An adapter isn't going to help if OnSemi's suggested substitute is useless as a VAS transistor.
I received a few quotes for KSA1381E, but the prices are very high. $0.70 to $1.00 per piece + shipping. Add to that another $0.20 for authenticity testing.
With KEC1381 readily available, it doesn't seem to make much sense to continue pursuing this at the prices I am seeing.
For those that contacted me, I'll work on getting the 2SC3503E shipments out this week.
With KEC1381 readily available, it doesn't seem to make much sense to continue pursuing this at the prices I am seeing.
For those that contacted me, I'll work on getting the 2SC3503E shipments out this week.
Brian,
Thanks for the reply. So for us that have paid for both, but have not had any shipped, can the KEC1381 be used with the 2SC3503E ?. If so, are you going to order the KEC1381's for us and then deliver with the original 2SC3503E.
Just trying to keep organized in my old age 😉
MM
Thanks for the reply. So for us that have paid for both, but have not had any shipped, can the KEC1381 be used with the 2SC3503E ?. If so, are you going to order the KEC1381's for us and then deliver with the original 2SC3503E.
Just trying to keep organized in my old age 😉
MM
There are no US-based KEC distributors and no luck on procuring a KEC KTA1381-Y bulk order direct from KEC. I reached out to KEC many times but I have yet to receive a reply. Ordering from Profusion would be the next best option; they do offer reasonable discounts for large quantities. This might make sense for GB participants in the US. However, for European participants, I think shipping and tariffs will likely make it more expensive than buying direct.
The Onsemi/Fairchild/Sanyo devices should be compatible with KEC devices. The curves on the datasheets are very similar. I cannot say how closely they will match for gain. Even within the Onsemi/Fairchild/Sanyo lines, I understand that the fully-encapsulated OnSemi devices won't match to the earlier exposed collector Fairchild/Sanyo devices as well as pairs of devices from the same generation. Meaning, if you are looking for gain matched devices, the yield will likely be lower depending how how close of a match you are looking for. Probably the same for 2SC3503E & KTA1381Y. Having said this, many designs won't need matched devices in the VAS or driver positions. Complimentary pairs will usually suffice.
The Onsemi/Fairchild/Sanyo devices should be compatible with KEC devices. The curves on the datasheets are very similar. I cannot say how closely they will match for gain. Even within the Onsemi/Fairchild/Sanyo lines, I understand that the fully-encapsulated OnSemi devices won't match to the earlier exposed collector Fairchild/Sanyo devices as well as pairs of devices from the same generation. Meaning, if you are looking for gain matched devices, the yield will likely be lower depending how how close of a match you are looking for. Probably the same for 2SC3503E & KTA1381Y. Having said this, many designs won't need matched devices in the VAS or driver positions. Complimentary pairs will usually suffice.
Brian, instead of shipping just what you have on hand, would you be willing to use funds already sent to procure a bulk KTA1381Y order from Profusion. I'm willing to wait if you are willing to do that. I very much appreciate all your efforts.
available in profusion at the moment more than 20k pairs , it is now time to buy. but i think they will evaporate soon, like in january
Thanks to @birdbox for doing some homework on procuring KEC KTA1381Y devices.
We can order up to 4,000 devices from Profusion and avoid tariffs (it's based on the order total staying under $800). With shipping, it comes out to just under $0.20 each. With the volume discounts, that is less that what we would have paid to Mouser for the Onsemi KSA1381E. 4000 covers just about everyone that joined the GB.
If that works for everyone, I'll place the order tonight. If you are not interested please PM me.
Hopefully we can button up this GB with a modicum of success.
We can order up to 4,000 devices from Profusion and avoid tariffs (it's based on the order total staying under $800). With shipping, it comes out to just under $0.20 each. With the volume discounts, that is less that what we would have paid to Mouser for the Onsemi KSA1381E. 4000 covers just about everyone that joined the GB.
If that works for everyone, I'll place the order tonight. If you are not interested please PM me.
Hopefully we can button up this GB with a modicum of success.
Thanks Brian, that works for me! I really appreciate all your efforts with this.
I recently bought 100 KTC3503Y from Profusion and they turned out to be an almost perfect gain match ( ~137-140) for the Onsemi KSA1381E that I already had. Posted in case the info might be of use to others. Incidentally I have noticed that the datasheet hFE vs Ic curves for transistors often correspond to the highest yield hFE devices within a gain group. This then gives a fair idea of the hFE for the devices that you are likely to receive. I haven't done a study of any number of devices/datasheets but its worked often enough to be useful for me.
De-committing at least for the time being. If you need me added to an order please confirm first. The reason is that I've risked buying some KSA / 2SA1381-Es on eBay and some of them look like they are probably real. I've ordered a transistor tester to measure beta too. That should give me an idea. I still won't know the output impedance though.