Been lurking for a while, but this topic hits true with some recent
experiences. I would not hesitate to buy most common digital ICs on Amazon
or ebay, but I usually will not buy analog ICs other than from trusted
sources, such as Mouser. I have bought LM2596 voltage regulators that
oscillate at the wrong frequency (which breaks all the calculations for
selecting the inductor), and I have bought MAX202/MAX232 serial drivers
that burn up in circuit. Switching to official sources cured both of those
problems. You also have to be careful of things like SRAM (for example
AS6C4008) as I have found the cheap ones don't meet the performance of the
ones from Mouser, even though the silkscreen says they're the same
manufacturer and speed. If you're paying more than an order of magnitude
less for something than it sells for on Mouser, it's probably not the same
part.
UTSource used to be good, but I found now commonly engages in bait and
switch. A week after I submit an order, I would get some email claiming a
supply issue and demanding that I submit additional paypal payment for my
order to ship The last order, this happened on two different part numbers,
one went from $14/IC to $50/IC and another part went from $5/IC to $12/IC.
This had happened several times over the last couple months with them.
Maybe they really are having issues with their suppliers (though I swear
this was happening on items where UTSource itself was listed as the
supplier) but that's not really my concern. They were becoming a huge waste
of time and source of frustration. I put them on vacation
Aliexpress is full of fakes, on anything and everything, and sometimes you
have to repeatedly argue to get your money back. eBay is better at siding
with the buyer.
Scott
On Sat, Mar 30, 2024 at 6:22 PM ben via cctalk <cctalk(a)classiccmp.org>
wrote:
On 2024-03-30 6:10 p.m., Jonathan Chapman via cctalk
wrote:
Standard
TTL 74XXX is drying up rather quickly. Futurlec still has some
TTL but 7404s are all gone. Even LS is hard to find.
Ours comes from Mouser, between two part #s they have over 7,000 74LS04s
in DIP packaging in stock. Didn't check ACT, HCT, or ALS. I don't think
we've had a 7400 series part that we couldn't just order off Mouser in
recent history, and we're usually buying QTY 100.
Thanks,
Jonathan
I checked mouser (canada) again. After about 3 pages of garbage matches,
I found some 7904's in DIP packages, only a few 100 in stock.
TI and Motorola sell 74LS541's but only the Motorola part has Vin Low of
.8 volts. TI has .6 Vin low. Are there any more part differences between
TI and other digital logic.