991bg-like SN(Modjaz et al.2001),whose expansion velocity(6days before maximum)derived from the Si ii(6355 ?A)minimum was13300km s?1(Garnavich,Jha,&Kirshner1998). As far as reddening is concerned,the detection of the Na i D(λλ5890,5896?A)allows us to estimate the host galaxy component of the color excess E(B?V).The host galaxy is a spiral galaxy and the supernova is highly reddened by the galaxy dust lane.By means of an empirical relation between the equivalent width(EW)of the Na i D lines and E(B?V) (Barbon et al.1990;Richmond et al.1994;Turatto,Benetti,&Cappellaro2003)we estimated E(B?V)?0.15?0.5(A V?0.46?1.55),where the two values correspond to two di?erent slopes of the relation found by Turatto,Benetti,&Cappellaro(2003).The colour excess E(B?V)=0.56±0.04derived from the photometric data is consistent with the value obtained from the spectroscopic analysis.The Galactic component of the absorption is quite negligible:A V=0.025(Schlegel,Finkbeiner,&Davis1998).The spectrum of SN2002lk has a very?at bottom Ca II and Si II absorption troughs.The shape of those absorptions suggest that this is a highly asymmetric supernova,like SN2004dt. 4.2.Type II Supernovae SN2002ln and SN2002lo Both Type II SNe are matched with SN1999em as template,a normal Type II Plateau (Elmhamdi et al.2003).The phase is not so well de?ned for SN2002ln since the blue part of the spectrum has a low S/N.A comparison of SN2002ln with SN1999em at9, 14(Hamuy et al.2001),and24(Leonard et al.2002)days since B maximum,shown in Fig.14,suggests a phase of about2weeks.The Hαminimum is not measurable,the peak of the P-Cygni pro?le,in principle expected to be at null velocity,is slower in SN2002ln (～220km s?1for SN2002ln,～2500km s?1for SN1999em). A comparison with SN1999em～35days since B maximum(Leonard et al.2002) shows that SN2002lo is about one month old(Fig.15).The expansion velocity measured from the Hαminimum in SN2002lo(～8980km s?1)is slightly higher than the one measured for SN1999em(～6100km s?1)(Fig.16),while the peak of the P-Cygni pro?le is faster for SN2002lo(～1500km s?1)with respect to SN1999em(～950km s?1).Uncertainties for our measurements are of the order of500km s?1.However Type II Plateau SNe,and Type II SNe in general,are a very heterogeneous class,showing a wide range in the photometric and spectroscopic properties(Patat et al.1994;Filippenko1997). 5.R(Si ii)parameter&Expansion velocities Several diagrams can help us to learn about these intermediate–z SNe Ia as explosions and allow a comparison with the nearby sample.Expansion velocities for Ca ii(3950?A)and Si ii(6355?A)lines have been measured from the blueshift of the lines,as in the local sample. The ratio of the two Si II lines,i.e.Si ii(6355?A)and Si ii(5890?A)de?nes the R(Si ii) parameter as introduced by Nugent et al.(1995).We measure in this exploration the R(Si ii)parameter following these authors:drawing segments between adjacent continuum points of the absorption lines and measuring the di?erence in?ux between the higher excitation transition of the two(those transitions are the4P–5S and the4S–4P).If the photosphere has a higher e?ective temperature Te?,one would expect that the5800?A trough would increase towards higher Te?.The behavior in SNe Ia is,however,twofold at very early phases(Fig.17).In one group,R(Si ii)is seen to increase signi?cantly towards the premaximum,hotter phase.This is found in SNe Ia like SN2002bo and SN2004dt which present signi?cant5800?A troughs compared to the one at6150?A in this premaximum phase,while in another group it is the opposite:R(Si ii)decreases towards the premaximum hotter phase in SNe Ia like SN1990N or stays constant like in SN2003du.Such diversity of behaviors could be linked to the presence of Fe and Co in the outer layers.According to Nugent et al(1995),the Si II lines interact with line blanketing from Fe III and Co III at premaximum when the temperature is high and Fe and Co are substantially present in the outer layers.This e?ect washes out the5800?A trough.The decrease of R(Si ii)at premaximum in SN1990N could be due to Fe and Co in the outer layers,as this supernova showed these elements in the premaximum spectra.The supernovae which behave like SN2004dt and SN2002bo do not have substantial Fe in the outer layers.An independent analysis points in that direction for SN2004dt.In SN2002bo,intermediate–mass elements were most abundant in the outer layers(Stehle et al.2004).The high R(Si ii)is consistent with the expectation of minor line blanketing by FeIII and CoIII. While we have discussed this ratio at premaximum,which could be an indicator of the physics of the outer layers,we have that at maximum the time evolution in R(Si ii)is quite?at,and one can de?ne R(Si ii)max.The blanketing by Fe III and Co III at this epoch is likely negligible as such ionization stages are not found with the lower temperatures at maximum.In that epoch R(Si ii)max correlates well with absolute magnitude:the more luminous the SNe Ia the lower the R(Si ii)max and the fainter the SNe Ia the higher the R(Si ii)max.We have investigated in Figure18the R(Si ii)max ratio versus intrinsic color of the supernova.We?nd that the bluer SNe Ia have smaller R(Si ii)max.We have placed our intermediate z SNe Ia in that Figure and obtained that those intermediate–z SNe Ia are within the trend de?ned by nearby SNe Ia.For consistency of our comparison between the intermediate z sample and the nearby sample,R(Si ii)ratio has been measured in a similar way.In both cases,we follow Nugent et al.(1995)in de?ning the continuum and the minimum of the absorption throughs.The E(B-V)in the nearby sample is measured using the Lira–Phillips relation(Lira1995;Phillips et al.1999)for the tail of the B-V color, which allows to determine the excess E(B–V)by comparison of the tail from30to60days after maximum with the tail of unreddened SNe Ia(the tail in that epoch shows very low dispersion).In the intermediate z SNe Ia,the same has been done when observations after maximum were available and,in the absence of those,we use the color curve for the stretch of the SNeIa(Nobili et al.2003). We have been able to measure R(Si ii)max for all the SNe Ia found at maximum.In our sample,spectra of two of the SNe Ia were taken one week or more after maximum. Then the Si II5800?A trough is replaced by iron lines and R(Si ii)max can not be measured. In the premaximum SN2002lq the S/N level does not allow to measure this ratio.It has been possible to obtain a good measurement of this ratio for SN2002lk and SN200lp and measured with larger error bars for SN2002li(see Table4).Fig.17shows the ratio R(Si ii) of the depth of the Si ii5972and Si ii6355?A absorption troughs(see Nugent et al.1995; Benetti et al.2005).SN2002lp and SN2002lk show remarkable high R(Si ii)values a few days before maximum in consistency with what is found for red,faint SNIa.SN2002li has values for R(Si ii)max consistent with what is found from SNe Ia of the same brightness in the nearby sample. 6.Discussion The spring run of the ITP2002on SNe Ia for Cosmology and Physics gave6Type Ia SNe,2Type II SNe,7quasars and2Seyfert galaxies.The redshift range of all the sample is0.033≤z≤2.89while the SN redshift range is0.033≤z≤0.329.As expected in a magnitude–limited survey,the peak in the redshift distribution of Type II SNe is closer than the peak in redshift of Type Ia SNe.On the other hand,QSO are observed up to very high–redshift(Fig.19). Our sample allowed a careful inspection of SNeIa.We have made a comparison of the kinematic and temperature observables in these intermediate–z SNe Ia with those of the nearby sample.Some SNe Ia were intrinsically red and,as in the nearby sample,showed a large(～0.5near maximum)R(Si ii)max ratio.Other SNe Ia were bluer with(B?V)0< 0near maximum light.Those showed a small R(Si ii)max ratio(～0–0.2near maximum), as in the nearby sample.Amongst the intrinsically red SNe Ia,also called cool SNeIa,we ?nd SN2002lk and SN2002lp.Those cool SNe Ia are similar to SN1986G but with less extreme characteristcs(higher expansion velocity,slower decline rate of the B light curve). SN2002lp is a cool SNIa similiar to SN1989B.It is a SNIa in between SN1989B and SN1986G.It has a deeper Si ii～5800?A line and larger R(Si ii)max than SN1989B.Both SN 2002lk and SN2002lp show a similar R(Si ii)value(～0.5).SN2002lk and SN2002lp have some other common characteristics:they have the largest?m15(B),they are the closest and the faintest Type Ia SNe.Such trend is in accordance with what could happen under cosmological selection e?ects. The interesting aspect shown here is that the intrinsic faintness of the two SNe Ia is not only revealed by a low stretch factor,i.e.high?m15(B),but also from the large R(Si ii) values(Nugent et al.1995;Benetti et al.2005)which correlate with intrinsic color(see Fig.18),This fact opens new avenues for a better control over reddening in SNe Ia samples gathered in cosmological surveys. The expansion velocities measured for all the SNe Ia in this intermediate z sample are consistent with the values measured for nearby SNe(Fig.20). From Table3we observe that most Type Ia SNe are in spiral galaxies.The2Type II observed exploded in spiral galaxies as well.The fraction of Type Ia exploded in spirals amounts to83per cent if we take into account the uncertain classi?cation of the host galaxy of SN2002lp and SN2002lr.Even if limited by the small statistics and by rough discrimination between spheroidal and spiral galaxies,our result is consistent with the ones derived in a similar redshift range by Valenti et al.(2005)and Balland et al.(2006)(94 and83per cent of Type Ia host galaxies are respectively classi?ed as spirals).These values 第一篇、教你学会看电路图轻松修手机 一、一套完整的主板电路图，是由主板原理图和主板元件位置图组成的。 1.主板原理图，如图： 2.主板元件位置图，如图： 主板元件位置图的作用：是方便用户找到相应元件所在主板的正确位置。而主板原理图是让用户对主板的电路原理有所了解，知道各个芯片的功能，及其线路的连接。 二、相关名词解释 电路图中会涉及到许多英文标识，这些标识主要起到了辅助解图的作用，如果不了解它们，根本不知道他们的作用，也就根本不可能看得懂原理图。所以在这里我们会将主要的英文标识进行解释。希望大家能够背熟记熟，同时希望大家多看电路图，对不懂的英文及时查找记熟。 如图： 以上英文标识在电路图上会灵活出现，比如“扬声器”是“SPEAKER” ，它的缩写就是“SPK”，“正极”是“positive” ，缩写是“P” ，那么如果在图中标记SPKP，那么就证明它是扬声器正极。所以当有英文不明白的时候，可以将它们拆开后再进行理解，请大家灵活运用。 第二节主板元件位置图 一、元件编号 每一个元件在主板元件位置图中，都有一个唯一的编号。这个编号由英文字母和数字共同组成。编号规则可以分成以下几类： 芯片类：以U 为开头，如CPU U101 接口类：以J 为开头，如键盘接口J1202 三极管类：以Q 为开头，如三极管Q1206 二级管类：以D 为开头，如二极管D1102 晶振类：以X 为开头，如26M 晶体X901 电阻类：以R 或VR（压敏电阻）为开头，如电阻R32 VR211 电容类：以C 为开头，如电容C101 电感类：以L 为开头，如电感L1104 侧键类：以S 为开头，如侧键S1201 电池类：以 B 为开头，如备用电池B201 屏蔽罩：以SH 为开头，如屏蔽罩SH1 振动器：以M 为开头，如振子M201 还有一部分标号是主板上的测试点，以TP 为开头。 二、查找元件功能 用户可以根据相应的元件编号去查找主板原理图，从而了解此元件的作用。随便拿块主板作为示例。 如果想了解某一个元件的主要功能（图中红圈内元件） 如图： 第二部分原理篇 第一章手机的功能电路 ETACS、GSM蜂窝手机是一个工作在双工状态下的收发信机。一部移动电话包括无线接收机(Receiver)、发射机(Transmitter)、控制模块(Controller)及人机界面部分(Interface)和电源(Power Supply)。 数字手机从电路可分为，射频与逻辑音频电路两大部分。其中射频电路包含从天线到接收机的解调输出，与发射的I/Q调制到功率放大器输出的电路；逻辑音频包含从接收解调到，接收音频输出、发射话音拾取(送话器电路)到发射I/Q调制器及逻辑电路部分的中央处理单元、数字语音处理及各种存储器电路等。见图1-1所示 从印刷电路板的结构一般分为：逻辑系统、射频系统、电源系统，3个部分。在手机中，这3个部分相互配合，在逻辑控制系统统一指挥下，完成手机的各项功能。 图1-1手机的结构框图 注：双频手机的电路通常是增加一些DCS1800的电路,但其中相当一部分电路是DCS 与GSM通道公用的。 第二章射频系统 射频系统由射频接收和射频发射两部分组成。射频接收电路完成接收信号的滤波、信号放大、解调等功能；射频发射电路主要完成语音基带信号的调制、变频、功率放大等功能。手机要得到GSM系统的服务,首先必须有信号强度指示,能够进入GSM网络。手机电路中不管是射频接收系统还是射频发射系统出现故障,都能导致手机不能进入GSM网络。 对于目前市场上爱立信、三星系列的手机,当射频接收系统没有故障但射频发射系统有故障时,手机有信号强度值指示但不能入网；对于摩托罗拉、诺基亚等其他系列的手机,不管哪一部分有故障均不能入网,也没有信号强度值指示。当用手动搜索网络的方式搜索网络时,如能搜索到网络,说明射频接收部分是正常的；如果不能搜索到网络,首先可以确定射频接收部分有故障。 而射频电路则包含接收机射频处理、发射机射频处理和频率合成单元。 第一节接收机的电路结构 移动通信设备常采用超外差变频接收机，这是因为天线感应接收到的信号十分微弱,而鉴频器要求的输人信号电平较高,且需稳定。放大器的总增益一般需在120dB以上,这么大的放大量,要用多级调谐放大器且要稳定,实际上是很难办得到的，另外高频选频放大器的通带宽度太宽,当频率改变时,多级放大器的所有调谐回路必须跟着改变，而且要做到统一调谐, 一，手机原理图的种类： 手机电路图共分四类：1，方框图；2，整机电原理图；3，元件排列图；4，彩图。 1，方框图： 利用方块形式粗略概述手机的结构与工作原理，方便初学者掌握手机的结构与工作原理，为初学者读懂电原理图打下基础。 2，整机电原理图： 利用电子原件符号清楚表示手机中各元器件的连接和工作原理，方便维修时分析电路原理及故障分析。 3，元件排列图： 利用元件编号在板位图上标明元件所在位置，方便维修时寻找元件在板上的位置。 4，彩图： 即手机照片，方便维修时对照板元件缺损，错位，元件方向。 二，手机电路图的读解原则： 1，读图前要打好电子基础，熟悉各种电子元器件符号，特性和用途；电子元器件在电路中的接法；电路中的电流，电压，电阳之间的关系（欧姆定律）。 2，先读懂方框图，大根了解本机的结构（如那种电源结构，那种时钟结构）；然后按所学的原理去分析原理图。 3，读图时先弄懂直流供电电路，后弄懂交流信号通路。 4，手机电路图是有规律的，一般电源居左下；控制居右下。左射频右逻辑；上收下发中本振。三，手机电路图的读解方法： 1，电源电路读图要点： 1），先了解本机属那种电源结构（分三种）以电源集成为核心。 2），从尾插或电池脚开始，找出电池电压（VBATT，B+）输入线；电池电压一般直接供到电源集成块，充电集成块，功放，背光灯，振铃，振动等电路；也可从上述电路回找。 3），在电源集成块，键盘，内联座处找到开机触发线（ON/OFF或标有开关符号）。 4），在电源集成块上找出各路电压输出线（包括电压走向，电压值多少，是恒定的还是跳变的，在那个单元上可以测到该电压）。 1）VDD--逻辑电压给CPU，字库，暂存等电路（1。8V/2。8V） 2）SYN-VCC（XVCC）时钟电压，使13M电路工作（2。8V） 3）AVCC--音频电压（2。8V） 4）VREF--中频电压（2。8V跳变） 5）3VTX--发射电压（3V跳变） 6）SYN-VCC---频合电压（2。8V） 7)VRTC--实时时钟电压（3V） 8）SIM-VCC--SIM卡电路电压（3V/5V跳变） 9）RST（PURX）--复位信号（0-2。8V） 4），在CPU与电源集成块间找到开机维持线（WD-CP，WATCCH DOG）。 5），从键盘，电源集成块旁边的开关符号到CPU找到关机检测线。 2），充电电路读图要点： 1），以电源集成块或充电集成为核心，找到充电电路。 2），从充电接口（尾插）到电源集成块或充电集成块找出外电输入线 手机供电电路结构和工作原理 一、电池脚的结构和功能。 目前手机电池脚有四脚和三脚两种：（如下图） 正温类负正温负 极度型极极度极 脚脚脚 （图一）（图二） 1、电池正极（VBATT）负责供电。 2、TEMP：电池温度检测该脚检测电池温度；有些机还参与开机，当用电池能开机，夹正负极不能开机时，应把该脚与负极相接。 3、电池类型检测脚（BSI）该脚检测电池是氢电或锂电，有些手机只 认一种电池就是因为该电路，但目前手机电池多为锂电，因此，该脚省去便为三脚。 4、电池负极（GND）即手机公共地。 二、开关机键: 开机触发电压约为2.8-3V(如下图)。 内圆接电池正极外圆接地;电压为0V。 电压为2.8-3V。 触发方式 ①高电平触发：开机键一端接VBAT，另一端接电源触发 脚。 （常用于：展讯、英飞凌、科胜讯芯片平台） ①低电平触发：开机键一端接地，另一端接电源触发脚。 （除以上三种芯片平台以外，基本上都采用低电平触发。如：MTK、AD、TI、飞利浦、杰尔等。） 三星、诺基亚、moto、索爱等都采用低电平触发。 三、手机由电池直接供电的电路。 电池电压一般直接供到电源集成块、充电集成块、功放、背光灯、振铃、振动等电路。在电池线上会并接有滤波电容、电感等元件。该电路常引起发射关机和漏电故障。 四、手机电源供电结构和工作原理。 目前市场上手机电源供电电路结构模式有三种； 1、 使用电源集成块（电源管理器）供电；（目前大部分手机都使用该电路供电） 2、 使用电源集成块（电源管理器）供电电路结构和工作原理：（如下图） 电池电压 逻辑电压(VDD) 复位信号(RST) 射频电压(VREF) VTCXO 26M 13M ON/OFF AFC 开机维持 关机检测 （电源管理器供电开机方框图） 1）该电路特点： 低电平触发电源集成块工作； 把若干个稳压器集为一个整体，使电路更加简单； 把音频集成块和电源集成块为一体。 2）该电路掌握重点: 电 源 管 理 器 CPU 26M 中频 分频 字库 暂存 两小时学会看懂手机电路图 电路图的种类 常见手机维修中的电子电路图有原理图、方框图、元件分布图、装配图和机板图等 (1)原理图 原理图就是用来体现电子电路的工作原理的一种电路图，又被叫做"电原理图"。这种图，由于它直接体现了电子电路的结构和工作原理，所以一般用在设计、分析电路中。分析电路时，通过识别图纸上所画的各种电路元件符号，以及它们之间的连接方式，就可以了解电路的实际工作时情况。原理图又可分为整机原理图，单元部分电路原理图，整机原理图是指手机所有电路集合在一起的分部电路图。 (2)方框图(框图) 方框图是一种用方框和连线来表示电路工作原理和构成概况的电路图。从根本上说，这也是一种原理图，不过在这种图纸中，除了方框和连线，几乎就没有别的符号了。它和上面的原理图主要的区别就在于原理图上详细地绘制了电路的全部的元器件和它们的连接方式，而方框图只是简单地将电路 (3)元件分布图 它是为了进行电路装配而采用的一种图纸，图上的符号往往是电路元件的实物的外形图。我们只要照着图上画的样子，这种电路图一般是供原理和实物对照时使用的。 (4)机板图 机板图的是"印刷电路板图"或"印刷线路板图"，它和元件分布图其实属于同一类的电路图，都是供原理图联系实际电路使用的。 印刷电路板是在一块绝缘板上先覆上一层金属箔，再将电路不需要的金属箔腐蚀掉，剩下的部分金属箔作为电路元器件之间的连接线，然后将电路中的元器件安装在这块绝缘板上，利用板上剩余的金属箔作为元器件之间导电的连线，完成电路的连接。由于铜的导电性能不错，加上相关技术很成熟，所以在制作电路板时，大多用铜。所以，印刷电路板又叫"覆铜板"。但是大家也要注意到：机板图的元件分布往往和原理图中大不一样。这主要是因为，在印刷电路板的设计中，主要考虑所有元件的分布和连接是否合理，要考虑元件体积、散热、抗干扰、抗耦合等等诸多因素，综合这些因素设计出来的印刷电路板，从外观看很难和原理图完全一致；而实际上却能更好地实现电路的功能。 随着科技发展，现在印刷线路板的制作技术已经有了很大的发展；除了单面板、双面板外，还有多面板， 专门找了几个例子，让大家看看。自己也一边学习。 分析一个电源，往往从输入开始着手。220V交流输入，一端经过一个4007半波整流，另一端经过一个10欧的电阻后，由10uF电容滤波。这个10欧的电阻用来做保护的，如果后面出现故障等导致过流，那么这个电阻将被烧断，从而避免引起更大的故障。右边的4007、4700pF电容、82KΩ电阻，构成一个高压吸收电路，当开关管13003关断时，负责吸收线圈上的感应电压，从而防止高压加到开关管13003上而导致击穿。13003为开关管(完整的名应该是MJE13003)，耐压400V，集电极最大电流1.5A，最大集电极功耗为14W，用来控制原边绕组与电源之间的通、断。当原边绕组不停的通断时，就会在开关变压器中形成变化的磁场，从而在次级绕组中产生感应电压。由于图中没有标明绕组的同名端，所以不能看出是正激式还是反激式。 不过，从这个电路的结构来看，可以推测出来，这个电源应该是反激式的。左端的510KΩ为启动电阻，给开关管提供启动用的基极电流。13003下方的10Ω电阻为电流取样电阻，电流经取样后变成电压(其值为10*I)，这电压经二极管4148后，加至三极管C945的基极上。当取样电压大约大于1.4V，即开关管电流大于0.14A时，三极管C945导通，从而将开关管13003的基极电压拉低，从而集电极电流减小，这样就限制了开关的电流，防止电流过大而烧毁(其实这是一个恒流结构，将开关管的最大电流限制在140mA左右)。 变压器左下方的绕组(取样绕组)的感应电压经整流二极管4148整流，22uF电容滤波后形成取样电压。为了分析方便，我们取三极管C945发射极一端为地。那么这取样电压就是负的(-4V左右)，并且输出电压越高时，采样电压越负。取样电压经过6.2V稳压二极管后，加至开关管13003的基极。前面说了，当输出电压越高时，那么取样电压就越负，当负到一定程度后，6.2V稳压二极管被击穿，从而将开关13003的基极电位拉低，这将导致开关管断开或者推迟开关的导通，从而控制了能量输入到变压器中，也就控制了输出电压的升高， EXPRESS WRITTEN PERMISSION OF QUALCOMM. ITS CONTENTS REVEALED IN ANY MANNER TO OTHERS WITHOUT THE NOT TO BE USED, COPIED, REPRODUCED IN WHOLE OR IN PART, NOR U.S.A. San Diego, CA 92121-17145775 Morehouse Drive QUALCOMM Incorporated Sheet # Content 01A. Table of Content 01B. Revision History 01C. Block Diagram 01D. GPIO Map 02. PM8916 Control and MPP/Clock 03. PM8916 Charging 04. PM8916 GPIO/MPP 05. PM8916 Buck converter 06. PM8916 LDO circuits 07. PM8916 CODEC 08. MSM8916 Control 09. MSM8916: EBI 10. MSM8916: GPIO 11. MSM8916: MIPI and RF Control 12. MSM8916: POWER113. MSM8916: POWER214. MSM8916:GND 15. MEMORY:LPDDR3+EMMC 16. Battery Connector 17. Subboard Connector 18. Mic and Receiver 19. EARPHONE 20. LCD interface and backlight 21. Main/Slave Camera and Flash 22. Sensors 23. SIM/TF card 27. WTR1605L TX 28. WTR1605L RX 29. WTR1605L POWER 30. WTR1605L POWER DISTRIBUTION 31. LTE/W/TD/GSM Antenna Switch 32. TRX_Front-High Band QFE234033. TRX_Front-Low Band QFE232034. RESERVED 35. TRX_UMTS_B1/2/5/836. PRX_B34/39/337. PRX_LTE_HB 38. DRX_Antenna Switch 39. QFE1550 DRX Tunner 40. B7/40/41 DRX Switch 41. B39/B1/B3 DRX Switch 42. WTR2605_SECONDARY PATH 43. WTR2605_POWER DISTRIBUTION 44. Antenna_SECONDARY PATH 45. RESERVED 46. RESERVED 47. CDMA BC0(Voice) TRX 48. ET_APT 50. WIFI FEM Sheet # Content 51. GPS/XO DISTRIBUTOR 52. NFC 49. WCN362024. Keypad/LED/Status indicator 25. Touch Interface 26. Test Point/GND/Shields A B C D D C B A 第一篇、教你学会看电路图轻松修手机My id：42409 My name：Aerlant 既然是教程就不能保证100%是原创,难免会引用老师们的宝贵经验，请您别介意哦！ 只要您认真学习完这些教程，就可以正式步入“专业手机维修”行业成为一名优秀的维修员喽！目的很简单，就是让新会员们、新手们，您加入帅虎论坛是正确的。在这里你可以学习到一些实实在在的维修知识，向更高的一个层次迈进、稳步成长。。。 言归正传！有兴趣的朋友往下看，学习一下： 第一节了解电路图 一、一套完整的主板电路图，是由主板原理图和主板元件位置图组成的。 1.主板原理图，如图： 2.主板元件位置图，如图： 主板元件位置图的作用：是方便用户找到相应元件所在主板的正确位置。而主板原理图是让用户对主板的电路原理有所了解，知道各个芯片的功能，及其线路的连接。 二、相关名词解释 电路图中会涉及到许多英文标识，这些标识主要起到了辅助解图的作用，如果不了解它们，根本不知道他们的作用，也就根本不可能看得懂原理图。所以在这里我们会将主要的英文标识进行解释。希望大家能够背熟记熟，同时希望大家多看电路图，对不懂的英文及时查找记熟。 如图： 以上英文标识在电路图上会灵活出现，比如“扬声器”是“SPEAKER” ，它的缩写就是“SPK”，“正极”是“positive” ，缩写是“P” ，那么如果在图中标记SPKP，那么就证明它是扬声器正极。所 以当有英文不明白的时候，可以将它们拆开后再进行理解，请大家灵活运用。 第二节主板元件位置图 一、元件编号 每一个元件在主板元件位置图中，都有一个唯一的编号。这个编号由英文字母和数字共同组成。编号规则可以分成以下几类： 芯片类：以U 为开头，如CPU U101 接口类：以J 为开头，如键盘接口J1202 三极管类：以Q 为开头，如三极管Q1206 二级管类：以D 为开头，如二极管D1102 晶振类：以X 为开头，如26M 晶体X901 电阻类：以R 或VR（压敏电阻）为开头，如电阻R32 VR211 电容类：以C 为开头，如电容C101 电感类：以L 为开头，如电感L1104 侧键类：以S 为开头，如侧键S1201 电池类：以 B 为开头，如备用电池B201 屏蔽罩：以SH 为开头，如屏蔽罩SH1 振动器：以M 为开头，如振子M201 还有一部分标号是主板上的测试点，以TP 为开头。 二、查找元件功能 用户可以根据相应的元件编号去查找主板原理图，从而了解此元件的作用。随便拿块主板作为示例。 第一篇、教你学会看电路图轻松修手机 既然是教程就不能保证100%是原创,难免会引用老师们的宝贵经验，请您别介意哦！ 只要您认真学习完这些教程，就可以正式步入“专业手机维修”行业成为一名优秀的维修员喽！目的很简单，就是让新会员们、新手们，您加入帅虎论坛是正确的。在这里你可以学习到一些实实在在的维修知识，向更高的一个层次迈进、稳步成长。。。 言归正传！有兴趣的朋友往下看，学习一下： 第一节了解电路图 一、一套完整的主板电路图，是由主板原理图和主板元件位置图组成的。 1.主板原理图，如图： 2.主板元件位置图，如图： 主板元件位置图的作用：是方便用户找到相应元件所在主板的正确位置。而主板原理图是让用户对主板的电路原理有所了解，知道各个芯片的功能，及其线路的连接。 二、相关名词解释 电路图中会涉及到许多英文标识，这些标识主要起到了辅助解图的作用，如果不了解它们，根本不知道他们的作用，也就根本不可能看得懂原理图。所以在这里我们会将主要的英文标识进行解释。希望大家能够背熟记熟，同时希望大家多看电路图，对不懂的英文及时查找记熟。 如图： 以上英文标识在电路图上会灵活出现，比如“扬声器”是“SPEAKER” ，它的缩写就是“SPK”，“正极”是“positive” ，缩写是“P” ，那么如果在图中标记SPKP，那么就证明它是扬声器正极。所以当有英文不明白的时候，可以将它们拆开后再进行理解，请大家灵活运用。 第二节主板元件位置图 一、元件编号 每一个元件在主板元件位置图中，都有一个唯一的编号。这个编号由英文字母和数字共同组成。编号规则可以分成以下几类： 芯片类：以U 为开头，如CPU U101 接口类：以J 为开头，如键盘接口J1202 三极管类：以Q 为开头，如三极管Q1206 二级管类：以D 为开头，如二极管D1102 晶振类：以X 为开头，如26M 晶体X901 电阻类：以R 或VR（压敏电阻）为开头，如电阻R32 VR211 简单手机电路图.txt我自横刀向天笑，笑完我就去睡觉。你的手机比话费还便宜。路漫漫其修远兮，不如我们打的吧。 1、方框图： 利用方块形式粗略概述手机的结构与工作原理，方便初学者掌握手机的结构与工作原理，初学者读懂电原理图打下基础 2、整机电原理图： 利用电子元件符号清楚表示手机中各元器件的连接和工作原理，方便维修时分析电路原理及故障 3、元件排列图： 利用元件编号在板位图上标明元件所在方便维修时寻找元件在机板上的位置。 4、彩图： 即手机照片，方便维修时对照机板元件缺损、错位 二、手机电路图的读解原则： 1、读图前先要打好电子基础，熟悉各种电子元件符号、特性和用途；电子元件在电路中的接法 2、先读懂方框图，大概了解本机的结构（如用哪种电源结构、哪种时钟电路）；然后按所学的原理去分析原理图。 3、读图时应先弄懂直流供电电路，后弄懂交流信号通路。 4、手机电路图是有规律的，一般电源居左下；控制居右下。左射频右逻辑；上收下发中本振。 三、手机电路图的读解方法： 1、电源电路读图要点： 1）、先了解本机属哪种电源结构（分三种）;以电源集成块为核心。 2）、从尾插或电池脚开始，找出电池电压（VBATT、B+）输入线；电池电压一般直接供到电源集成块、充电集成块、功放、背光灯、振铃、振动等电路；也可从上述电路往回找。 3）、在电源集成块、键盘、内联座处找到开机触发线（ON/OFF或标有开关符号）。 4）、在电源集成块上找出各路电压输出线（包括电压走向、电压值多少、是恒定的还是跳变的、在哪个元件上可测到该电压）。 1）VDD——逻辑电压给CPU、字库、暂存等电路（1.8V/2.8V） 2）SYN-VCC（XVCC）时钟电压，使13M电路工作（3.8V） 3）AVCC——音频电压(2.8V) 4）VREF—中频电压(2V跳变) 5）3VTX—发射电压(3V跳变) 6）SYN-VCC—频合电压 7）VRTC—实时时钟电压 8)SIM-CC—SIM电路电压（3V/5V跳变） 9）RST（PURX）——复位信号（2.8V） 4）、在CPU与电源集成块间找到开机维持线（WD-CP、WATCCH G）。 5）、从键盘、电源集成块旁边的开关符号到CPU找到关机检测线。 2）、充电电路读图要点： 1）、以电源集成块或充电集成块为核心，找到充电电路。 2）、从充电接口（尾插）到电源集成块或充电出外电输入线 3）、从外电输入线（DC-IN）9到CPU（或电源）找到充电检测线（CHECK）。 4）、从CPU（或电源）到充电集成块找到充电开关控制线（CHARG-ON）。 5）、从充电集成块（或电源）到电池脚（VBATT）找到充电压输出线。教你学会看手机电路图轻松修手机
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