Electronic – Standard packages for compact SMT crystals


There is an old and bog standard form factor for SMT crystals – HC49/US.enter image description here
The problem is that HC49/US takes a lot of real estate on the board. It's 12mm long.

Another problem with crystals and oscillators in general is that they often become long lead time items. [This is my experience.]

There are lots of small form factor crystals from various manufacturers. But, at a glance, it seems that there is no standardization of form factor. It’s nice when packages are standardized. It alleviates the long lead time problem. Crystals from manufacturer B may be used, if crystals from manufacturer A are out of stock.

Are there standard form factors for compact SMT crystals?


Armed with the insights from Gribo and Gustavo, I did a more focused survey. Found that 12MHz in 3.2×2.5mm package are produced by: Abracon, Citizen, Epson, Fox, ECS, TCS, NDK. To be included in this list, the part had to be in stock at DigiKey. It turns out that 3.2×2.5mm package is common across many manufacturers.

Best Answer

There are few common packages for crystals. For 4 pad variants, there is 5x7mm, 3.2x2.5mm 2.5x1.6mm and few others. They are available from many different manufacturers and share a common pinout.

For 32.768KHz crystal (Very common in microcontroller based designs) there is a common package from Citizen (Watches) that is used by many other manufacturers, but I dont know its dimensions off hand.