AX3518 Datasheet | AXElite

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 ponents while keeping switching losses low. The internal slope pensation 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-8L 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-8L Pb-Free packages 1/12 AXElite Confidential Materials, do not copy or distribute without written consent . Rev.1.1 Aug.26, 2010  BLOCK DIAGRAM REF SVIN REF SLOPE P Isense AMP PVIN + Soft-Star FB + + Ip RESET PWM LOGIC - OVERLAP CONTROL Izero SGND Over-Temperature and Short - Circuit Protection Enable Logic  PIN ASSIGNMENT The packages of AX3518 are SOP-8L-EP and TDFN-8L; the pin assignment is given by: Name SVIN REF SGND FB Description Signal Supply Input...