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

Rev.1.3 Nov.26, 2019

AX3518

1MHz, 3.2A Synchronous Step-Down

Converter



GENERAL DESCRIPTION

The AX3518 is a 1MHz constant frequency current mode PWM step-down converter. It

is ideal for portable equipment requiring very high current up to 3.2A from single-cell

Lithium-ion batteries while still achieving over 90% efficiency during peak load conditions.

The AX3518 also can run at 100% duty cycle for low dropout operation, extending battery

life in portable systems while light load operation provides very low output ripple for noise

sensitive applications. The AX3518 can supply up to 3.2A output load current from a 2.8V to

5.5V input voltage and the output voltage can be regulated as low as 0.8V. The high

switching frequency minimizes the size of external components while keeping switching

losses low. The internal slope compensation setting allows the device to operate with

smaller inductor values to optimize size and provide efficient operation. The AX3518 is

available in adjustable (0.8V to VIN) output voltage. The device is available in SOP-8L-EP

and TDFN-8 Pb-free packages.



FEATURES

- 2.8V to 5.5V Input Voltage Range

- Output Voltages from 0.8V to VIN

- High Efficiency: Up to 94%

- 1MHz Constant Frequency Operation

- With power saving mode

- Up to 3.2A Output Current

- No Schottky Diode Required

- Current Mode Operation for Excellent Line and Load Transient Response

- Current limit and thermal shutdown protection

- Short Circuit Protect (SCP)

- Build-in Soft Start function

- SOP-8L-EP and TDFN-8 Pb-Free packages

- RoHS and Halogen free compliance.