EUP3418 ds3418 ver1.3 apr. 2011 1 1.5mhz, 1a synchronous step-down converter with soft start description the EUP3418 is a constant frequency, current mode, pwm step-down converter. the device integrates a main switch and a synchronous rectifier for high efficiency. the 2.7v to 5.5v input voltage range ma kes the EUP3418 ideal for powering portable equipment that runs from a single cell lithium-ion (li+) batt ery or 3-cell nimh/ nicd batteries. the output voltage can be regulated as low as 0.6v. the EUP3418 supports up t o 1a load current and can also run at 100% duty cycle for low dropout applications, extending battery life in portable systems. switching frequency is internally set at 1.5mhz, allowing the use of small surface mount inductors a nd capacitors. the internal synchronous switch increas es efficiency while eliminates the need for an externa l schottky diode. typical application circuit features 25 a quiescent current at light load high efficiency up to 96% 1.5mhz constant switching frequency 1a available load current 2.7v to 5.5v input voltage range adjustable output voltage as low as 0.6v 100% duty cycle low dropout operation no schottky diode required short circuit and thermal protection excellent line and load transient response 1a shutdown current soft start function available in sot23-5, tsot23-5 package rohs compliant and 100% lead(pb)-free halogen-free applications cellular and smart phones portable media players/ mp3 players digital still and video cameras portable instruments wlan pc cards figure 1. adjustable output
|
