Lard84

About the Lard84 PCB

Lard84 is an open source RP2040/RP2350 PCB design by beulard, published on GitHub under the CC0-1.0 license. It is a 2-layer board measuring 308.8 × 118.3 mm, with 88 components from 5 distinct parts.

Its main chip is the RP2350_Stamp, from the RP2040/RP2350 family. By type, the board carries 85 diodes, 1 IC, 1 connector and 1 resistor.

It belongs with the keyboards designs in this gallery.

From the project

A custom 75% ansi, low-profile keyboard.

- PCB - Plate - Case - Acknowledgments - Extra pictures

The assembly is done in (sort of) sandwich mount style. Compared to sandwich mount, there is no top frame (the plate sits at the top), and it is screwed into the case's mounting posts from above.

The PCB (lard84.kicad_pro) is an 84-key design based on the RP2350 Stamp, made using KiCad 8.0. It is entirely hand-solderable (smallest footprint is 0603).

Lard84, from the project README — From the project README

Main components on the Lard84

RP2350_Stamp

Lard84 bill of materials (BOM)

88 components, 5 distinct parts.

Qty	Part	Footprint	Refs
1	RP2350_Stamp	RP2xxx_Stamp_SMD	U1
1	USB_B_Micro	CONN5_2013499-1_TEC	J3
84	D	D_SOD-123	D1, D2, D3, D4, D5, D6, D7, D8 +76
1	LED	LED_0603_1608Metric_Pad1.05x0.95mm_HandSolder	D85
1	150	R_0603_1608Metric_Pad0.98x0.95mm_HandSolder	R1

Lard84 design files

The KiCad project lives in the beulard/lard84 repository on GitHub; these links point at the commit this page was built from.

Layoutlard84.kicad_pcb
Schematiclard84.kicad_sch

Lard84: common questions

What microcontroller does the Lard84 use?

The Lard84 is built around the RP2350_Stamp, from the RP2040/RP2350 family.

How big is the Lard84 PCB?

The Lard84 measures 308.8 × 118.3 mm, has 2 copper layers and is 1.2 mm thick.

How many components are on the Lard84?

88 components, from 5 distinct parts. The full bill of materials is listed on this page.

Where can I download the Lard84 design files?

From the beulard/lard84 repository on GitHub, which has the KiCad layout and the schematic; the links under Design files point to each one.

Can I use the Lard84 design in my own project?

Yes, under the terms of its CC0-1.0 license, which beulard chose for the repository.

Can I test firmware for the Lard84 without the hardware?

Yes. HardLabs builds a simulation of the board from its netlist and BOM, so you can run and debug RP2040/RP2350 firmware against it before you order a PCB.