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6

C

2

+

-

V

CC

C

3

C

4

C

1

+

+

+

Phases 1 and 3: Store/Double.

Double charge from C1 onto C2.

C2 is now charged to -2xVcc

+

C

2

+

-

V

CC

C

3

C

4

C

1

+

+

+

+

C

2

+

-

V

CC

C

3

C

4

C

1

+

+

+

Phase 2 – Vss transfer from C2 to C4.

Meanwhile C1 is charged to Vcc

+

Vss

transfer from C2 to C3.

Meanwhile C1 is charged to Vcc

V

DD

V-

V+

V-

V+

V+

Patented 5,306,954

Figure . Charge pump phases