Footprint's soldermask is missing?!

Layout Footprints
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I just remembered that i made a specialized footprint just for this component. (This footprint was already in production. But not in a reflow process. I hand soldered it.)
If you plan on reflow soldering this part you might need to split up the past layer for the exposed pad.

The footprint includes the thermal vias as recommended in the datasheet.
If you plan on using the balancing feature you might want to include them. (The component gets quite hot when balancing.)
TI_bq76PL536.kicad_mod (8.6 KB)

You can also take a look at my github project.
In the ibex project (108s20p battery) i use an stm32 to communicate with 25+24 such chips. There i have 15W resistors for balancing.
In the fennek project (12s1p battery) there are only 2 such chips. (More compact hardware with smaller balancing resistors. Two chips on one pcb.)
Maybe something is useful for you. Yes it is for a large battery.

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Looks complex and I don’t know where to start from when using these designs anyways you say I can’t use the default footprint for my PCB for re flow soldering?

Also do you have a recommended process for automating component assembly?
From what I understand the UI for kicad for that is a pain in the butt and you have you assign each foot print manufacturer link, part number and pos for assembly and that gets very time consuming when you have over 200 component of board…

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The paste stencil for the exposed pad will need work.
Normally the paste layer should be broken up into multiple smaller squares.
Example for such an application that gives details on this (yes it is for a qfn package but something similar will apply to your part as well)
http://www.ti.com/lit/an/sloa122/sloa122.pdf

A better more detailed application note (the interesting part is on page 5 and page 6)

It is a good practice to minimize voids within the exposed pad interconnection, so the design of the exposed pad stencil is crucial. The proposed stencil design enables out gassing of the solder paste during reflow and also regulates the finished solder thickness. Typically, the stencil apertures are reduced such that the solder paste coverage is 50% to 70% of the exposed pad area.

And as i said above you will need the thermal vias that are recommentd by TI if you plan to use the balancing feature. (The component gets quite hot.)
It already gets warm just from the internal voltage converters. (At least if you connect 6 cells per chip. Might be less of a problem if it needs to convert from lower supply voltages.)

Make sure you put the part to sleep when you do not need to monitor your battery. Otherwise it uses up a lot of energy. (Even a 60 Ah battery gets discharged within two or three month if you keep the chip active all the time. Yes i learned this the hard way.)

If you do so, don’t connect anything spi related to reg50 voltage supply because this supply gets turned off in sleep mode.

So connect hsel to ldoa (or an external voltage source) for devices connected via the daisy chain. (Yes i learned this the hard way as well. In this years version i could not enter sleep mode because i was unable to wake my parts up afterwards.)

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Aight thanks for the advice but what about automatic assemblies?

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I never used automatic assembly. I can not give advice for that. Maybe open a new topic where you specifically ask about that. (Most people simply read the title of a conversation and decide based on that if they can help.)

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A lot depends on who (or what) you plan to use for assembly, they usally have their own rules. Or you just send them the project and they sort it out.

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But unfortunately you cannot force automatic update of locked footprints?

It’s my experience, just want to verify (as it is inconvenient)

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Yup that is one use for locking footprints. (Example if you have a graphical symbol and don’t want it removed on net import.)

In other words: Locking a footprint tells kicad you do not want it changed by any tool in any way.

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Hmm

From my point of view I lock a footprint primarily to its location.

I still want the footprints to get refreshd from database without altering its position.

Unfortunately it’s no way you can choose force update of even locked footprint.

On large designs it impossible to keep in your head what components are locked or not.
And its not a visible attribute that locked footprints get a different color or something.

This makes it very dangerous/hard to ensure your footprints are in sync with your database.

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Also sometimes an old component that was removed from schematic will linger in pcb because it was locked down.

In my world it’s mandatory that pcb reflects the schematics.

No difference allowed after front annotation.

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If you open Scripting Console, something like this might work:

import pcbnew
z=map(lambda x: [p.SetSelected() for p in x.Pads()],filter(lambda x:x.IsLocked(),pcbnew.GetBoard().GetModules()))

This will select the pads of all locked modules, giving a visual indication of locked modules. You can replace SetSelected() with ClearSelected() to clear the selection.

You may have to switch canvases/views to see the selected items (F9 to F11 and back to F9).