2 layers25.5 × 25 mm Microcharge2, the printed circuit board in 3D

Microcharge2

Small Li-Ion battery management development board with charging and protection, 3.3V output.

Size: 25.5 × 25 mm
Copper layers: 2
Thickness: 1.6 mm
Parts: 30
Nets: 13
Pads: 71
Tracks, vias: 17, 30
Pours: 4
Routed: Yes
KiCad: KiCad 9.0 (file 20241229)
Created: 14 Mar 2026
Updated: 14 Mar 2026

Overview

Microcharge2 is an open-source printed circuit board by 4f48, from the 4f48/microcharge repository on GitHub, published under the CERN-OHL-S-2.0 licence. It is a 2-layer board of 25.5 × 25 mm with 30 parts on 13 nets, routed with 17 tracks and 30 vias.

It is built around the AP2112K-3.3, DW03C and MCP73831T-2ACI/OT-HXY, with the USB4135-GF-A among its other parts. Its parts include 7 capacitors, 5 resistors, 3 ICs, 3 connectors and 2 diodes. It belongs with the power boards of this library.

Main components

Parts

Qty	Value	Footprint	References
4	MountingHole	MountingHole:MountingHole_2.2mm_M2_ISO7380	H1, H2, H3, H4
3	1u	Capacitor_SMD:C_0603_1608Metric_Pad1.08x0.95mm_HandSolder	C4, C5, C6
2	4.7u	Capacitor_SMD:C_0603_1608Metric_Pad1.08x0.95mm_HandSolder	C2, C3
2	5.1k	Resistor_SMD:R_0402_1005Metric_Pad0.72x0.64mm_HandSolder	R4, R5
2	Conn_01x02_MountingPin	Connector_Molex:Molex_CLIK-Mate_502382-0270_1x02-1MP_P1.25mm_Vertical	J2, J3
1	+3	TestPoint:TestPoint_Pad_D1.0mm	TP3
1	+B	TestPoint:TestPoint_Pad_D1.0mm	TP4
1	100	Resistor_SMD:R_0603_1608Metric_Pad0.98x0.95mm_HandSolder	R1
1	100n	Capacitor_SMD:C_0603_1608Metric_Pad1.08x0.95mm_HandSolder	C1
1	10u	Capacitor_SMD:C_0603_1608Metric_Pad1.08x0.95mm_HandSolder	C7
1	2k	Resistor_SMD:R_0603_1608Metric_Pad0.98x0.95mm_HandSolder	R2
1	470	Resistor_SMD:R_0603_1608Metric_Pad0.98x0.95mm_HandSolder	R3
1	AP2112K-3.3	Package_TO_SOT_SMD:SOT-23-5_HandSoldering	U1
1	DW03C	Package_TO_SOT_SMD:SOT-23-5_HandSoldering	U2
1	ESD5Zxx	Diode_SMD:D_SOD-523	D2
1	GND	TestPoint:TestPoint_Pad_D1.0mm	TP6
1	I	TestPoint:TestPoint_Pad_D1.0mm	TP1
1	LED	LED_SMD:LED_0603_1608Metric_Pad1.05x0.95mm_HandSolder	D1
1	MCP73831T-2ACI/OT	Package_TO_SOT_SMD:SOT-23-5_HandSoldering	U3
1	USB4135-GF-A	Connector_USB:USB_C_Receptacle_GCT_USB4135-GF-A_6P_TopMnt_Horizontal	J1
1	V-	TestPoint:TestPoint_Pad_D1.0mm	TP5
1	VB	TestPoint:TestPoint_Pad_D1.0mm	TP2

Questions

How big is the Microcharge2 PCB?

It measures 25.5 × 25 mm and has 2 copper layers, 1.6 mm thick.

What parts does the Microcharge2 use?

30 parts, built around the AP2112K-3.3, DW03C, MCP73831T-2ACI/OT-HXY and USB4135-GF-A. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.

Where can I download the Microcharge2 KiCad files?

From the 4f48/microcharge repository on GitHub, at the commit this page was made from: the board is microcharge2.kicad_pcb and its schematic microcharge2.kicad_sch. PCBKit opens the board in the browser, with nothing to install.

Can I use the Microcharge2 design in my own project?

Its repository publishes it under the CERN-OHL-S-2.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).

Category and platform

Power

Project files

Show this board on your page

A live frame, for any web page

<iframe src="https://pcbkit.io/embed/boards/4f48-microcharge" title="Microcharge2 in PCBKit" width="100%" height="480" style="border:0;border-radius:12px" allow="fullscreen" loading="lazy"></iframe>

A picture

<img src="https://pcbkit.io/embed/boards/4f48-microcharge.jpg" alt="Microcharge2" width="1200" height="900">

A picture that opens the board, for a README

[![Microcharge2](https://pcbkit.io/embed/boards/4f48-microcharge.jpg?size=s)](https://pcbkit.io/boards/4f48-microcharge)

Source

Repository: 4f48/microcharge
Board file: microcharge2.kicad_pcb
Commit: 1fb967a
Licence: CERN-OHL-S-2.0

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