2 layers166 × 70 mm
Prototype
SteveCooling/MidiKeys
Will be a complete board with decoders for multiplexed sampling of analog sources and up to 61-key keybeds
75 parts8MIT
4 layers360 × 200 mm
Rgb switcher
michaelobed/rgb-switcher3An open-source switcher for analogue RGBS video, so you don't have to.
- Size
- 360 × 200 mm
- Copper layers
- 4
- Thickness
- 1.6 mm
- Parts
- 133
- Nets
- 241
- Pads
- 884
- Tracks, vias
- 1,871, 290
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 24 Jan 2025
- Updated
- 31 May 2026
Overview
Rgb switcher is an open-source printed circuit board by michaelobed, from the michaelobed/rgb-switcher repository on GitHub, published under the MIT licence. It is a 4-layer board of 360 × 200 mm with 133 parts on 241 nets, routed with 1,871 tracks and 290 vias.
It is built around the ATMEGA328PB-AU, SN74CBT3244CPW and 74HC238D, with the 74HC04D, 74HC138 and L7805 among its other parts. Its parts include 32 transistors, 22 connectors, 20 capacitors, 20 switches and 16 ICs. It belongs with the lEDs and displays and audio and music boards and the AVR (ATmega, ATtiny) boards of this library.
Main components
7
ATMEGA328PB-AU
TQFP-32(7x7)-40℃~+85℃ 1.8V~5.5V 10bit 1KB 20MHz 27 2KB 32KB 8 Bit AVR Built-in FLASH Power-on reset (POR)、Undervoltage detection (BOR/LVD/LVR/LVI)、Watchdog reset、External pin reset (NRST)、Built-in general-purpose timer、Programmable watchdog、Touch function TQFP-32(7x7) Microcontrollers (MCU/MPU/SOC) ROHSMicrochip TechnologyMicrocontrollers (MCU/MPU/SOC)
SN74CBT3244CPW
TSSOP-20-40℃~+85℃ 14pF 150ps 3Ω 4.8ns 4V~5.5V 5.7ns 8 TSSOP-20 Analog Switches, Multiplexers ROHSTexas InstrumentsSignal Switches, Multiplexers, Decoders
74HC238D
SOP-16SOP-16 Signal Switches, Multiplexers, Decoders ROHSMDDSignal Switches, Multiplexers, Decoders
74HC04D
SOP-14-40℃~+125℃ 1 1.5V~4.2V 1.9V、3.7V、5.2V 100mV、400mV、400mV 14ns@6V,50pF 2V~6V 2uA 5.2mA 5.2mA 500mV~1.8V 6 74HC SOIC-14 Inverters ROHSNexperiaInverters74HC138
SOP-160℃~+70℃ 24ns@5.0V,16pF 2V~6V 3/8 5.2mA 5.2mA 5uA 74HC Decoder Reverse function Single Supply SOP-16 Signal Switches, Multiplexers, Decoders ROHSGRSignal Switches, Multiplexers, Decoders
L7805
TO-220ST0℃~+125℃@(Tj) 1 1.2A 20V 2V@(1A) 42uV 500uA 5V 73dB@(120Hz) Fixed Positive Short Circuit Protection TO-220ST Voltage Regulators - Linear, Low Drop Out (LDO) Regulators ROHSOSENVoltage Regulators - Linear, Low Drop Out (LDO) Regulators
IRF540N
TO-2201 N-channel 1.35nF 100V 130W 280pF 33A 35mΩ@10V 4V 52nC@10V 85pF N-Channel TO-220 MOSFETs ROHSOSENMOSFETs
README
hardware/main_board/README.mdrgb switcher main board
Here's the KiCad design file for the board. I've included all required libraries as a lot of the components I had to find or make from scratch. I've also included a bill of materials (BOM) for reference, made to be compatible with JLCPCB's particular format. Bear in mind that you don't absolutely have to use the parts referenced in there if they aren't in stock on LCSC, or if you can source them from elsewhere, or if better/cheaper alternatives will work.
FWIW, here are some alternative links to things you will need. I used AliExpress myself, but these should be equivalent:
- Output indicator LEDs (Farnell)
- RGB LED connectors (Farnell)
- +5v out connector (Farnell)
- Input/output connectors (DigiKey)
- On/off switch (DigiKey)
changelog
v0.1
- initial version. mistakes were made. 🥲
v0.2
- corrected reversed pinout of icsp connector.
- corrected reversed pinout of uart connector.
- corrected orientation of prev/next buttons.
- corrected "output on" leds so rgb is red and ypbpr is green.
- corrected stupid pin numbering of mini-din footprint.
- added holes to 9-pin mini-din footprint to prevent ripping connector off board during disconnection.
- moved rgb/ypbpr switches closer to edge for ease of use.
- reduced brightness of "output on" leds.
- permitted switching between pins 4 and 5 of the input/output connectors to support using non-rgbs cables.
- connected PIN_SELEN net to front LED line decoders to allow them to be switched off.
Parts
133| Qty | Value | Footprint | References |
|---|---|---|---|
| 32 | IRF540N | Package_TO_SOT_SMD:TO-263-2 | Q1, Q2, Q10, Q11, Q12, Q13, Q14, Q15, Q16, Q17, Q18, Q19, Q20, Q21, Q22, Q23 +16 |
| 18 | 100n | Capacitor_SMD:C_0603_1608Metric | C1, C2, C4, C5, C7, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20 +2 |
| 9 | SN74CBT3244CPW | Package_SO:SOIC-20W_7.5x12.8mm_P1.27mm | U3, U4, U7, U8, U9, U10, U11, U12, U13 |
| 9 | csync/rgbs | JS102011JCQN:SW_JS102011JCQN | SW12, SW13, SW14, SW15, SW16, SW17, SW18, SW19, SW20 |
| 8 | 1k | Resistor_SMD:R_0603_1608Metric | R5, R6, R7, R8, R9, R10, R11, R12 |
| 8 | rgb/ypbpr | Button_Switch_SMD:SW_SPDT_PCM12 | SW1, SW2, SW3, SW4, SW5, SW6, SW7, SW8 |
| 4 | ground | MountingHole:MountingHole_4.3mm_M4_ISO14580_Pad | H1, H2, H3, H4 |
| 3 | 74HC238 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | U14, U15, U16 |
| 1 | +12v 3a in | Connector_BarrelJack:BarrelJack_CLIFF_FC681465S_SMT_Horizontal | J2 |
| 1 | +5v out | Connector_Phoenix_MC:PhoenixContact_MC_1,5_2-G-3.5_1x02_P3.50mm_Horizontal | J14 |
| 1 | 100u | Capacitor_SMD:CP_Elec_6.3x7.7 | C6 |
| 1 | 10k | Resistor_SMD:R_0603_1608Metric | R1 |
| 1 | 10u | Capacitor_SMD:C_0603_1608Metric | C3 |
| 1 | 6k8 | Resistor_SMD:R_0603_1608Metric | R3 |
| 1 | 74HC04 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | U6 |
| 1 | 74HC138 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | U5 |
| 1 | ATmega328PB-A | Package_QFP:TQFP-32_7x7mm_P0.8mm | U1 |
| 1 | L7805 | Package_TO_SOT_SMD:TO-263-2 | U2 |
| 1 | icsp | Connector_PinHeader_2.54mm:PinHeader_2x03_P2.54mm_Vertical | J5 |
| 1 | input 0 | KMDGX-9S-N:KMDGX9SN | J3 |
| 1 | input 1 | KMDGX-9S-N:KMDGX9SN | J4 |
| 1 | input 2 | KMDGX-9S-N:KMDGX9SN | J7 |
| 1 | input 3 | KMDGX-9S-N:KMDGX9SN | J8 |
| 1 | input 4 | KMDGX-9S-N:KMDGX9SN | J11 |
| 1 | input 5 | KMDGX-9S-N:KMDGX9SN | J12 |
| 1 | input 6 | KMDGX-9S-N:KMDGX9SN | J16 |
| 1 | input 7 | KMDGX-9S-N:KMDGX9SN | J17 |
| 1 | next | GT-TC050B:GT-TC060B | SW11 |
| 1 | on/off | MTS-102:SW_Toggle_Blue_wSlots | SW9 |
| 1 | output 0 on | LED_THT:LED_D5.0mm | D2 |
| 1 | output 1 on | LED_THT:LED_D5.0mm | D3 |
| 1 | output 2 on | LED_THT:LED_D5.0mm | D4 |
| 1 | output 3 on | LED_THT:LED_D5.0mm | D5 |
| 1 | output 4 on | LED_THT:LED_D5.0mm | D6 |
| 1 | output 5 on | LED_THT:LED_D5.0mm | D7 |
| 1 | output 6 on | LED_THT:LED_D5.0mm | D8 |
| 1 | output 7 on | LED_THT:LED_D5.0mm | D9 |
| 1 | power | LED_SMD:LED_0603_1608Metric | D1 |
| 1 | prev | GT-TC050B:GT-TC060B | SW10 |
| 1 | rgb 0 | Connector_Phoenix_MC:PhoenixContact_MC_1,5_4-G-3.5_1x04_P3.50mm_Horizontal | J1 |
| 1 | rgb 1 | Connector_Phoenix_MC:PhoenixContact_MC_1,5_4-G-3.5_1x04_P3.50mm_Horizontal | J6 |
| 1 | rgb 2 | Connector_Phoenix_MC:PhoenixContact_MC_1,5_4-G-3.5_1x04_P3.50mm_Horizontal | J9 |
| 1 | rgb 3 | Connector_Phoenix_MC:PhoenixContact_MC_1,5_4-G-3.5_1x04_P3.50mm_Horizontal | J13 |
| 1 | rgb 4 | Connector_Phoenix_MC:PhoenixContact_MC_1,5_4-G-3.5_1x04_P3.50mm_Horizontal | J15 |
| 1 | rgb 5 | Connector_Phoenix_MC:PhoenixContact_MC_1,5_4-G-3.5_1x04_P3.50mm_Horizontal | J18 |
| 1 | rgb 6 | Connector_Phoenix_MC:PhoenixContact_MC_1,5_4-G-3.5_1x04_P3.50mm_Horizontal | J21 |
| 1 | rgb 7 | Connector_Phoenix_MC:PhoenixContact_MC_1,5_4-G-3.5_1x04_P3.50mm_Horizontal | J22 |
| 1 | rgb output | KMDGX-9S-N:KMDGX9SN | J19 |
| 1 | uart | PJ-320B:BOOMELE_PJ-320B | J10 |
| 1 | ypbpr output | KMDGX-9S-N:KMDGX9SN | J20 |
Questions
How big is the Rgb switcher PCB?
It measures 360 × 200 mm and has 4 copper layers, 1.6 mm thick.
What parts does the Rgb switcher use?
133 parts, built around the ATMEGA328PB-AU, SN74CBT3244CPW, 74HC238D and 74HC04D. 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 Rgb switcher KiCad files?
From the michaelobed/rgb-switcher repository on GitHub, at the commit this page was made from: the board is hardware/main_board/main_board.kicad_pcb and its schematic hardware/main_board/connectors.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Rgb switcher design in my own project?
Its repository publishes it under the MIT licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
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