Good substitutions for new designs during the chip shortage - Page 1
Forum section: electronics / projects

author: ezalys
author_rank: Frequent Contributor
timestamp: July 27, 2021, 09:54:49 pm
content: For those of us doing new designs, does anyone have any advise about which microcontrollers, regulators, or other components that are sensible to design around during this chip shortage? For instance, the stm32f103 is unobtainium but the atmega8u seems pretty easy to find. Why is this? Does that mean the 8u is a good chip to design around, or does it seem like the shortage will just hit it later? Is this just unknowable? Are there chips that are likely going to be available sooner due to demand? Are certain manufacturers handling the shortage better? Any wisdom is appreciated.

author: ataradov
author_rank: Super Contributor
timestamp: July 27, 2021, 10:05:32 pm
content: F103 and atmega8u have significantly different performance. I'd wager F103 is way more popular because it has much better price/performance ratio.There is no guarantee, anything can go missing, so if you are designing something new, make sure to secure at least a year of supply.

author: ezalys
author_rank: Frequent Contributor
timestamp: July 27, 2021, 10:11:14 pm
content: Oh sure -- totally different chips. I guess I was just wondering if the atmega8u was on an older process node that was easier to get running again, or if it was from a different fab that was able to produce more, or that an auto manufacturer or something (unlikely for a USB microcontroller but you know what I mean) placed a gihugeous order and now there's some flooding the market. Demand though -- yeah probably, but this doesn't yield much predictive information

author: ataradov
author_rank: Super Contributor
timestamp: July 27, 2021, 10:19:27 pm
content: There is no way to guess the reasons for availability of the parts. But also no way to predict the future. U8 may disappear tomorrow.The only way to ensure supply for smaller projects today is to secure the parts first.

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 27, 2021, 10:25:01 pm
content: Uhh.. I guess outside of the hobbyist crowd (and a fraction of it), the atmega8u must not be used much anywhere anymore. It's extremely limited. The STM32F103 has been used and abused pretty much everywhere. Of course the latter will be unobtainium way earlier.You can't compare those. Completely different league. It's almost like comparing a Smart Fortwo and a Dodge Viper.The Atmega8 series was released in 1996. The STM32F103 was launched in 2007. Yeah. Don't know the process node for the Atmega8u but it's probably a significantly older process.There are tons of closer alternatives to the F103. Now availability will still be a bet at this point. Something available today may not be in 3 months. That's a general issue that doesn't have any magic solution that I know of.High demand is on one hand a sign that some chip would know shortage earlier, but OTOH, low demand can mean that it gets very low priority in fabs and thus, you'd only get whatever is still in stock, and after that, it might get worse than high-demand ones...

author: ezalys
author_rank: Frequent Contributor
timestamp: July 27, 2021, 10:31:00 pm
content: I really get that they're incomparable in many ways, but comparable in the sense that if you just need a dumb USB microcontroller to poke some IO lines and maybe have a tiny bit of intelligence they both fit the need. They're different enough that the reasons for their availability or lack thereof is worth comparing.

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 27, 2021, 10:40:20 pm
content: If performance of the Atmega8u is fine for your needs, and you essentially need a small MCU with USB FS support, then you have even more options than looking for something closer to the F103.Just look for MCUs with USB FS on your favorite search engines, on distributor web sites, etc. You'll find hundreds or more.As we said though, availability is just a gamble at this point. If you try to find a secret sauce to be saved from shortage, apart from stocking whatever is available now, you may be in for some disappointment.

author: ezalys
author_rank: Frequent Contributor
timestamp: July 27, 2021, 11:20:57 pm
content: Yeah -- my impression is that one should buy first, design once the parts are secured. Which is fine.

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 27, 2021, 11:45:47 pm
content: Fine but you need the cash.