diff --git a/src/main.cpp b/src/main.cpp
index 09b765e..2370936 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -142,7 +142,7 @@ void Panic(ErrorCode ec) {
 
 void RuntimeHWChecks() {
     mv::vcc.Step();
-    if (mv::vcc.CurrentVCC() > config::VCCADCThreshold) {
+    if (mv::vcc.CurrentBandgapVoltage() > config::VCCADCThreshold) {
         // stop all motors at once
         mm::motion.AbortPlannedMoves();
         // kill all TMC
diff --git a/src/modules/voltage.h b/src/modules/voltage.h
index c3cc065..f0ba9bd 100644
--- a/src/modules/voltage.h
+++ b/src/modules/voltage.h
@@ -14,7 +14,10 @@ namespace voltage {
 /// - AVCC=5V, you get VAL=225.06
 /// - AVCC=4.1V, you get VAL=274.46
 /// - AVCC=4V, you get VAL=281.35
-/// - any lower and the board will probably die sooner than being able to report anything
+///
+/// Any lower and the board will probably die sooner than being able to report anything.
+/// The TMC will die, but the atmega32u4 seems to be a bit more resilient.
+/// It's still out of spec anyway since the atmega32u4 is rated for 16MHz only at >4.5V.
 class VCC {
 public:
     inline constexpr VCC()
@@ -23,9 +26,9 @@ public:
     /// Reads the ADC, checks the value
     void Step();
 
-    /// @returns the current VCC voltage level, platform dependent.
+    /// @returns the current bandgap voltage level, platform dependent.
     /// @note see VCC measurement setup in config.h
-    uint16_t CurrentVCC() const { return vcc_val; }
+    uint16_t CurrentBandgapVoltage() const { return vcc_val; }
 
 private:
     uint16_t vcc_val;
diff --git a/src/registers.cpp b/src/registers.cpp
index f46d39d..b9351e3 100644
--- a/src/registers.cpp
+++ b/src/registers.cpp
@@ -164,7 +164,7 @@
 | 0x1eh 30 | uint16   | Set/Get Pulley iRun current| 0-31         | 14h 20      | 20->350mA: see TMC2130 current conversion| Read / Write | M707 A0x1e | M708 A0x1e Xn
 | 0x1fh 31 | uint16  |Set/Get Selector iRun current| 0-31         | 1fh 31      | 31->530mA: see TMC2130 current conversion| Read / Write | M707 A0x1f | M708 A0x1f Xn
 | 0x20h 32 | uint16   | Set/Get Idler iRun current | 0-31         | 1fh 31      | 31->530mA: see TMC2130 current conversion| Read / Write | M707 A0x20 | M708 A0x20 Xn
-| 0x21h 33 | uint16   | Current VCC voltage level  | 225-281 | | 225->5V, 281->4V, higher values mean lower voltage and the board would probably die sooner than reporting anything | Read only | M707 A0x21 | N/A
+| 0x21h 33 | uint16   | Current bandgap voltage level  | 225-281 | | 225->5V, 281->4V, higher values mean lower voltage and the board would probably die sooner than reporting anything | Read only | M707 A0x21 | N/A
 */
 
 struct RegisterFlags {
@@ -398,7 +398,7 @@ static const RegisterRec registers[] /*PROGMEM*/ = {
         1),
     // 0x21 Current VCC voltage level R
     RegisterRec(
-        []() -> uint16_t { return mv::vcc.CurrentVCC(); },
+        []() -> uint16_t { return mv::vcc.CurrentBandgapVoltage(); },
         2),
 };