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MPS4250
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John Woodgate
In message <ks6d15+3s9u@...>, dated Wed, 17 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes:
Can anybody here tell me where I can find a spice model for this PNP ? Thank you;Apart from the packaging, it is similar to a BC556 or BC557. -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk Why is the stapler always empty just when you want it? John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK |
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Hi.
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Look: .MODEL MPS4250 PNP IS =2.01722E-14 NF=1.00872 VAF =55.5699 IKF= 0.108955 ISE = 6.37359E-16 NE =1.35818 BR =4.41291 NR= 1.02097 VAR= 6.54054 IKR = 0.0178791 ISC =2.78089E-14 NC=1.13928 RB = 85.9809 RE= 0.260437 EG=1.11 XTI = 3 CJE= 9.35999p VJE = 0.805219 MJE= 0.390963 VJC = 0.270529 MJC= 0.295929 FC= 0.5 BF =3.213490E+02 CJC = 6.39675p RC=2.2484 TF=1.0E-10 XTF =1 Bordodynov. 17.07.2013, 20:04, "jean_claudeabeille" <jean_claudeabeille@...>: Can anybody here tell me where I can find a spice model for this PNP ? |
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abeill¨¦ jean-claude
OK, thank you John.
?Perhaps you can help me in my quest. I am a french retired computer analyst and a music and electonicsenthusiast. Please, will you excuse my english. For the moment, I try to understand how does work my amp with LTSpice. Actually, after an error in handling, one channel failed and activated a protection circuit (too much quiescent on one output stage polarity). I tried to fix this but I failed and ordered a complete replacement PCB. But I am curious and like to understand things. So I drawn the circuit in LTSpice from the PCB and could not understand it in some places. I asked Bob Cordell some help but he was to busy and answer me to read chapter 1-4 from his book. OK. In fact, in LTSpicen there is almost no quiescent current in output stage and the VBE spreader does not work at all. I thought that some models where not correct but I don't know. I'm deadlocked. Jean-Claude. ________________________________ De?: John Woodgate <jmw@...> ??: LTspice@... Envoy¨¦ le : Mercredi 17 juillet 2013 18h55 Objet?: Re: [LTspice] MPS4250 ? In message <ks6d15+3s9u@...>, dated Wed, 17 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes: Can anybody here tell me where I can find a spice model for this PNP ?Apart from the packaging, it is similar to a BC556 or BC557. -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk Why is the stapler always empty just when you want it? John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK |
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John Woodgate
In message <1374140838.88699.YahooMailNeo@...>,
dated Thu, 18 Jul 2013, abeill¨¦ jean-claude <jean_claudeabeille@...> writes: I am a french retired computer analyst and a music andIt is quite good. For the moment, I try to understand how does work my amp with LTSpice.Please upload the circuit (we use the US term ''schematic' on this list) to Files => Temp on the list's web site: I asked Bob Cordell some help but he was to busy and answer me to readI expect we can help once we see the schematic. -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk Why is the stapler always empty just when you want it? John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK |
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jean_claudeabeille
--- In LTspice@..., John Woodgate <jmw@...> wrote:
OK, I would like it. I sent this text from yahoo mail and never received the answer. Fortunately I found it here. Problem is : I don't know how to join a schematic here while it's easy with yahoo mail. How can I proceed ? |
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John Woodgate
In message <ksdh55+evd7@...>, dated Sat, 20 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes:
OK, I would like it. I sent this text from yahoo mail and never received the answer. Fortunately I found it here. Problem is : I don't know how to join a schematic here while it's easy with yahoo mail. How can I proceed ? Look at these links at the foot of each list message: To upload a schematic, go to the web site and click on 'Files' in the left column. On the Files page, scroll down to 'Temp' in the middle column and click on it. On the Temp page, click on 'Add file' at the top right of the middle column. Use, for example 'MPS4250 model.asc' as the filename. Disregard the part headed 'Auto-send to members' (if it appears) and tick the box under 'Notification'. Then click on the blue 'Upload' box. -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk Why is the stapler always empty just when you want it? John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK |
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John Woodgate
In message <MfjOdgDTQl6RFw$6@...>, dated Sat, 20 Jul 2013, John Woodgate <jmw@...> writes:
In message <ksdh55+evd7@...>, dated Sat, 20 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes:They were stripped out by the server. The important one is: which takes you to the list's site front page. -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk Why is the stapler always empty just when you want it? John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK |
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abeill¨¦ jean-claude
Thank you for the tutorial, I wouldn't have found out in what folder - temp - to store the file.
OK, it's done, file name is AmpJCA.asc. ________________________________ De?: John Woodgate <jmw@...> ??: LTspice@... Envoy¨¦ le : Samedi 20 juillet 2013 11h10 Objet?: Re: [LTspice] Re: MPS4250 ? In message <ksdh55+evd7@...>, dated Sat, 20 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes: OK, I would like it. I sent this text from yahoo mail and never received the answer. Fortunately I found it here. Problem is : I don't know how to join a schematic here while it's easy with yahoo mail. How can I proceed ? Look at these links at the foot of each list message: To upload a schematic, go to the web site and click on 'Files' in the left column. On the Files page, scroll down to 'Temp' in the middle column and click on it. On the Temp page, click on 'Add file' at the top right of the middle column. Use, for example 'MPS4250 model.asc' as the filename. Disregard the part headed 'Auto-send to members' (if it appears) and tick the box under 'Notification'. Then click on the blue 'Upload' box. -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk Why is the stapler always empty just when you want it? John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK [Non-text portions of this message have been removed] |
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John Woodgate
In message <1374329454.5183.YahooMailNeo@...>,
dated Sat, 20 Jul 2013, abeill¨¦ jean-claude <jean_claudeabeille@...> writes: Thank you for the tutorial, I wouldn't have found out in what folder -It is missing the symbol LF353. It is always good to try to run the actual file you intend to upload. Please do that and then upload the LF353 symbol and anything else that proves to be missing. Q14 base doesn't go anywhere. Is that correct? -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk Why is the stapler always empty just when you want it? John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK |
It is missing the symbol for "LF353". That is the error message I get when trying to load your file into LTspice. If your schematic uses any new symbols or models or subcircuits that didn't come with LTspice itself (such as the LF353), then you will need to upload those along with your schematic file, also to the group's "Temp" folder. The recommendation is that you ZIP all the files, with your schematic file (except for .log and .raw files), into one .zip file, and then upload just the .zip file to the Temp folder. I also just noticed: You have a 2N5401C shown as both a PNP and an NPN. I see you also have many unique transistor part numbers, which are not in LTspice's transistor library. Will you also have SPICE models for them? Currently they will not simulate as the part numbers you've given. Regards, Andy |
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--- In LTspice@..., abeill?? jean-claude <jean_claudeabeille@...> wrote:
Hello Jean, The circuit had a lot of mistakes. I tried to correct them. Please watch all the circles and my other comments in the schematic. My files: Files > Temp > AmpJCA_1.zip I have used most of the missing transistor models from bordodynov's file standard.zip. Over all we don't want discuss the design of audio amplifiers in the LTspice Yahoo group. You should do that in DiY-Audio groups. There are also books about audio amplifiers, e.g. this one from Cordell, . Best regards, Helmut |
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jean_claudeabeille
Thank you for your answer, it's very kind
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--- In LTspice@..., ¨¢???????? ?????????¡Á <BordodunovAlex@...> wrote:
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found this old thing ...similar, somebody may want it.
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.model PN4250 PNP(Is=6.734f Xti=3 Eg=1.11 Vaf=45.7 Bf=388.2 Ne=1.806 + Ise=6.734f Ikf=.205 Xtb=1.5 Br=2.635 Nc=2 Isc=0 Ikr=0 Rc=1.67 + Cjc=6.2p Mjc=.301 Vjc=.75 Fc=.5 Cje=7.5p Mje=.2861 Vje=.75 + Tr=9.861n Tf=467.9p Itf=.17 Vtf=5 Xtf=8 Rb=10) * National pid=62 case=TO92 * 88-09-08 bam creation hmmm...don't need the parentheses anymore eh? --- jean_claudeabeille@... wrote: From: "jean_claudeabeille" <jean_claudeabeille@...> To: LTspice@... Subject: [LTspice] Re: MPS4250 Date: Sun, 21 Jul 2013 00:01:32 -0000 Thank you for your answer, it's very kind --- In LTspice@..., ¨¢???????? ?????????¡Á <BordodunovAlex@...> wrote:
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jean_claudeabeille
Hello John
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You are right, there are some errors in the schematic. I uploaded the new corrected one along with the missing components files : AmpJCA.zip. I hope that this time the schematic is correct. Meanwhile I received 2 models of mps4250. Simulations with one of them and with BC557 give very different results. Which one is true ? LTSpice's one - BC557B or BC557C - I guess. In fact results are very dependent of model's parameters. Besides, I don't know if it's important but on my amp, U2 is CNY17-4 which is not present in LTSpice's OPTOS. What I woud like to understand is HOW to equilibrate the voltages at the collectors of Q12 and Q13 to get quite the same current at R101 and R111. --- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:
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jean_claudeabeille
OK, Helmut, if "we don't want discuss the design of audio amplifiers", I give up !
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--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:
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John Woodgate
In message <ksg876+8t42@...>, dated Sun, 21 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes:
What I woud like to understand is HOW to equilibrate the voltages at the collectors of Q12 and Q13 to get quite the same current at R101 and R111.I suggest you follow Helmut's advice, because your question is about amplifier design, not LTspice simulation. -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk Why is the stapler always empty just when you want it? John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK |
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Hello Jean,
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I have uploaded a new version which tries to use most of your original values while still has all the necessary corrections. Please continue with this version in your project. Files > Temp > AmpJCA_1b.zip The LF353 regulates the DC-output voltage to the DC-input voltage. Therefore the opamp adjusts the current of the JFets which changes the voltage drop on R5. Basically it equalize the collector current of Q8 and Q12. This control loop has to be slower then the lower corner frequency of your amplifier. Best regards, Helmut --- In LTspice@..., "jean_claudeabeille" <jean_claudeabeille@...> wrote:
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