Next μ

Next μ or Next Micro is a Pro Micro/Elite-C compatible ATmega32U4 board, specialized design for keyboards.

It has mid-mount USB Type-C and more available pins (25 pins, all pins of ATmega32U4 except PE2/HWB) than both Pro Micro (18 pins) and Elite-C (24 pins).
The on-board RESET button makes development easier.

A part of ErgoSNM keyboard project.

Preview

Front	Back	Layers

Pinouts

Func	32U4	L <-> R	32U4	Func
	PB7*		PB0
TX	PD3		RAW
RX	PD2		GND
	GND		RESET
	GND		VCC
SDA	PD1		PF4	A3
SCL	PD0*		PF5	A2
A6	PD4		PF6	A1
	PC6*		PF7	A0
A7	PD7*		PB1	SCLK
	PE6		PB3	MISO
A8	PB4		PB2	MOSI
A9	PB5*		PB6*	A10

Bottom row from left to right: PD6, PD5, PC7*, PF1, PF0.

• The pin marked with * can output PWM.
• RAW: LDO Vin pin.

The pinouts not fully compatible with Elite-C.

Jumper Config

• JP1: LDO bypass.
  • Open: VCC is 3.3V (LDO Vout).
  • Closed: VCC is 5V (VBUS or RAW).

BOM

Designator	Value	Footprint
C1,C2	20pF	0402 (1005 Metric)
C3,C6,C7	100nF	0402 (1005 Metric)
C4,C5,C8,C9	1uF	0402 (1005 Metric)
D1	B5817	SOD-323
F1	500mA, 6V	0805 (2012 Metric)
J1	USB_C_Receptacle_USB2.0	918-418K2024S40000
R1,R2	5.1k	0402 (1005 Metric)
R3,R4	22	0402 (1005 Metric)
R5	10k	0402 (1005 Metric)
SW1	RESET	B3U-1000P
U1	ATmega32U4-M	QFN-44-1EP 7x7mm P0.5mm EP5.2x5.2mm
U2	RT9013-33GB	SOT-23-5
Y1	8MHz	2Pin 5x3.2mm

See also doc/next-micro_bom.csv.

There is not designator silkscreen on PCB, please use your browser to open the ibom.html file (placed in release page and doc/) to refer to the placement of the parts, it is generated by Interactive HTML BOM plugin.

PCBA

The BOM and CPL files for PCBA are placed in the doc/ folder and release page.

Board Characteristics

• Copper layer count: 2
• Board thickness: 1.6 mm
• Board overall dimensions: 17.78 x 33.02 mm (0.7 x 1.3 inch)
• Min track/spacing: 0.13 mm / 0.13 mm
• Min hole diameter: 0.3 mm
• Castellated pads: No
• Edge card connectors: No
• Plated board edge: No

Disclaimer

These files without warranty of any kind, use at your own risk, it is recommended to check yourself before manufacture.

For the full statement, please see LICENSE.