Apollo Findings and Fixes

[Informaticore]

• ATTENTION: R47 came with a 10k resistor but should be 100k!!!!!!

General

• Change U8 Footprint from SOT23-6 to WSON (or exchange the component with the SOT version)
• Connect U8 VIN to actual VIN (missing label on the sheet)
• Replace the footprint used for the DMN3023L MOSFETs (Q3 & Q15) :
  Pin configuration : DGS (bad) -> GSD (good)
  https://www.diodes.com/assets/Datasheets/DMN3023L.pdf
• swap protection ic with version supporting auto enable ("A" versions)
• Remove SMBALERT wire between LTC4162-L chip (pin12) and the 2.54mm pitch 13pin connector (pin13). It will allow to use this pin for "one wire" RGB LED (RGB LED Out)
• Update SMBALERT LED (LED2) and resistor (R12) to DNP (Do Not Populate). It will allow the usage for DEBUG as an option and optimize the board Iq by default.
• Add a Solder Jumper (shorted by default) between Vbat+ and R1 (AP9101) to add the possibility to manually desactivate the battery protection feature when the battery has their own embedded chip. It will improve the board Iq.
• Rename some power signal on Schematic to improve readability.
• Increase QR Code Size (replace 5x5mm by 12x12mm)
• Add a Test Point for Battery Charger Output (Vin for DC-DC regulator and RTC)
• Flip JP3 (Top to bottom Layer)
• Flip JP1 Cell Number Selection (Top to bottom Layer)
• Add a new 0805 resistor in // to Rsns (R20) to improve resistor Max Power (0805 0.5W 130 mOhm x2 instead 0805 0.25W 68mOhm x1)

Board routing
LTC4162-L

• C3 4.7µF capacitor should be closer to the chip. (LTC internal regulator output pin 2)

Power Tracks width

• Increase Track width for Power lines (0.25mm is too small). Use at least 0.5mm for short tracks and more for longer tracks as possible to minimize power losses and keep a good voltage on DC-DC converters outputs. (Current can be >2A by track for DC-DC converters)
• Add more vias for Power Lines as possible. A good rule is to use one via for 500mA.

[MantaRayDeeJay]

Increase Track width for Power lines : Details

• Orange : +3.3V rail
• Red : +5V rail
• Yellow : Power rail (from USB power connector to the input of DC-DC converters)