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Axelite Confidential Materials, do not copy or distribute without written consent.

Rev.2.1 Oct.08, 2019

AX3102



APPLICATION CIRCUIT

R1

R2

VFB = 0.8V ; R2 suggest 0.8K ~ 6k

VOUT = VFB x (1 +

)

C2

470uF

C3

0.1uF

C4

470uF

1

2

L1

22uH

R1

30K

R2

5.6K

VIN+12V

ON/OFF

C1

1nF

VOUT = 5V/3A

R3

1.3K

R4

100K

D1

B340

C8

0.1uF

FB

1

EN

2

OCSET

3

VCC

4

SW

5

SW

6

VSS

7

VSS

8

AX3102

L1 recommend value (VIN=12V )

VOUT

1.8 V

2.5V

3.3V

5V

IOUT=3A

12uH

15uH

18uH

22uH



FUNCTION DESCRIPTIONS

PWM Control

The AX3102 consists of DC/DC converters that employ a pulse-width modulation

(PWM) system. In converters of the AX3102, the pulse width varies in a range from 0 to

100%, according to the load current. The ripple voltage produced by the switching can

easily be removed through a filter because the switching frequency remains constant.

Therefore, these converters provide a low-ripple power over broad ranges of input voltage

and load current.

RDS (ON) Current Limiting

The current limit threshold is setting by the external resistor (R3) connecting from VCC

supply to OCSET pin. The internal 130uA sink current crossing the resistor sets the voltage

at pin of OCSET. When the PWM voltage is less than the voltage at OCSET, an

over-current condition is triggered. Please refer to the formula for setting the current limit

value:

R

I

I

DS(ON)

OCSET

SW(MAX)

095

.

0

R3 





(Normally, The ISW(MAX) setting more than IOUT 1.0A ).