Small Multicell USB Type C Charger

USB Type C has up to 100W of charging capability, perfect for a multicell charger

Similar projects worth following
We will be utilizing a TI multicell charger and balancer chip along with shared package transistor pairs to produce a small USB charger design that could fit onboard a drone or other small systems.

The board is based on the Cypress CCG2 USB PD negotiator and the TI BQ40z60RHB.  The BQ40z60RHB includes both charger control logic and charge balancer capabilities for 2-4 cell batteries.  (It also can do single cell, though it is over kill.)  The CCG2 will allow up to 100W of power and the BQ40z60RHB through the on board charging transistors will utilize that for charging.

We will be using XT-30 connectors for battery and system connections and a JST-XH cell balancer connector.

The CCG2 will be in multi master master slave i2c mode to help monitor charging and run LED status indicators with or without a host microcontroller connection by i2c.

I plan to re-lay the board so that it will easily mount on drones or other electronics to provide charging.

The board needs some significant tweaks and firmware, but should be functional soon.

  • Well it has been ages, but...

    Chris Hamilton09/06/2019 at 20:38 1 comment

    I am putting a variation of the design up on github -

    It is a specific application that was requested awhile back.  I will be making a few variants including a powerbank, drone charger, and a brushless controller similar to this one.  The design is a bit larger, but it can be shrunk down to about the same size.  The original design would require 12-20V from the USB source.  Now it will be able to accept 5-20V for 1-4 cells in the design.  The design can obviously be reduced by a specified cell count and application.

  • Update on design

    Chris Hamilton10/22/2018 at 22:57 2 comments

    Hi, I have been reworking the design and plan to utilize the newer BQ40Z80.  I am also trying to fit in an optional BQ25710 (or 13 or 08) to provide boost when connected to legacy USB power sources.  At the moment I am fighting TI's shop as they don't want to sell me the EVM for the BQ25710 or provide samples.  I guess they no longer provide service to small engineering companies.

  • Connector changes

    Chris Hamilton04/25/2018 at 03:56 0 comments

    The JST XH, which is a battery pack standard, is just so huge.  I am pondering/researching any other solution.  I would love to move it as close as possible to the XT 30s, but it going to be a huge amount of board space. 

    The Tag-connect SWD is also a bit problematic.  In theory the CCG2 should always be programmable by the CC line, but I don't want to require a Cypress board to do firmware updates. 

    At the same time, I don't think the hobby world would be happy with such a pricey (but great) connector.  I am guessing that I'll switch to the cortex 1.27mm 10 pin, which is actually bigger.  The board really only needs 5 pins for SWD and there are some amazing 1.0mm spaced connectors out there....  But that wouldn't be any standard.

    I have a long flight coming up, so I'll try to make some decisions and make some progress.

  • Redesign

    Chris Hamilton03/15/2018 at 17:29 0 comments

    The original design layout wasn't well thought out.  I am currently working to put XT-30 board mount connectors on the top and bottom of the board on the same side edge.  They will be offset so that in between their connections the system FETs will fit.  The JST XH connector will be near them as well as a small SMBUS connector and the USB Type-C will be on the opposite side.

    I may experiment with swapping the XH connector to something smaller as it really is the biggest connector on the board.  There are many more compact connectors that can support balancing.

View all 4 project logs

Enjoy this project?



Chris Hamilton wrote 07/16/2018 at 20:54 point

Yeah, that is a good idea.  Thanks!

  Are you sure? yes | no

Shannon Wynter wrote 07/16/2018 at 08:13 point

Feedback resistor, maybe use a dipswitch to select?

  Are you sure? yes | no

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates