Do you prefer the narrow or wide (ammo package) lead spacing?
Personally I prefer the wider spacing, especially because it makes it easier when testing and I don't have to spread the leads to get them into the PCB.
Personally I prefer the wider spacing, especially because it makes it easier when testing and I don't have to spread the leads to get them into the PCB.
The leads of the To92 are easily manipulated into any format demanded by the PCB layout designer.
Transistor lead spacing does not matter!
Transistor lead spacing does not matter!
Unless you are inserting thousands of the bastards by machine.
Then what matters is that the lead spacing is the same as on your board 😀
Then what matters is that the lead spacing is the same as on your board 😀
I use 100 mil lead spacing -- the TO-92 devices I prefer are on tape and are spaced with their legs slightly spread. The tape allows you to test them and write down Vbe and hfe.
Why worry about lead spacing on the package? I like wider lead spacing on the pcb because from my experience, I need to run trace between pads. I had to create a new foot print with more spacing and I sure use the space to run traces!!!
FYI, when you create foot print, make the three pads position in a triangle, so you can get more space between pads. In the complementary where you have two LTP input pairs, I had to run two traces under the transistors on the same side. If you layout out the complementary IPS, you'll know exactly what I mean.
FYI, when you create foot print, make the three pads position in a triangle, so you can get more space between pads. In the complementary where you have two LTP input pairs, I had to run two traces under the transistors on the same side. If you layout out the complementary IPS, you'll know exactly what I mean.
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I buy the cheapest one!!! As stated about the footprint, I have to bend the lead no matter what package. Even 100mil spacing is too narrow. Unless you use 50mil pads, 10mil trace with 10ml spacing, you cannot fit two traces between pads. I don't do that unless it is necessary particular if you go for cheap pcb from China.
I do 60mil pads with 35mil drill to make the pads more robust, I use 15mil trace width absolutely minimum with 12 mil spacing between any trace to trace, pads etc. I use all 25mil trace for signal if all possible to increase reliability.
I do 60mil pads with 35mil drill to make the pads more robust, I use 15mil trace width absolutely minimum with 12 mil spacing between any trace to trace, pads etc. I use all 25mil trace for signal if all possible to increase reliability.
I hate pulling transistors off tape, regardless of the lead spacing. And 500 of them take up less room bulk packed than on tape.
I find when removing them from tape I end up with little bits of tape left on which is a pig to remove.
I prefer the footprint to match the transistor exactly or I have to bend legs to fit.
My favourite to92 is MPSA42 and MPSA92, they are high voltage so are good for most amplifier usage.
I prefer the footprint to match the transistor exactly or I have to bend legs to fit.
My favourite to92 is MPSA42 and MPSA92, they are high voltage so are good for most amplifier usage.
I studied a lot about small signal transistor. I don't buy into which one is better like BC556 and 546 are the best etc. I look at fT, capacitance, Vcb and beta to judge. BUT the reason I go with BC's is I want the EBC configuration over the BCE of the KSP and others. It makes a big big difference in layout.....and that's what it really matters in my book. Layout is everything, not all the hear say. I don't care whether it's MPSA, BC or KSP or whatever. It's all about the spec.
AND......AND....the most important of it all. The best OPS is easily about 20dB higher harmonic distortion than any reasonable IPS/VAS!!!! I did enough simulation on many different IPS VAS configuration. Don't worry about the small signal portion as any reasonable design are so much lower distortion than the OPS. Concentrate on the OPS!!! Worry about the layout so you don't have cross couple and instability.
AND......AND....the most important of it all. The best OPS is easily about 20dB higher harmonic distortion than any reasonable IPS/VAS!!!! I did enough simulation on many different IPS VAS configuration. Don't worry about the small signal portion as any reasonable design are so much lower distortion than the OPS. Concentrate on the OPS!!! Worry about the layout so you don't have cross couple and instability.
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when i create my own pcb in old fashion way...i make a triangular holes for the to-92's which will accommodate bot 2S seris and of US series...ecb and ebc types and makes a little bit easy on testing.
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