Auth75

Lumethra·Auth75·PCB/Auth75.kicad_pcb

About the Auth75 PCB

Auth75 is an open source RP2040/RP2350 PCB design by Lumethra, published on GitHub. It is a 2-layer board measuring 326.7 × 132.3 mm, with 208 components from 21 distinct parts.

Its main chip is the Raspberry Pi Pico 2W, from the RP2040/RP2350 family. Other key parts include the SL2.1s, DW01A, MCP73831T-2ACI/OT and PCA9536DGKR. By type, the board carries 81 diodes, 78 switches, 19 resistors, 14 capacitors, 5 ICs and 5 transistors.

It belongs with the keyboards, power & battery and sensors designs in this gallery.

From the project

This is a 75% keyboard with a fingerprint sensor. What? A fingerprint sensor in a keyboard? Yes, you've heard it right! This keyboard includes a working fingerprint sensor. But how does it work? Aren't fingerprint sensors tied to motherboards? Continue reading, to get an answer t

I always wanted a good keyboard with a working fingerprint sensor, because my password is always too long and I am used to the one on my laptop. Why not just use the one on my laptop? Because I want to close my laptop lid while using a monitor. The second reason is that the one on my laptop doesnt…

Auth75, from the project README — From the project README

Main components on the Auth75

Raspberry Pi Pico 2W SL2.1s DW01A MCP73831T-2ACI/OT PCA9536DGKR

Auth75 bill of materials (BOM)

208 components, 21 distinct parts — part numbers from the project's BOM.

Qty	Part	Footprint	Refs
1	Raspberry Pi Pico 2W RASPBERRY PI PICO 2W Raspberry Pi(树莓派)	COMM-SMD_L51.0-W21.0-P2.54_PICOW	U1
1	SL2.1s SL2.1S CoreChips(和芯润德)	SSOP-16_L4.6-W2.6-P0.53-LS4.0-BL	U2
1	DW01A DW01A_C351410 PUOLOP(迪浦)	SOT-23-6_L2.9-W1.6-P0.95-LS2.8-BL	U3
1	MCP73831T-2ACI/OT MICROCHIP(美国微芯)	SOT-23-5_L3.0-W1.7-P0.95-LS2.8-BL	U4
1	PCA9536DGKR TI(德州仪器)	VSSOP-8_L3.0-W3.0-P0.65-LS4.9-BL	U5
3	MMBT3904(RANGE:100-300) MMBT3904-C20526 CJ(江苏长电/长晶)	SOT-23-3_L2.9-W1.3-P1.90-LS2.4-BR	Q1, Q2, Q3
1	SS8550 Y2(RANGE:200-350) SS8550_C8542 CJ(江苏长电/长晶)	SOT-23-3_L2.9-W1.3-P1.90-LS2.4-BR	Q4
1	FS8205A FS8205A_C2830320 TECH PUBLIC(台舟)	SOT-23-6_L2.9-W1.6-P0.95-LS2.8-BR	Q5
1	S2B-PH-SM4-TB(LF)(SN) S2B-PH-SM4-TB JST	CONN-SMD_P2.00_S2B-PH-SM4-TB-LF-SN	CN1
1	046809610110846+ Kyocera AVX	CONN-SMD_10P-P0.50_046809610110846	FPC1
78	C2803348 ~	SW_Hotswap_Kailh_MX	S1, S2, S3, S4, S5, S6, S7, S8 +70
4	TYPE-C 16PIN 2MD(073) TYPE-C 16PIN 2MD SHOU HAN(首韩)	USB-C-SMD_TYPE-C-6PIN-2MD-073	USB1, USB2--RPI_Pico_W1, USB3, USB4
81	C81598 ~	D_SOD-123	D1, D2, D3, D4, D5, D6, D7, D8 +73
8	1UF 1uF	C_0603_1608Metric	C1, C2, C3, C5, C7, C10, C11, C12
4	100NF 100nF	C_0603_1608Metric	C4, C6, C8, C14
2	4.7UF 4.7uF	C_0603_1608Metric	C9, C13
4	5.1K 5.1k	R_0603_1608Metric	R1, R2, R12, R13
6	56K 56k	R_0603_1608Metric	R3, R4, R5, R6, R7, R8
6	1k	R_0603_1608Metric	R9, R10, R11, R14, R16, R19
1	100	R_0603_1608Metric	R15

Show 1 more

Qty	Part	Footprint	Refs
2	4.7K 4.7k	R_0603_1608Metric	R17, R18

Auth75 design files

The KiCad project lives in the Lumethra/Auth75 repository on GitHub; these links point at the commit this page was built from.

Auth75: common questions

What microcontroller does the Auth75 use?

The Auth75 is built around the Raspberry Pi Pico 2W, from the RP2040/RP2350 family.

How big is the Auth75 PCB?

The Auth75 measures 326.7 × 132.3 mm, has 2 copper layers and is 1.6 mm thick.

How many components are on the Auth75?

208 components, from 21 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 Auth75 design files?

From the Lumethra/Auth75 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 Auth75 design in my own project?

The repository has no license, so all rights stay with Lumethra. Use it as a reference, and ask the author before reusing the design.

Can I test firmware for the Auth75 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.