DreaM117er shared his Paicorea, an ultra-thin split keyboard built with PG1316S switches. It is driven by RP2040 Core-A controllers and features an optional Azoteq TPS43 trackpad.
I derived the name Paicorea from the MCU: “Pi” (from RP2040, Raspberry Pi) and “Core-A” — forming Pai-corea, hence, Paicorea was born – DreaM117er.
The initial concept followed designs like the AZCARD, Bayleaf, and Mikefive, which use PG1316S switches and compress the body to around 3 mm thick by using the PCB as the bottom plate. However, since DreaM117er isn't a big fan of wireless devices, he insisted on including a 3.5mm TRRS jack, common in split keyboards, so the keyboard's thickness is about 5.5mm.
Specs
42 keys (6x3+3)
35g PG1316S switches, SMD
RP2040 Core-A MCU
Azoteq TPS43 trackpad
The author spent a lot of time looking for suitable low-profile parts and eventually found three usable 3.5mm TRRS jack models: PJ-381B, PJ-381C, and PJ-399. Based on their datasheets and 3D models, he chose to use the PJ-381B.