OpenPDM

Power Distribution Module

for Car / Motorcycle

Features:

  • DC 12V
  • 4 power channels with 5 modes of operation
  • 10 Amp per channel
  • 35 Amp total

Why yet another PDM?

Because it's:

  • Open: This documentation describes Open Hardware and is licensed under the CERN OHL v. 1.2. You may redistribute and modify this documentation under the terms of the CERN OHL v.1.2.
  • Simple: you can easy DIY. There are no programmed MCUs, rare elements, etc. Just wield, plug and play.
  • Universal: you can select any of 5 modes for each power channel independently.
  • Modular: it is not necessary for soldering all elements, if you do not want to use all modes for all channels. You can even cut the board, if less channels are used.

Schematic diargam

Schematic diagram (click for larger view)

Download Autodesk Eagle scheme and board files at the bottom of this page.

Modes of operation

There are 5 modes can be configured for each power channel. You can solder only necessary componencts for each mode of each chanel. Let's look again at the schematic diagram part:

  • Direct battery connection. Fuse in F1, JP1 and JP2 in any position. The output will be always powered from the battery. Only F1 fuse holder is needed.

All of the rest modes work only with "Accessory" line high. Connect it to suitable wire, which is switched by the Ignition switch.

  • Powered ON/OFF with Ignition switch. Fuse in F2, JP1: any, JP2: 1+2. You need F2 fuse holder, K1 relay, D1 diode and JP2 jumper header.
  • Powered ON/OFF with toggle switch. Fuse in F2, JP1: 2+3, JP2: 2+3. The output will be powered while the toggle switch is low (-12V). Connect toggle swich to IN1 input. You can also connect switch to IN1A, and do not solder JP1. Same components as above necessary plus JP1 jumper header.
  • Powered ON/OFF with electronically toggled push button. Fuse in F2, JP1: 1+2, JP2: 2+3. Push the button for power ON, push again for power OFF. Switching the "Accessory" off resets the toggle logic. Therefore the output always stays OFF when you turn ON ignition. The push button is on IN1 input, and must be "active low" - connects to -12V for action. All components needed.
  • Powered ON/OFF with additional switch or push button. Fuse in F2, JP1: any, JP2: 2+3. This mode is usefull for "passing lights" button. Connect "active low" button or switch to IN1A input and use it for power on the output regardless of main (IN1 connected) switch state.

One channel part (click for larger view)

PCB

The PCB is 53mm x 70mm Double sided. You can order it in one of PCB prototyping companies. I've ordered my in JLCPCB.com. They relatively cheap, and good quality. But you've to wait for shipping from China. Also they linked with LCSC.com, who are electronic components selling company. So you can combine orders to get PCB and components in one package.

At the bottom of this page you can find the Autodesk Eagle .BRD file and the .ZIP file (ready for PCB ordering).

PCB preview (click for full size)

Components:

  • F1-F8 MCCQ-122, Mini ATM Fuse Holder 15A 250V. I've got my here (Aliexpress link) Choose "Mini" type
  • IC1: 78L05F, SOT89, 5V VOLTAGE REGULATOR. Ordered here (LCSC link).
  • K1-K4: JJM1-12V, JJM1C, HALF-SIZE AUTOMOTIVE RELAY. Ordered here (LCSC link).
  • Q1-Q4: IRLML2030, SOT-23-3 N-Channel MOSFET N-CH 30V 5A. Ordered here (LCSC link).
  • U1-U4: MAX16054, SOT23-6 MAXIM Integrated power controller chip. Ordered here (LCSC link).
  • D1-D4: BAS321, SOD323-R DIODE. Ordered here (LCSC link).
  • JP1-JP8: 1x3 PIN HEADER. Look at the nearest radio/electronic hobby store.
  • C2: 0.33u, C0805K CAPACITOR. Look at the nearest radio/electronic hobby store.
  • C3: 0.1u, C0805K CAPACITOR. Look at the nearest radio/electronic hobby store.
  • C4: 33u, SMC_B POLARIZED CAPACITOR. Look at the nearest radio/electronic hobby store.
  • R1,R3,R5,R7: 12 kOhm, R0603 RESISTOR. Look at the nearest radio/electronic hobby store.
  • R2,R4,R6,R8: 100 Ohm, R0603 RESISTOR. Look at the nearest radio/electronic hobby store.
  • Wires: Use at least 16AWG wire for battery +12V and Ground connections. You can use thicker wire, just split core into additional wirepads. Use 18AWG for Power and Ground outputs. Use any wire gauge for the rest wires, but I whould suggest 20AWG at least for mechanical reliabless.
  • Connectors: Use something like an Anderson Powerpole 45 Amp connectors for battery +12V and Ground connections. I've get here (Aliexpress link). Anything of you choise for the other connections. I'd suggest 3.9mm bullet connectors, as widely used in the motorcycles.

Casing

You can design and print any casing you want on 3D printer. Or you can download my model from Thingiverse.com and order it on any 3D-printing service.

Use electronic potting compound for adding some weather and vibration proofness to your work.

NOTE!!! DO NOT use plumbing silicone sealeants, as most of them are vinegar based, and will kill your device.

3D printed casing (click for full size)

Assembly Top view (click for full size)

Weatherproofing the device (click for full size)

Assembly Bottom view (click for full size)

Electronic potting compound (click for full size)

Donate

You can build, modify and distribute this device freely while keeping the CERN OHL v.1.2 compliance.

But if you like my work you can send me some donate in gratitude.

Contact me

Contact me: openpdm@xren.me