Fix MCP73831 subcircuit

- Add decoupling capacitor on Vbat
- Add more thermal support to layout (solid connection of ground to
  ground plane copper and addition of thermal vias)

Author: jonnew

Diff for: pcb/ephys-test-board.kicad_pcb

@@ -37,9 +37,9 @@
         "other_text_thickness": 0.15,
         "other_text_upright": false,
         "pads": {
-          "drill": 0.762,
-          "height": 1.524,
-          "width": 1.524
+          "drill": 0.0,
+          "height": 0.6,
+          "width": 1.325
         },
         "silk_line_width": 0.15,
         "silk_text_italic": false,
@@ -506,7 +506,10 @@
       "version": 3
     },
     "net_colors": null,
-    "netclass_assignments": null,
+    "netclass_assignments": {
+      "/MCU/D+": "l1-diff-90_jlc4161h",
+      "/MCU/D-": "l1-diff-90_jlc4161h"
+    },
     "netclass_patterns": [
       {
         "netclass": "l1-diff-90_jlc4161h",

Diff for: pcb/ephys-test-board.kicad_pro

@@ -6,7 +6,7 @@
 	(paper "A4")
 	(title_block
 		(title "Extracellular Electrophysiology Test Board")
-		(rev "A")
+		(rev "B")
 		(company "Open Ephys, Inc")
 		(comment 1 "Jonathan P. Newman")
 	)

Diff for: pcb/ephys-test-board.kicad_sch

@@ -6,7 +6,7 @@
 	(paper "A4")
 	(title_block
 		(title "Extracellular Electrophysiology Test Board")
-		(rev "A")
+		(rev "B")
 		(company "Open Ephys, Inc")
 		(comment 1 "Jonathan P. Newman")
 	)

Diff for: pcb/headstage-io.kicad_sch

@@ -0,0 +1,31 @@
+[html_defaults]
+dark_mode=0
+show_pads=1
+show_fabrication=0
+show_silkscreen=1
+redraw_on_drag=1
+highlight_pin1=none
+board_rotation=0
+offset_back_rotation=0
+checkboxes=Sourced,Placed
+bom_view=left-right
+layer_view=FB
+compression=1
+open_browser=1
+[general]
+bom_dest_dir=bom
+bom_name_format=ibom
+component_sort_order=C,R,L,D,U,Y,X,F,SW,A,~,HS,CNN,J,P,NT,MH
+component_blacklist=H*,TP*
+blacklist_virtual=1
+blacklist_empty_val=0
+include_tracks=0
+include_nets=0
+[fields]
+show_fields=Value,Footprint
+group_fields=Value,Footprint
+normalize_field_case=0
+board_variant_field=
+board_variant_whitelist=
+board_variant_blacklist=
+dnp_field=

Diff for: pcb/ibom.config.ini

@@ -6,7 +6,7 @@
 	(paper "A4")
 	(title_block
 		(title "Extracellular Electrophysiology Test Board")
-		(rev "A")
+		(rev "B")
 		(company "Open Ephys, Inc")
 		(comment 1 "Jonathan P. Newman")
 	)
@@ -12149,7 +12149,7 @@
 		(on_board yes)
 		(dnp no)
 		(uuid "d5710265-76a3-4a0d-a833-bc9656d867e7")
-		(property "Reference" "S1"
+		(property "Reference" "SW3"
 			(at 63.5 74.9299 90)
 			(effects
 				(font
@@ -12212,7 +12212,7 @@
 		(instances
 			(project "ephys-test-board"
 				(path "/ffaa6ffd-73fa-4da3-9ff1-78fa7369281f/72625ec8-68e6-44fb-ba42-4cf3e0d4f05e"
-					(reference "S1")
+					(reference "SW3")
 					(unit 1)
 				)
 			)

Diff for: pcb/mcu.kicad_sch

@@ -6,7 +6,7 @@
 	(paper "A4")
 	(title_block
 		(title "Extracellular Electrophysiology Test Board")
-		(rev "A")
+		(rev "B")
 		(company "Open Ephys, Inc")
 		(comment 1 "Jonathan P. Newman")
 	)
@@ -7955,7 +7955,7 @@
 				)
 			)
 		)
-		(property "Value" "SN74HCS595"
+		(property "Value" "SN74HCS595PWR"
 			(at 233.68 63.5 0)
 			(effects
 				(font

Diff for: pcb/signal-routing.kicad_sch

@@ -6,7 +6,7 @@
 	(paper "A4")
 	(title_block
 		(title "Extracellular Electrophysiology Test Board")
-		(rev "A")
+		(rev "B")
 		(company "Open Ephys, Inc")
 		(comment 1 "Jonathan P. Newman")
 	)
@@ -2283,7 +2283,7 @@
 				(justify left)
 			)
 		)
-		(property "Value" "MBR540"
+		(property "Value" "CDBW140-G"
 			(at 154.94 68.2625 90)
 			(effects
 				(font
@@ -3636,7 +3636,7 @@
 				(justify left)
 			)
 		)
-		(property "Value" "MBR540"
+		(property "Value" "CDBW140-G"
 			(at 154.94 75.8825 90)
 			(effects
 				(font