Eimer

AndrewJ-25·Eimer·pcb/eimer/eimer.kicad_pcb

About the Eimer PCB

Eimer is an open source RP2040/RP2350 PCB design by AndrewJ-25, published on GitHub under the MIT license. It is a 2-layer board measuring 78 × 68 mm, with 66 components from 21 distinct parts.

Its main chip is the RP2040, from the RP2040/RP2350 family. Other key parts include the MCP1700x-330xxTT, TPS61221DCK, W25Q16JVUXIQ TR and LIS2DW12. By type, the board carries 20 capacitors, 18 resistors, 8 diodes, 5 ICs, 2 connectors and 2 battery holders.

It belongs with the dev boards & breakouts designs in this gallery.

From the project

Eimer is a compact devboard using RP2040 chip

A multi-axis accelerometer, 8 LEDs and 8 GPIO pads make Eimer an ideal wearable device. Solder pads are accompanied by holes to run the wire through, so there is no strain on the solder joint.

Eimer can be programmed using Arduino framework. Two mounting holes can be attached to a lanyard necklace, or safety pins.

Eimer can be powered with USB C or two CR2032 button cells (the board will work with one button cell, with a shorter battery life). Important note: do not plug in USB while cells are inserted!

Eimer, from the project README — From the project README

Main components on the Eimer

RP2040 MCP1700x-330xxTT TPS61221DCK W25Q16JVUXIQ TR LIS2DW12

Eimer bill of materials (BOM)

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

Qty	Part	Footprint	Refs
1	RP2040	QFN-56-1EP_7x7mm_P0.4mm_EP3.2x3.2mm	U1
1	MCP1700x-330xxTT	SOT-23	U2
1	TPS61221DCK	Texas_R-PDSO-G6	U3
1	W25Q16JVUXIQ TR	Winbond_USON-8-1EP_3x2mm_P0.5mm_EP0.2x1.6mm	U4
1	LIS2DW12	LIS2DS12	U5
1	12 MHz	Crystal_SMD_3225-4Pin_3.2x2.5mm	Y1
1	Conn_01x03	PinHeader_1x03_P2.54mm_Horizontal	J3
1	USB_C_Receptacle_USB2.0_14P	USB_C_Receptacle_HRO_TYPE-C-31-M-12	J4
9	TestPoint	TestPoint_THTPad_D1.5mm_Drill0.7mm	3.3V, GPIO11, GPIO12, GPIO13, GPIO15, GPIO18, GPIO19, GPIO20 +1
2	Battery_Cell	BatteryHolder_Multicomp_BC-2001_1x2032	BT1, BT2
8	LED	LED_0201_0603Metric	D1, D2, D3, D4, D5, D6, D7, D8
1	4.7uH	L_APV_ANR3015	L1
2	1uF	C_0402_1005Metric	C1, C10
12	0.1uF	C_0402_1005Metric	C2, C3, C4, C5, C6, C7, C8, C9 +4
4	10uF	C_0603_1608Metric	C13, C14, C19, C20
2	33pF	C_0402_1005Metric	C15, C16
2	5.1K	R_0402_1005Metric	R1, R2
2	27	R_0402_1005Metric	R3, R4
10	1k	R_0402_1005Metric	R5, R6, R10, R11, R12, R13, R14, R15 +2
2	10k	R_0402_1005Metric	R7, R18

Show 1 more

Qty	Part	Footprint	Refs
2	4.7k	R_0402_1005Metric	R8, R9

Eimer design files

The KiCad project lives in the AndrewJ-25/Eimer repository on GitHub; these links point at the commit this page was built from.

Eimer: common questions

What microcontroller does the Eimer use?

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

How big is the Eimer PCB?

The Eimer measures 78 × 68 mm, has 2 copper layers and is 1.6 mm thick.

How many components are on the Eimer?

66 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 Eimer design files?

From the AndrewJ-25/Eimer 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 Eimer design in my own project?

Yes, under the terms of its MIT license, which AndrewJ-25 chose for the repository.

Can I test firmware for the Eimer 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.