2 layers139.2 × 95.6 mm
IGBT DRIVER
EmadBahra/open-source-IGBT-gate-driver
This is a beta version and it's not tested yet, so use it at your own risk under GPL v3
240 parts5
2 layers59.2 × 48.8 mm
An Amiga Serial Midi Interface in open hardware
- Size
- 59.2 × 48.8 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 28
- Nets
- 55
- Pads
- 111
- Tracks, vias
- 114, 0
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 6 (file 20211014)
- Created
- 5 Apr 2023
- Updated
- 11 Jun 2025
Overview
MIDI is an open-source printed circuit board by retronicdesign, from the retronicdesign/AmigaMidi repository on GitHub. It is a 2-layer board of 59.2 × 48.8 mm with 28 parts on 55 nets, routed with 114 tracks and 0 vias.
It is built around the MAX232N, 6N136S and 1N4148WT. Its parts include 8 resistors, 7 capacitors, 4 connectors, 3 ICs and 3 diodes. It belongs with the audio and music and interfaces and adapters boards of this library.
Main components
3
MAX232N
PDIP-160℃~+70℃ 120Kbps 2 2 4.5V~5.5V Transceiver PDIP-16 RS232 ICs ROHSTexas InstrumentsRS232 ICs
6N136S
SMD-8P-40℃~+100℃ 1 1.45V 19% 1Mbit/s 1kV/us 20V 20mA 25mA 4.5V~18V 5V 5kV 800ns 800ns 8mA DC SMD-8P Logic Output Optoisolators ROHSAOTELogic Output Optoisolators
1N4148WT
SOD-523-55℃~+150℃ 1.25V@150mA 100V 150mA 150mW 1uA@75V 2A 4ns Independent SOD-523 Switching Diodes ROHShongjiachengSwitching Diodes
README
README.mdAmiga Serial Midi Adapter V1.3
Schematic
(C)2025 Retronic Design - Open Hardware
Features
- This serial midi interface is compatible with most Amiga Midi softwares.
- It simply convert serial RS-232 RX and TX signals to MIDI TTL standard.
- MIDI IN is opto-isolated to prevent ground loops and induction noise.
- Self powered via serial port.
- Convenient thru connector to connect other instruments to MIDI IN in daisy-chain.
- Tested on Bar and Pipes professional and OCTA-MED. (Let us know yours!)
Versions
- v1.0 Initial release
- v1.1 Corrected LED polarity
- v1.2 Corrected DB-25 PCB footprint
- v1.3 Corrected Schematic and PCB (Larger traces / LED alignement / Smaller but capable 5v regulator)
PCB
Pictures
*Please note that this picture is an outdated version 1.0 of the serial Midi adapter.
You can have it build at PCBWay under my shared projects.
Part List
| Quantity | Designator | Part |
|---|---|---|
| 1 | C1 | 100pF |
| 6 | C2,C3,C4,C5,C6,C7 | 0.1uF |
| 1 | D1 | 1N4148 |
| 2 | D2,D3 | LED |
| 3 | J1,J2,J3 | DIN 5 FEMALE |
| 1 | J4 | D-SUB 25 Female |
| 5 | R1,R2,R3,R4,R5 | 220 Ohms |
| 2 | R6,R8 | 1K |
| 1 | R7 | 3.3K |
| 1 | U1 | 6N136 |
| 1 | U2 | MAX232 |
| 1 | U3 | L4931-5.0 |
Parts
28| Qty | Value | Footprint | References |
|---|---|---|---|
| 7 | 0.1uF | Capacitor_THT:C_Disc_D3.0mm_W1.6mm_P2.50mm | C1, C2, C3, C4, C5, C6, C7 |
| 5 | 220 | Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal | R1, R2, R3, R4, R5 |
| 2 | 1K | Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal | R6, R8 |
| 2 | LED | LED_THT:LED_D3.0mm | D2, D3 |
| 1 | 1N4148WT | Diode_THT:D_A-405_P7.62mm_Horizontal | D1 |
| 1 | 3.3K | Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal | R7 |
| 1 | 6N136S | Package_DIP:DIP-8_W7.62mm_Socket | U1 |
| 1 | DB25_Female | Connector_Dsub:DSUB-25_Female_Horizontal_P2.77x2.84mm_EdgePinOffset7.70mm_Housed_MountingHolesOffset9.12mm | J4 |
| 1 | L4931-5.0 | Package_TO_SOT_THT:TO-92L_Inline | U3 |
| 1 | LOGO | Symbol:MIDI | G*** |
| 1 | LOGO | Symbol:RetronicDesign | G*** |
| 1 | MAX232 | Package_DIP:DIP-16_W7.62mm | U2 |
| 1 | MIDI IN | Downloads:MIDI_DIN5 | J1 |
| 1 | MIDI OUT | Downloads:MIDI_DIN5 | J2 |
| 1 | MIDI THRU | Downloads:MIDI_DIN5 | J3 |
The 27 most common of 28 parts.
Similar boards
- 4 layers172 × 140.5 mm
- 4 layers121.9 × 66 mm
- 2 layers40 × 55 mm
- 2 layers132.1 × 45.7 mm
IPoS
peterheinrich/InternetOverSpaghetti
Transmitting IP packages over a pair of spaghetti thus demonstrating how media independent IP really is.
42 parts342 - 2 layers60.5 × 31.5 mm
Ps2-serial mouse adapter
necroware/ps2-serial-mouse-adapter
PS/2 to serial port mouse adapter
13 parts89GPL-3.0 - 2 layers79.7 × 35.1 mm
USB-2-232
LimeProgramming/USB-serial-mouse-adapter
Convert USB mouse to Serial mouse using Pi Pico
29 parts50MPL-2.0 - 2 layers148.3 × 116.6 mm
KiCAD RetroArduInput
RetroFuturisticEngineer/RetroARDUInput
Use USB Keyboards, Mice and Joysticks on PC/XT, PC/AT, Tandy 1000, Atari, Amiga, C64 and Apple
48 parts25LGPL-2.1
Questions
How big is the MIDI PCB?
It measures 59.2 × 48.8 mm and has 2 copper layers, 1.6 mm thick.
What parts does the MIDI use?
28 parts, built around the MAX232N, 6N136S and 1N4148WT. 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 MIDI KiCad files?
From the retronicdesign/AmigaMidi repository on GitHub, at the commit this page was made from: the board is MIDI.kicad_pcb and its schematic MIDI.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the MIDI design in my own project?
Its repository states no licence, so its author keeps all rights: ask retronicdesign before reusing the design.