DingoPDM

DingoPDM is an Infineon Profet based Power Distribution Module.

Goals

• Learn more about PDMs and high DC current devices
• Learn about developing firmware for a more complex STM32 based project
• Create a low cost device that my friends and I can use in our project cars
• Layout the board to fit simple case designs
  • 3D printed top shell and flat aluminum heatsinks (no machining)
• Use low cost 1oz/0.5oz 4 layer PCBs
• Share my work with others for reference, inspiration or collaboration.

If this project does help you in any way, I'd appreciate a message!

Disclaimer

This is a personal hobby project. I am not a professional. Use at your own risk.

Hardware

• 4x Profet BTS7002-1EPP
  • 4x 14A outputs
  • With flyback diodes
• 4x Profet BTS7008-2EPA
  • 8x 8A outputs
• Profets connected using I2C GPIOs and ADCs
• 8x Digital Inputs
  • Ground switching
  • I2C GPIO
• STM32F303CCT6 Microcontroller
• 256Kbit FRAM
  • Settings storage
• 32MBit Flash
  • Logging or other purposes
• CAN transceiver
  • Terminating resistor selectable by GPIO output
• Board temperature measured between connectors
• 16x LEDs for output and device status
  • 3x additional LEDs for power and temperature status
• Onboard 12V to 5V to 3.3V regulation
  • 3.3V protected by Infineon ISP752R
• Super capacitor for real time clock
  • 32.768KHz clock included on STM32 for RTC
• M6 lug 12V power connection
• USB-C for:
  • Serial communication
  • Firmware update (DFU)
    • Boot select switch included
• Opto-isolated sleep/wakeup
  • For power shutdown (keyswitch)
  • Ground switched
  • Slider switch included for always on
• 12V voltage measurement
• THT test pads for easy connection of logic analyzer (ex: Saleae leads)
• AMPSeal 14 pin connectors
  • Gold contacts (14A each)

Connections

Connector	Pin	Function
A	1	Output 5
A	2	Output 4
A	3	Output 3
A	4	Output 2
A	5	Output 1
A	6	Output 6
A	7	Ground
A	8	Output 2
A	9	Output 9
A	10	Input 1
A	11	Input 2
A	12	Input 3
A	13	Input 4
A	14	On Switch
B	1	Output 7
B	2	Output 8
B	3	Output 9
B	4	Output 10
B	5	Output 11
B	6	Output 7
B	7	Output 8
B	8	Input 5
B	9	Output 12
B	10	Input 8
B	11	Input 7
B	12	Input 6
B	13	CAN H
B	14	CAN L

Open Items

• Design a new case and heatsink for the V4 board (AMPSeal connectors)

Issues

• The super cap drains faster than my calculations

Untested

• Thermal performance at high total loads
• AMPSeal connectors (V3 = DTM, V4 = AMPSeal)
• Opto-isolator on the SYS_WKUP2 pin
• SPI Flash (haven't used it yet)

Design Notes

• V3 of the board used DTM connectors, the switch to AMPSeal was made to:
  • Get away from the complicated clip design of the DTM PCB connector
    • This made it difficult to 3D print cases as the clips require accurate and strong features
  • Increase the terminal current rating (AMPSeal gold pins are rated much higher)
  • Get away from the TE DTM case which was fully sealed. That didn't allow for a heatsink to be added that would be externally exposed.
• The heatsink is designed to be 2 pieces. A spacer/spreader plate and a main plate
  • The spacer plate provides clearance for the THT pins of the AMPSeal connectors and the RedCube terminal while getting as close to the Profets as possible
  • Note: the spacer plate should be covered on both sides with a thermal pad material to electricaly isolate the heatsink while still providing a thermal interface (I use 3M 5583S)
  • The main plate holds the case and also sandwiches the spacer plate to the PCB
  • Here's an example of the V3 case:
  • 
  • 
• The LEDs are too close together which makes using light tubes in the case difficult
• A design could be decently waterproofed with some 3D printed TPU seals, but this is something I have not tried as my installation locations are on the interior

Photos

Some various photos of different versions