Frontend works!

A project log for Open BMS

3-8S Standalone BMS Desing. Open Source Software/Hardware

ben-brownBen Brown 07/25/2017 at 12:310 Comments

The PCB's arrived a few days ago, but it took me a day to find the one IC I had left from my two samples.

Building the board was a fairly normal deal, I used hot air to mount the ISL and MOSFET, and then just hand soldered the rest with the TS100 with the new C series tip.

Powering up the IC using a current limited supply looked good, and no shorts showed up testing with a multimeter (apart from the jumpers on the back, as I was setting this up for 3S, I had to short all the jumpers).

Once you connect a battery to the balance connector and the main power connector, you need to provide some voltage on the charging input to wake the unit up out of sleep mode.

The AFE powered up and allowed the battery voltage out the first time!

Using the testing code for the Arduino to talk to the unit, I programmed all the settings to suit my Lithium battery packs and the unit seems to be testing well.

After building up the AFE board I realised my layout mistake on the front panel board where I have used the wrong package for the MSP430. Derp.

I will probably send off a new front panel to Oshpark to have a new version made for testing soon.