GENERAL DESCRIPTION
That provides wide 4.5V to 18V input voltage range and 3A continuous load current capability. Internal compensation function. n FEATURES
l Wide 4.5V to 18V Operating Input Range l 80mΩ/30mΩ Low RDS(ON) internal Power MOSFETs l Proprietary Switching Loss Reduction Techn -ique l High Efficiency Synchronous Mode Operation l Fixed 500KHz Switching Frequency l External Programmable Soft Start l OCP and Hiccup l Thermal Shutdown l Output Adjustable from 0.8V l RoHS Compliant and Halogen Free n Application l Notebook Systems and I/O Power l Digital Set Top Boxes l LCD Display, TV l Networking, XDSL Modem n Typical Application VIN 4.5-18V C1 22uF 25V C3 1uF C4 22nF EN IN BST VCC SW AME5297 SS EN/SYNC FB GND R4 10Ω C4 0.1uF L1 4.7uH R1 40.2K R3 33K 3.3V 3A VOUT C2 47uF R2 13K Rev. A.05 1 AME AME5297 n Functional Block Diagram 3A, 18V, 500KHz Synchronous Step-Down DC/DC Converter IN VCC SS EN FB VCC Regulator M Oscillator Reference 1MEG 1pF 50pF 400k Error Amplifer Current Sense Amplifer RSEN VCC HS Driver Current Limit Comparator Comparator On Time Control Logic Control VCC LS Driver BST SW GND 2 Rev.
AME
