Hi Greg
Agreed. It seems you will soon have a replacements manual here. It's going well with the good contributions.
Unfortunately, dummies like me can't decide betwween them now. There are also some that are not economically viable now too. Logically, the listing needs to be split or the comments on status completed. This will save time searching for unobtanium.
Why not just a simple letter in comments lke O for obsolete etc. so there is still space for actual comment.
Agreed. It seems you will soon have a replacements manual here. It's going well with the good contributions.
Unfortunately, dummies like me can't decide betwween them now. There are also some that are not economically viable now too. Logically, the listing needs to be split or the comments on status completed. This will save time searching for unobtanium.
Why not just a simple letter in comments lke O for obsolete etc. so there is still space for actual comment.
O = obsolete. I like this.
other offerings
X = difficult to source
C = cheap
E = expensive
N = needs cascode (applies to an excellent spec transistor that has insufficient Vce0)
What list would be useful?
other offerings
X = difficult to source
C = cheap
E = expensive
N = needs cascode (applies to an excellent spec transistor that has insufficient Vce0)
What list would be useful?
This is also a good idea. On one hand I observe typical values between 10mA and 20mA for typical small signal devices like BC416/BC560 and arround 3-5 mA for video high voltage devices (BF series).
But on the other hand the difference between the rising and falling edge of the curvature in the diagrams sometimes very large. One extra column with an upper and lower Ic for highest Hfe and Ft therefore is helpful.
Hi,
Will add Iq enhance distortion figure in a pre amp stage? I currently use BC 140 with CCS (SE) run at 0.7 mA only, 30Vpp, with negative feedback. Not sure if it is the most optimum. Considering to increase Iq as long as dissipation is under spec, if it will give better result.
I also consider to replace BC140 with N JFET, but I believe low Iq is not an issue for JFET (CMIIW), just to adjust voltage bias for JFET (vs BJT).
Thx,
Ervin L
0,7mA by the BC140 this is too low value. 20-40 mA delivers max ft.
http://www.datasheetcatalog.org/datasheet/siemens/BC141.pdf
BC140 Datasheet pdf - NPN SILIKON-TRANSISTOREN - Siemens
Start a new thread and post your schematic diagram.
Come on folks, yer gonna drive the man crazy.
Listing a specific Ic for gain peaks is silly. Besides the better devices are more linear or flat Hfe vs. Ic! On the other hand it maybe more useful to find the optimum Ic for the lowest value of Rbb or input noise, not hfe.
I do hope Greg will re-consider some production status or relative price catagory column tho.
Listing a specific Ic for gain peaks is silly. Besides the better devices are more linear or flat Hfe vs. Ic! On the other hand it maybe more useful to find the optimum Ic for the lowest value of Rbb or input noise, not hfe.
I do hope Greg will re-consider some production status or relative price catagory column tho.
Infinia, you are missing the point.
A range of currents for which the device operates near it's claimed performance parameters is a good guide when selecting a device for a particular duty.
Selecting a device and running it at an operating current that is way outside it's near optimum operating range is what would be "silly"
I would never use a To220 Ic=500mAmax device for a VAS duty. Why? Because it is way outside it's optimum operating current range when it passes 3mA to 12mA. If it's optimum current range is 50mA to 120mA then that piece of information tells all.
Hi Andrew,
This exercise has taught me a lot about datasheets....as you point out they use different test conditions to generate their specs. Some are consistent, some are not. Sometimes information is missing. There is also a difference between NPN and PNP specs regarding Cob etc.
The best I can hope for is a ball park guide and then you really have to check the actual datasheet in question. At least my tables will give a bit of a comparison and it should be a convenient location to find datasheets.
regards
Hi,
I have updated the Small Signal Transistors table to improve readability and add a few requested features and columns. I will update the other tables to make things more consistent in due course and after feedback.
Small Signal Transistors
I have changed the style sheet to remove colour and underlining from links. I felt it was making the appearance untidy and making it more difficult to read.
I have added tool tips, so if you move your cursor over some of the areas of the table you should be getting a tool tip giving you an instruction or more information.
The notes column now has abbreviated notes, but a tool tip should give expanded information. LN = Low noise, HB = High beta. The extra notes like LC = Low cost, O = Obsolete, etc will be added here.
Just a word about how I am doing this. These tables are all hand coded html and this does have limitations compared to a database solution. Although the tables look very simple, the html is getting big, about 800 lines. Cutting and pasting errors are going to occur, so reporting errors is important.
regards
I have updated the Small Signal Transistors table to improve readability and add a few requested features and columns. I will update the other tables to make things more consistent in due course and after feedback.
Small Signal Transistors
I have changed the style sheet to remove colour and underlining from links. I felt it was making the appearance untidy and making it more difficult to read.
I have added tool tips, so if you move your cursor over some of the areas of the table you should be getting a tool tip giving you an instruction or more information.
The notes column now has abbreviated notes, but a tool tip should give expanded information. LN = Low noise, HB = High beta. The extra notes like LC = Low cost, O = Obsolete, etc will be added here.
Just a word about how I am doing this. These tables are all hand coded html and this does have limitations compared to a database solution. Although the tables look very simple, the html is getting big, about 800 lines. Cutting and pasting errors are going to occur, so reporting errors is important.
regards
Are you sure of that? LOL
I was talking about small signal devices, where there are more functionality, but if you are talking about drivers and Vas devices, there are separate sheets for each duty there, right. Besides your "point" is still funny IMO. Vas devices can be culled from the driver herd pretty quickly. Looking at Cob and/or Pd for instance will do this without needing superfluous Ic sub groupings. You would not use a high current device not because it's outside of it optimum gain range but mostably a higher current/power device will have Cob outside the limits for Vas duty. Cob > Cdom is quite telling its the wrong part.
Another point - what is the "optimum current range" say for a driver? I see drivers running far beyond the limits of their linear gain all the time. My point being is that these sheets can't be a design tool , at some point you will need to compare curves on data sheets. yes?
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Hi all,
I have added a few more output transistors to the list and corrected a few errors.
The datasheets for some of the transistors were not available at DataSheet4U but I put the links in anyway and sent a request for the datasheets to be added. When testing the datasheet links this morning I found they work, thank you DataSheet4U. 😀
regards
I have added a few more output transistors to the list and corrected a few errors.
- MJ15003/MJ15004
- MJ15024/MJ15025
- NJW0281G/NJW0302G
- NJW3281G/NJW1302G
The datasheets for some of the transistors were not available at DataSheet4U but I put the links in anyway and sent a request for the datasheets to be added. When testing the datasheet links this morning I found they work, thank you DataSheet4U. 😀
regards
Good work, Greg.
Btw, the max gain of 2SC1775/1775A is 1200. Mini is 400;
Ft typ is 200MHZ.
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St (SGS-Thomson) Cross Reference
St (SGS-Thomson) Cross Reference
http://www.st.com/stonline/products/promlit/pdf/sglvbt1007.pdf
St (SGS-Thomson) Cross Reference
http://www.st.com/stonline/products/promlit/pdf/sglvbt1007.pdf
greg, my suggestion is to add noise figure column, where only for transistor which have those value in datasheet. (rarely have, but sometimes help someone finding)
And the ranking there, is it matter much ? and what is it about ?
(small signal transistor and driver section lack those information alot)
But truly it helps alot, although I find out it late.
And the ranking there, is it matter much ? and what is it about ?
(small signal transistor and driver section lack those information alot)
But truly it helps alot, although I find out it late.
Noise figure in the datasheet is generally intended for VHF & RF use.
The graphs can be used for audio noise estimating but even these can't replace actually measuring the noise from your final set up.
ignore noise.
Draw up your own shortlist. Then read the datasheets. You will find some described as designed for audio low noise duty. Listen to other Members when they recommend an audio transistor.
The graphs can be used for audio noise estimating but even these can't replace actually measuring the noise from your final set up.
ignore noise.
Draw up your own shortlist. Then read the datasheets. You will find some described as designed for audio low noise duty. Listen to other Members when they recommend an audio transistor.
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