PSU and PDU board redesign - MKII

  • Posted:
  • Proposals: 1
  • Remote
  • #2583126
  • Awarded
Blagoja S.
has already sent a proposal.
  • 0

Description

Experience Level: Intermediate
Hi Blagoja, I would like to redesign some parts of the power supply boards.

PDU (keep same footprint) 
0 - Cover the exposed areas with mask. We shouldn't have so much copper as it presents a shorting risk.

1 - need to replace the Teensy 3.2 with a Teensy 3.5.

2 - move the teensy form PSU to PDU. This also powers the other ICs on PDU. 

3- remove the I2C connector that goes to PSU. Not needed since we do all the work on PDU.

4- add current (Analog ACS724KMA) and voltage (SPI ADC: TLV2556) sensing on PDU. One current IC per battery and one ADC per board. This ADC has 11 inputs so it's fine to do the work.

5 - add a I2C mux (TCA9548A) on PDU that connects to each battery BMS (they have the same address) - this mux IC allows one connection to teensy and direct connection to each battery BMS, preventing address clash.  

6 - sample the NTC (10k NTC) from each battery and feed to the ADC. You need to design the circuit for NTC and route it to the ADC.
https://www.feyelektronik.de/en/downloads/db-pa-l1710.pdf

7 - expand the charging connector to 10 pairs (20 pins) - the current one is 5 pairs (10 pins)

8 - add 2x2700uF on input of each battery so we have a buffer capacitance (smd preferred)
https://uk.farnell.com/rubycon/35trv2200m16x21-5/cap-2200-f-35v-smd/dp/2535798RL
In total we should have 6 capacitors. If the space is a problem we can use only one capacitor per battery. 

9 - SPI and I2C from ADC + MUX should be made avaiable on a JST XAD connector. In case we want to take this to another IC later on. We might end up removing the Teensy in a future iteration and using a central processor. So I need to be able to run a cable there. 
10 - change the 40 pin connector to a 30 pin XAD.

11- add linear regulator: TL720M05 - TO252 package. Use jumper to select if we use this or USB power. 

PSU:
0 - Cover the exposed areas with mask. We shouldn't have so much copper as it presents a shorting risk

1 - Remove teensy as mentioned above.

2 - Add 10 x JST XAD 2 pin connectors for fan power. They are 12 volts connectors.

3 - make board smaller: 60 x 100 mm should be OK considering how many components we remove.



Let me know what you think.
Andrei

New Proposal

Create an account now and send a proposal now to get this project.

Sign up

Clarification Board Ask a Question

    There are no clarification messages.