+
V
CC
-
Phase 2 – Vss transfer from C2 to C4.
Meanwhile C1 is charged to Vcc
+
C
+
+
+
V+
3
C
C
2
1
V
-
e
-
CC
e
Phases 1 and 3: Store/Double.
Double charge from C1 onto C2.
C2 is now charged to -2xVcc
-
e
-
+
C
4
Vss
+
C
+
+
V+
3
Patented 5,306,954
+
C
C
1
2
-
e
e
-
V-
+
V
CC
C
-
4
Phase 4 VDD
transfer from C2 to C3.
Meanwhile C1 is charged to Vcc
V
e
DD
+
e
+
+
C
+
+
V+
3
C
C
1
2
-
e
V-
+
C
4
Figure ꢀ. Charge pump phases
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