diff --git a/hw-rev-update-notes.txt b/hw-rev-update-notes.txt
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+* DO NOT USE U300; BAD PIN POLARITY USED! (also true for <=rev3.1!!)
+
+* rev2.0->rev2.1 rework needed:
+  * connect U400.6 to U400.7
+  * cut connection from U401.10 (to U500.1,R403; but cut close to U401)
+  * connect U400.5 to U401.10
+  * connect U400.7 to U500.1 ('Vdclo')
+  * if U400 not used: connect U400.5 to U400.7
+
+* to update rev2.0 -> rev3.x components:
+  * R1,2 -> R500,R405 (reuse component, new part assignment)
+  * new: R40{4,3,2}: 47k 0805
+  * new: R401: 47k OR 0Ohm; 0805
+  * new: R1,R2: 220k 0805
+  * new: C401: OPTIONAL 10uF 0603
+  * if >=rev3.2: D30{2,3,4,5} is now SOD-123F footprint, not SOD-323