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AS1302

Datasheet - D e t a i l e d D e s c r i p t i o n

Switch Configuration

The AS1302 has nine built-in power switches in the shape of two coupled H-bridge topologies. The system features

1:2 and 2:3 operation modes as well as a 1:1 operation where the input is directly connected to the output.

In 2:3 operation mode two flying capacitors are placed in series and each capacitor is charged to the half of the input

voltage. In pumping phase the flying capacitors are placed in parallel. The bottom-plates of the parallel flying

5V, the regulation loop adapts the power transistor’s on-resistance to drop some voltage.

In 1:2 operation both flying capacitors are placed in parallel to the input voltage, and therefore charged to the input

voltage. During pumping phase the input voltage is connected to the bottom of the charged flying capacitors. The

5V the regulation loop limits the charge transfer to the output.

Figure 33. 2:3 Operating Mode

+2.9V to 5.15V

SW1

SW3

SW2

SW4

Charging Phase

+5V

+2.9V to 5.15V

SW1

SW3

SW2

SW4

Pumping Phase

+5V

Figure 34. 1:2 Operating Mode

+2.9V to 5.15V

SW1

SW3

SW2

SW4

+5V

Charging Phase

+2.9V to 5.15V

SW1

SW3

SW2

SW4

Pumping Phase

+5V