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AS1326

Datasheet - A p p l i c a t i o n I n f o r m a t i o n

9 Application Information

Figure 19. Typical AS1326A Application Circuit

Setting the Output Voltages

For a fixed 3.3V output, connect pin FB to GND. To set adjustable output voltages between 2.5 and 5.0V, connect a

resistor voltage-divider to pin FB from pin OUT to GND (Figure 20).

Figure 20. Application Circuit using External Feedback Resistors

For the circuit shown in Figure 20, the input bias current into FB is <20nA, permitting large-value resistor-divider net-

works while maintaining accuracy. Place the resistor-divider network as close to the device as possible. Use a

≤ 270kΩ

Where:

9

POUT

10nF

33µF

AS1326A

10

ONN

6

CLK/SEL

1

ISET

2

REF

4

FB

3

GND

7

PGND

8

LX

3.3µH

+

5

OUT

100µF

+

330nF

800mA

9

POUT

10nF

33µF

AS1326A

10

ONN

6

CLK/SEL

1

ISET

2

REF

3

GND

7

PGND

8

LX

3.3µH

+

5

OUT

100µF

+

330nF

4

FB

(EQ 1)

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1

–

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