# HG changeset patch # User Mychaela Falconia # Date 1648072557 0 # Node ID b99663e66660beb8a725f0140f9d9c61986917e2 # Parent f190b78c3b6ac99d089dbad3a45d234f4c485007 pirelli/chg-circuit: traced the current path to the battery diff -r f190b78c3b6a -r b99663e66660 pirelli/chg-circuit --- a/pirelli/chg-circuit Wed Mar 23 21:20:26 2022 +0000 +++ b/pirelli/chg-circuit Wed Mar 23 21:55:57 2022 +0000 @@ -71,3 +71,19 @@ on L7, microvia to L8 at (5514,741). On L8 the microvia lies in the polygon that connects the drain output of the P-MOSFET to the anode of the Schottky diode, matching TI's reference charging circuit. + +Now let's look for the main charging current path after the Schottky diode. On +L8 the cathode pad is a rectange, center at (5470,621), no visible microvia +hole. On L7 in this spot there is a polygon separate from GND pour, and in +this polygon 4 inner via holes are visible, arranged in a neat 2x2 pattern. +The upper left of these 4 vias is at (5514,538). On L1 there is a row of 4 +microvias from (5485,513) to (5542,511) - let's see if they fall into the +polygon on L2 that connects to the 4 inner vias for the charging current - they +do! The polygon on L1 with these 4 stitching microvias is where the charging +current comes to L1 - and lo and behold, on L1 we have a series resistor marked +"R200" whose other side goes directly to the positive rail on the physically +nearby battery connector! + +On L6 there is another connection to the 4-inner-vias charging current path, +possibly for the purpose of bringing this net to Iota VCCS - but the trace gets +lost in the grind-down damage.