The LX1918 has a synchronous rectifier and all MOSFET switches and compensation components are built in. The synchronous rectification eliminates the need of an external Schottky diode and gives an efficiency level of >95% for a high step-down ratio and a low output voltage.
Input supply voltage ranges from 2.7V to 5.5V with a maximum output current of 1.5A. The LX1918 is a current mode PWM with optional PFM under light loads and can switch with a 1MHz free running internal oscillator or be synchronized with an external oscillator ranging from 500KHz to 1.25MHz.
Output voltage is programmable with two resistors and can be tightly regulated down to 0.6V. The MODE feature of the component can either maximize efficiency or reduce EMI depending on the needs of the application. High efficiency (MODE = GND) is obtained by allowing the LX1918 to enter a PFM mode with discontinuous inductor current. Low EMI (MODE=VCC) is obtained by only operating in PWM mode even at no load.
Featuring soft start, cycle-by-cycle switch current limit, hiccup short circuit current limiting and thermal shut down, the LX1918 comes in small 8 pin MLP package which is fully RoHS compliant.