GRAM MINI

gabboak·GRAM_MINI·KICAD GRAM_MINI_ALPHA/GRAM_MINI_BOTTOM_HOME_ROW.kicad_pcb

About the GRAM MINI PCB

GRAM MINI is an open source RP2040/RP2350 PCB design by gabboak, published on GitHub under the GPL-3.0 license. It is a 2-layer board measuring 226 × 130 mm, with 60 components from 23 distinct parts.

Its main chip is the RP2040, from the RP2040/RP2350 family. Other key parts include the XC6206, USBLC6-2SC6 and W25Q128JVS. By type, the board carries 17 capacitors, 11 resistors, 4 ICs, 3 diodes, 2 connectors and 1 crystal.

From the project

*ALPHA VERSION, NOT MEANT FOR PRODUCTION YET.

GRAM Mini is a fork of the GRAM Slim, a low profile 21-button controller designed for Smash and FGC games. The GRAM MINI retains the same 21-button layout and firmware compatibility as the GRAM Slim, while downsizing the PCB and case design around a smaller, more compact form factor. This project is fully open-source and is intended to be very easy and staight-foward to build .

Main components on the GRAM MINI

XC6206 USBLC6-2SC6 RP2040 W25Q128JVS

GRAM MINI bill of materials (BOM)

60 components, 23 distinct parts — part numbers from the project's BOM.

Qty	Part	Footprint	Refs
1	XC6206	SOT-23	U1
1	USBLC6-2SC6	SOT-23-6	U2
1	RP2040	RP2040-QFN-56	U3
1	W25Q128JVS	SOIC-8_5.23x5.23mm_P1.27mm	U4
1	12MHZ 12MHz	Crystal_SMD_3225-4Pin_3.2x2.5mm	Y1
1	C456013 USB C Connector	TYPE-C_24P_QCHT	J1
1	JTAG_TC2030	CON_TC2030_outlined	J2
21	choc_SW_HS	Kailh_socket_PG1350	CH1, CH2, CH3, CH4, CH5, CH6, CH7, CH8 +13
1	C70076 500 mA	Fuse_1206_3216Metric	F1
2	C8598 Schottky Diode	D_SOD-123	D1, D2
1	C84256 GREEN	LED_0805_2012Metric	D3
4	1UF 1uF	C_0402_1005Metric	C1, C2, C4, C10
10	100NF 100nF	C_0402_1005Metric	C3, C5, C6, C11, C12, C13, C14, C15 +2
2	22PF 22pF	C_0402_1005Metric	C7, C8
1	10UF 10uF	C_0402_1005Metric	C9
1	1M	R_0603_1608Metric	R1
2	5.1K 5.1k	R_0402_1005Metric	R2, R3
1	470	R_0402_1005Metric	R4
1	5.6K 5.6k	R_0603_1608Metric	R5
1	10K 10k	R_0603_1608Metric	R6

Show 3 more

Qty	Part	Footprint	Refs
1	10K 10k	R_0402_1005Metric	R7
2	27	R_0603_1608Metric	R8, R9
2	1k	R_0402_1005Metric	R10, R11

GRAM MINI design files

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

GRAM MINI: common questions

What microcontroller does the GRAM MINI use?

The GRAM MINI is built around the RP2040, from the RP2040/RP2350 family.

How big is the GRAM MINI PCB?

The GRAM MINI measures 226 × 130 mm, has 2 copper layers and is 1.6 mm thick.

How many components are on the GRAM MINI?

60 components, from 23 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.

Where can I download the GRAM MINI design files?

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

Can I use the GRAM MINI design in my own project?

Yes, under the terms of its GPL-3.0 license, which gabboak chose for the repository.

Can I test firmware for the GRAM MINI 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.